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Yang S, Wang X, Chu H, Liu W. Electrode-Supported Endohedral Metallofullerenes: Insights into the Confined Internal Dynamics. Inorg Chem 2024; 63:6836-6844. [PMID: 38567451 DOI: 10.1021/acs.inorgchem.4c00257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Endohedral metallofullerenes show great promise as molecular-scale memory units due to their robust architecture and protective capability for encapsulated atoms. However, the flat potential-energy surface within the cage often results in a severe disorder of encapsulated atoms. Here, we focused on prototypical systems involving Li@C60 on metallic surfaces, emphasizing the electrode's confinement effect on caged dynamics. We demonstrated that the varying interfacial stabilities induced by Li motion predominantly depend on the synergetic effect of van der Waals forces and covalent bonds rather than the previously assumed electrostatic interactions. We unveiled that the repulsion effect between encapsulated atom and the metal electrode primarily arises from the antibonding states between the metal states below the Fermi level and the degenerated frontier orbitals from HOMO-4 to HOMO. By manipulating orbital interactions, we observed an ordered arrangement of the encapsulated atom on Rec-Pt(111) at room temperature. Furthermore, our findings underscore the disruptive influence of electric fields on the stability of distinct Li positions, a phenomenon closely tied to the dipole moment induced by Li motion. This research provides a new perspective on the confined internal dynamics of endohedral metallofullerenes by manipulating cage-electrode interactions, contributing to precisely controlled molecular electronics.
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Affiliation(s)
- Sha Yang
- Nano and Heterogeneous Materials Center, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Xinyao Wang
- Nano and Heterogeneous Materials Center, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Han Chu
- Nano and Heterogeneous Materials Center, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Wei Liu
- Nano and Heterogeneous Materials Center, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
- State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
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2
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Bernbeck M, Orlova AP, Hilgar JD, Gembicky M, Ozerov M, Rinehart JD. Dipolar Coupling as a Mechanism for Fine Control of Magnetic States in ErCOT-Alkyl Molecular Magnets. J Am Chem Soc 2024; 146:7243-7256. [PMID: 38456803 PMCID: PMC10958522 DOI: 10.1021/jacs.3c10412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 02/13/2024] [Accepted: 02/14/2024] [Indexed: 03/09/2024]
Abstract
The design of molecular magnets has progressed greatly by taking advantage of the ability to impart successive perturbations and control vibronic transitions in 4fn systems through the careful manipulation of the crystal field. Herein, we control the orientation and rigidity of two dinuclear ErCOT-based molecular magnets: the inversion-symmetric bridged [ErCOT(μ-Me)(THF)]2 (2) and the nearly linear Li[(ErCOT)2(μ-Me)3] (3). The conserved anisotropy of the ErCOT synthetic unit facilitates the direction of the arrangement of its magnetic anisotropy for the purposes of generating controlled internal magnetic fields, improving control of the energetics and transition probabilities of the electronic angular momentum states with exchange biasing via dipolar coupling. This control is evidenced through the introduction of a second thermal barrier to relaxation operant at low temperatures that is twice as large in 3 as in 2. This barrier acts to suppress through-barrier relaxation by protecting the ground state from interacting with stray local fields while operating at an energy scale an order of magnitude smaller than the crystal field term. These properties are highlighted when contrasted against the mononuclear structure ErCOT(Bn)(THF)2 (1), in which quantum tunneling of the magnetization processes dominate, as demonstrated by magnetometry and ab initio computational methods. Furthermore, far-infrared magnetospectroscopy measurements reveal that the increased rigidity imparted by successive removal of solvent ligands when adding bridging methyl groups, along with the increased excited state purity, severely limits local spin-vibrational interactions that facilitate magnetic relaxation, manifesting as longer relaxation times in 3 relative to those in 2 as temperature is increased.
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Affiliation(s)
- Maximilian
G. Bernbeck
- Department
of Chemistry and Biochemistry, University
of California—San Diego, La Jolla, California 92093, United States
| | - Angelica P. Orlova
- Department
of Chemistry and Biochemistry, University
of California—San Diego, La Jolla, California 92093, United States
| | - Jeremy D. Hilgar
- Department
of Chemistry and Biochemistry, University
of California—San Diego, La Jolla, California 92093, United States
| | - Milan Gembicky
- Department
of Chemistry and Biochemistry, University
of California—San Diego, La Jolla, California 92093, United States
| | - Mykhaylo Ozerov
- National
High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - Jeffrey D. Rinehart
- Department
of Chemistry and Biochemistry, University
of California—San Diego, La Jolla, California 92093, United States
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3
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Hu Z, Yang S. Endohedral metallofullerene molecular nanomagnets. Chem Soc Rev 2024; 53:2863-2897. [PMID: 38324027 DOI: 10.1039/d3cs00991b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
Magnetic lanthanide (Ln) metal complexes exhibiting magnetic bistability can behave as molecular nanomagnets, also known as single-molecule magnets (SMMs), suitable for storing magnetic information at the molecular level, thus attracting extensive interest in the quest for high-density information storage and quantum information technologies. Upon encapsulating Ln ion(s) into fullerene cages, endohedral metallofullerenes (EMFs) have been proven as a promising and versatile platform to realize chemically robust SMMs, in which the magnetic properties are able to be readily tailored by altering the configurations of the encapsulated species and the host cages. In this review, we present critical discussions on the molecular structures and magnetic characterizations of EMF-SMMs, with the focus on their peculiar molecular and electronic structures and on the intriguing molecular magnetism arising from such structural uniqueness. In this context, different families of magnetic EMFs are summarized, including mononuclear EMF-SMMs wherein single-ion anisotropy is decisive, dinuclear clusterfullerenes whose magnetism is governed by intramolecular magnetic interaction, and radical-bridged dimetallic EMFs with high-spin ground states that arise from the strong ferromagnetic coupling. We then discuss how molecular assemblies of SMMs can be constructed, in a way that the original SMM behavior is either retained or altered in a controlled manner, thanks to the chemical robustness of EMFs. Finally, on the basis of understanding the structure-magnetic property correlation, we propose design strategies for high-performance EMF-SMMs by engineering ligand fields, electronic structures, magnetic interactions, and molecular vibrations that can couple to the spin states.
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Affiliation(s)
- Ziqi Hu
- Key Laboratory of Precision and Intelligent Chemistry, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Department of Materials Science and Engineering, Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei 230026, China.
| | - Shangfeng Yang
- Key Laboratory of Precision and Intelligent Chemistry, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Department of Materials Science and Engineering, Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei 230026, China.
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4
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Yang W, Velkos G, Rosenkranz M, Schiemenz S, Liu F, Popov AA. Nd─Nd Bond in I h and D 5h Cage Isomers of Nd 2 @C 80 Stabilized by Electrophilic CF 3 Addition. Adv Sci (Weinh) 2024; 11:e2305190. [PMID: 37946664 PMCID: PMC10767449 DOI: 10.1002/advs.202305190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 10/12/2023] [Indexed: 11/12/2023]
Abstract
Synthesis of molecular compounds with metal-metal bonds between 4f elements is recognized as one of the fascinating milestones in lanthanide metallochemistry. The main focus of such studies is on heavy lanthanides due to the interest in their magnetism, while bonding between light lanthanides remains unexplored. In this work, the Nd─Nd bonding in Nd-dimetallofullerenes as a case study of metal-metal bonding between early lanthanides is demonstrated. Combined experimental and computational study proves that pristine Nd2 @C80 has an open shell structure with a single electron occupying the Nd─Nd bonding orbital. Nd2 @C80 is stabilized by a one-electron reduction and further by the electrophilic CF3 addition to [Nd2 @C80 ]- . Single-crystal X-ray diffraction reveals the formation of two Nd2 @C80 (CF3 ) isomers with D5h -C80 and Ih -C80 carbon cages, both featuring a single-electron Nd─Nd bond with the length of 3.78-3.79 Å. The mutual influence of the exohedral CF3 group and endohedral metal dimer in determining the molecular structure of the adducts is analyzed. Unlike Tb or Dy analogs, which are strong single-molecule magnets with high blocking temperature of magnetization, the slow relaxation of magnetization in Nd2 @Ih -C80 (CF3 ) is detectable via out-of-phase magnetic susceptibility only below 3 K and in the presence of magnetic field.
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Affiliation(s)
- Wei Yang
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - Georgios Velkos
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - Marco Rosenkranz
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - Sandra Schiemenz
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - Fupin Liu
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - Alexey A. Popov
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
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5
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Yan Y, Abella L, Sun R, Fang YH, Roselló Y, Shen Y, Jin M, Rodríguez-Fortea A, de Graaf C, Meng Q, Yao YR, Echegoyen L, Wang BW, Gao S, Poblet JM, Chen N. Actinide-lanthanide single electron metal-metal bond formed in mixed-valence di-metallofullerenes. Nat Commun 2023; 14:6637. [PMID: 37863887 PMCID: PMC10589252 DOI: 10.1038/s41467-023-42165-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 10/02/2023] [Indexed: 10/22/2023] Open
Abstract
Understanding metal-metal bonding involving f-block elements has been a challenging goal in chemistry. Here we report a series of mixed-valence di-metallofullerenes, ThDy@C2n (2n = 72, 76, 78, and 80) and ThY@C2n (2n = 72 and 78), which feature single electron actinide-lanthanide metal-metal bonds, characterized by structural, spectroscopic and computational methods. Crystallographic characterization unambiguously confirmed that Th and Y or Dy are encapsulated inside variably sized fullerene carbon cages. The ESR study of ThY@D3h(5)-C78 shows a doublet as expected for an unpaired electron interacting with Y, and a SQUID magnetometric study of ThDy@D3h(5)-C78 reveals a high-spin ground state for the whole molecule. Theoretical studies further confirm the presence of a single-electron bonding interaction between Y or Dy and Th, due to a significant overlap between hybrid spd orbitals of the two metals.
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Affiliation(s)
- Yingjing Yan
- College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Laura Abella
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo 1, 43007, Tarragona, Spain
| | - Rong Sun
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Material Chemistry and Application, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
| | - Yu-Hui Fang
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Material Chemistry and Application, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
| | - Yannick Roselló
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo 1, 43007, Tarragona, Spain
| | - Yi Shen
- College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Meihe Jin
- College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Antonio Rodríguez-Fortea
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo 1, 43007, Tarragona, Spain
| | - Coen de Graaf
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo 1, 43007, Tarragona, Spain
- ICREA, Pg. Lluís Companys 23, 08010, Barcelona, Spain
| | - Qingyu Meng
- College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Yang-Rong Yao
- College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu, 215123, P. R. China.
- Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, 230026, P. R. China.
| | - Luis Echegoyen
- Department of Chemistry, University of Texas at El Paso, 500 W University Avenue, El Paso, TX, 79968, USA
| | - Bing-Wu Wang
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Material Chemistry and Application, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China.
| | - Song Gao
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Material Chemistry and Application, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
| | - Josep M Poblet
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo 1, 43007, Tarragona, Spain.
| | - Ning Chen
- College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, Jiangsu, 215123, P. R. China.
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6
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Swain A, Sharma T, Rajaraman G. Strategies to quench quantum tunneling of magnetization in lanthanide single molecule magnets. Chem Commun (Camb) 2023; 59:3206-3228. [PMID: 36789911 DOI: 10.1039/d2cc06041h] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Enhancing blocking temperature (TB) is one of the holy grails in Single Molecule Magnets(SMMs), as any future potential application in this class of molecules is directly correlated to this parameter. Among many factors contributing to a reduction of TB value, Quantum Tunnelling of Magnetisation (QTM), a phenomenon that is a curse or a blessing based on the application sought after, tops the list. Theoretical tools based on density functional and ab initio CASSCF/RASSI-SO methods have played a prominent role in estimating various spin Hamiltonian parameters and establishing the mechanism of magnetization relaxation in this class of molecules. Particularly, various strategies to quench QTM effects go hand-in-hand with experiments, and different methods proposed to quell QTM effects are scattered in the literature. In this perspective, we have explored various approaches that are proposed in the literature to quench QTM effects, and these include the role of (i) local symmetry of lanthanides, (ii) super-exchange interaction in {3d-4f} complexes, (iii) direct-exchange interaction in {radical-4f} and metal-metal bonded complexes to suppress the QTM, (iv) utilizing external stimuli such as an electric field or pressure to modulate the QTM and (v) avoiding QTM effects by stabilising toroidal states in 4f and {3d-4f} clusters. We believe the strategies summarized here will help to design new-generation SMMs.
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Affiliation(s)
- Abinash Swain
- Department of Chemistry, IIT Bombay, Powai, Mumbai - 400076, India.
| | - Tanu Sharma
- Department of Chemistry, IIT Bombay, Powai, Mumbai - 400076, India.
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7
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Koutsouflakis E, Krylov D, Bachellier N, Sostina D, Dubrovin V, Liu F, Spree L, Velkos G, Schimmel S, Wang Y, Büchner B, Westerström R, Bulbucan C, Kirkpatrick K, Muntwiler M, Dreiser J, Greber T, Avdoshenko SM, Dorn H, Popov AA. Metamagnetic transition and a loss of magnetic hysteresis caused by electron trapping in monolayers of single-molecule magnet Tb 2@C 79N. Nanoscale 2022; 14:9877-9892. [PMID: 35781298 DOI: 10.1039/d1nr08475e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Realization of stable spin states in surface-supported magnetic molecules is crucial for their applications in molecular spintronics, memory storage or quantum information processing. In this work, we studied the surface magnetism of dimetallo-azafullerene Tb2@C79N, showing a broad magnetic hysteresis in a bulk form. Surprisingly, monolayers of Tb2@C79N exhibited a completely different behavior, with the prevalence of a ground state with antiferromagnetic coupling at low magnetic field and a metamagnetic transition in the magnetic field of 2.5-4 T. Monolayers of Tb2@C79N were deposited onto Cu(111) and Au(111) by evaporation in ultra-high vacuum conditions, and their topography and electronic structure were characterized by scanning tunneling microscopy and spectroscopy (STM/STS). X-ray photoelectron spectroscopy (XPS), in combination with DFT studies, revealed that the nitrogen atom of the azafullerene cage tends to avoid metallic surfaces. Magnetic properties of the (sub)monolayers were then studied by X-ray magnetic circular dichroism (XMCD) at the Tb-M4,5 absorption edge. While in bulk powder samples Tb2@C79N behaves as a single-molecule magnet with ferromagnetically coupled magnetic moments and blocking of magnetization at 28 K, its monolayers exhibited a different ground state with antiferromagnetic coupling of Tb magnetic moments. To understand if this unexpected behavior is caused by a strong hybridization of fullerenes with metallic substrates, XMCD measurements were also performed for Tb2@C79N adsorbed on h-BN|Rh(111) and MgO|Ag(100). The co-existence of two forms of Tb2@C79N was found on these substrates as well, but magnetization curves showed narrow magnetic hysteresis detectable up to 25 K. The non-magnetic state of Tb2@C79N in monolayers is assigned to anionic Tb2@C79N- species with doubly-occupied Tb-Tb bonding orbital and antiferromagnetic coupling of the Tb moments. A charge transfer from the substrate or trapping of secondary electrons are discussed as a plausible origin of these species.
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Affiliation(s)
- Emmanouil Koutsouflakis
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany.
| | - Denis Krylov
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany.
| | - Nicolas Bachellier
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Daria Sostina
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Vasilii Dubrovin
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany.
| | - Fupin Liu
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany.
| | - Lukas Spree
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany.
| | - Georgios Velkos
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany.
| | - Sebastian Schimmel
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany.
| | - Yaofeng Wang
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany.
| | - Bernd Büchner
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany.
| | - Rasmus Westerström
- The Division of Synchrotron Radiation Research, Lund University, SE-22100 Lund, Sweden
- NanoLund, Lund University, Box 118, 22100 Lund, Sweden
| | - Claudiu Bulbucan
- The Division of Synchrotron Radiation Research, Lund University, SE-22100 Lund, Sweden
- NanoLund, Lund University, Box 118, 22100 Lund, Sweden
| | - Kyle Kirkpatrick
- Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
| | - Matthias Muntwiler
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Jan Dreiser
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Thomas Greber
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
- Physik-Institut der Universität Zürich, Winterthurerstr. 190, CH-8057 Zürich, Switzerland
| | - Stas M Avdoshenko
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany.
| | - Harry Dorn
- Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
| | - Alexey A Popov
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany.
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8
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Nguyen GT, Ungur L. The Role of Radical Bridges in Polynuclear Single‐Molecule Magnets. Chemistry 2022; 28:e202200227. [DOI: 10.1002/chem.202200227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Indexed: 11/08/2022]
Affiliation(s)
- Giang Truong Nguyen
- Department of Chemistry Faculty of Science National University of Singapore Block S8 Level 3, 3 Science Drive 3 Singapore Singapore 117543
| | - Liviu Ungur
- Department of Chemistry Faculty of Science National University of Singapore Block S8 Level 3, 3 Science Drive 3 Singapore Singapore 117543
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9
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Dey S, Rajaraman G. Attaining record-high magnetic exchange, magnetic anisotropy and blocking barriers in dilanthanofullerenes. Chem Sci 2021; 12:14207-14216. [PMID: 34760206 PMCID: PMC8565386 DOI: 10.1039/d1sc03925c] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 10/06/2021] [Indexed: 11/29/2022] Open
Abstract
While the blocking barrier (U eff) and blocking temperature (T B) for "Dysprocenium" SIMs have been increased beyond liquid N2 temperature, device fabrication of these molecules remains a challenge as low-coordinate Ln3+ complexes are very unstable. Encapsulating the lanthanide ion inside a cage such as a fullerene (called endohedral metallofullerene or EMF) opens up a new avenue leading to several Ln@EMF SMMs. The ab initio CASSCF calculations play a pivotal role in identifying target metal ions and suitable cages in this area. Encouraged by our earlier prediction on Ln2@C79N, which was verified by experiments, here we have undertaken a search to enhance the exchange coupling in this class of molecules beyond the highest reported value. Using DFT and ab initio calculations, we have studied a series of Gd2@C2n (30 ≤ 2n ≤ 80), where an antiferromagnetic J Gd⋯Gd of -43 cm-1 was found for a stable Gd2@C38-D 3h cage. This extremely large and exceptionally rare 4f⋯4f interaction results from a direct overlap of 4f orbitals due to the confinement effect. In larger cages such as Gd2@C60 and Gd2@C80, the formation of two centre-one-electron (2c-1e-) Gd-Gd bonds is perceived. This results in a radical formation in the fullerene cage leading to its instability. To avoid this, we have studied heterofullerenes where one of the carbon atoms is replaced by a nitrogen atom. Specifically, we have studied Ln2@C59N and Ln2@C79N, where strong delocalisation of the electron yields a mixed valence-like behaviour. This suggests a double-exchange (B) is operational, and CASSCF calculations yield a B value of 434.8 cm-1 and resultant J Gd-rad of 869.5 cm-1 for the Gd2@C59N complex. These parameters are found to be two times larger than the world-record J reported for Gd2@C79N. Further ab initio calculations reveal an unprecedented U cal of 1183 and 1501 cm-1 for Dy2@C59N and Tb2@C59N, respectively. Thus, this study offers strong exchange coupling as criteria for new generation SMMs as the existing idea of enhancing the blocking barrier via crystal field modulation has reached its saturation point.
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Affiliation(s)
- Sourav Dey
- Department of Chemistry, Indian Institute of Technology Bombay Powai Mumbai 400076 India
| | - Gopalan Rajaraman
- Department of Chemistry, Indian Institute of Technology Bombay Powai Mumbai 400076 India
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10
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Sharma T, Singh MK, Gupta R, Khatua M, Rajaraman G. In silico design to enhance the barrier height for magnetization reversal in Dy(iii) sandwich complexes by stitching them under the umbrella of corannulene. Chem Sci 2021; 12:11506-11514. [PMID: 34667554 PMCID: PMC8447237 DOI: 10.1039/d1sc03160k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 07/17/2021] [Indexed: 11/21/2022] Open
Abstract
Lanthanide based single molecular magnets (SMMs), particularly dysprocenium based SIMs, are well known for their high energy barrier for spin reversal (U eff) and blocking temperatures (T B). Enhancing these two parameters and at the same time obtaining ambient stability is key to realising end-user applications such as compact storage or as qubits in quantum computing. In this work, by employing an array of theoretical tools (DFT, ab initio CASSCF and molecular dynamics), we have modelled six complexes [(η5-corannulene)Dy(Cp)] (1), [(η5-corannulene)Dy(C6H6)] (2), [(η6-corannulene)Dy(Cp)] (3), [(η6-corannulene)Dy(C6H6)] (4), [(exo-η5-corannulene)Dy(endo-η5-corannulene)] (5), and [(endo-η5-corannulene)Dy(endo-η5-corannulene)] (6) containing corannulene as a capping ligand to stabilise Dy(iii) half-sandwich complexes. Our calculations predict a strong axiality exerted by the Dy-C interactions in all complexes. Ab initio calculations predict a very large barrier height for all six molecules in the order 1 (919 cm-1) ≈ 3 (913 cm-1) > 2 (847 cm-1) > 4 (608 cm-1) ≈ 5 (603 cm-1) ≈ 6 (599 cm-1), suggesting larger barrier heights for Cp ring systems, followed by six-membered arene systems and then corannulene. DFT based molecular dynamics calculations were performed on complexes 3, 5 and 6. For complexes 3 and 5, the geometries that are dynamically accessible are far fewer. The range of U eff computed for molecular dynamics snapshots is high, indicating a possibility of translating the large U eff obtained into attractive blocking temperatures in these complexes, but the converse is found for 6. Furthermore, an in-depth C-H bond vibrational analysis performed on complex 3 suggests that the vibration responsible for reducing the blocking temperature in dysprocenium SIMs is absent here as the C-H bonds are stronger and corannulene steric strain prevents the C(Cp)-Dy-C(Cor) bending. As [(η6-corannulene)TM(X)]+ (TM = Ru, Zr, Os, Rh, Ir and X = C5Me5, C6Me6) are known, the predictions made here have a higher prospect of yielding stability under ambient conditions, a very large U eff value and a high blocking temperature - a life-giving combination to new generation SMMs.
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Affiliation(s)
- Tanu Sharma
- Department of Chemistry, Indian Institute of Technology Bombay Mumbai-400076 India +91-22-2576-7187
| | - Mukesh Kumar Singh
- Department of Chemistry, Indian Institute of Technology Bombay Mumbai-400076 India +91-22-2576-7187
| | - Radhika Gupta
- Department of Chemistry, Indian Institute of Technology Bombay Mumbai-400076 India +91-22-2576-7187
| | - Munmun Khatua
- Department of Chemistry, Indian Institute of Technology Bombay Mumbai-400076 India +91-22-2576-7187
| | - Gopalan Rajaraman
- Department of Chemistry, Indian Institute of Technology Bombay Mumbai-400076 India +91-22-2576-7187
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11
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Kanetomo T, Naoi Y, Enomoto M. Gadolinium‐Triradical Complex with Ground
S
= 10 State: Synthesis, Structural Characterization and Magnetic Studies. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202001113] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Takuya Kanetomo
- Department of Chemistry, Faculty of Science Division 1 Tokyo University of Science 1–3 Kagurazaka, Shinjuku-ku Tokyo 162-8601 Japan
| | - Yuya Naoi
- Department of Chemistry, Faculty of Science Division 1 Tokyo University of Science 1–3 Kagurazaka, Shinjuku-ku Tokyo 162-8601 Japan
| | - Masaya Enomoto
- Department of Chemistry, Faculty of Science Division 1 Tokyo University of Science 1–3 Kagurazaka, Shinjuku-ku Tokyo 162-8601 Japan
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12
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López-Moreno A, del Carmen Giménez-López M. Metallic-based magnetic switches under confinement. Advances in Organometallic Chemistry 2021. [DOI: 10.1016/bs.adomc.2021.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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13
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Iwami H, Xing J, Nakanishi R, Horii Y, Katoh K, Breedlove BK, Kawachi K, Kasama Y, Kwon E, Yamashita M. Cocrystals of Li + encapsulated fullerenes and Tb(iii) double-decker single molecule magnet in a quasi-kagome lattice. Chem Commun (Camb) 2020; 56:12785-12788. [PMID: 32966411 DOI: 10.1039/d0cc04349d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cocrystallization of a lithium ion encapsulated fullerene Li+@C60 with a terbium(iii) phthalocyaninato porphyrinato double-decker single-molecule magnet [Tb(Pc)(OEP)] is reported. The cocrystal, containing PF6- as a counter anion, packs in a quasi-kagome lattice, which leads to intermolecular ferromagnetic interactions as well as the modulation of the single-molecule magnet (SMM) properties.
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Affiliation(s)
- Hikaru Iwami
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3, Aramaki-Aza-Aoba, Aoba-ku, Sendai 980-8578, Japan
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14
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Mondal A, Roy S, Konar S. Remarkable Energy Barrier for Magnetization Reversal in 3D and 2D Dysprosium-Chloranilate-Based Coordination Polymers. Chemistry 2020; 26:8774-8783. [PMID: 32315101 DOI: 10.1002/chem.202000438] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 04/16/2020] [Indexed: 12/26/2022]
Abstract
Herein, two coordination polymers (CPs) [{Dy(Cl2 An)1.5 (CH3 OH)}⋅4.5 H2 O]n (1) and [Dy(Cl2 An)1.5 (DMF)2 ]n (2), in which Cl2 An is chloranilate (2,5-dihydroxy-1,4-benzoquinone dianion), exhibiting field-induced single-molecule magnet behavior with moderate barrier of magnetization reversal are reported. Detailed structural and topological analysis disclosed that 1 has a 3D network, whereas 2 has a 2D layered-type structure. In both CPs, magnetic measurements showed weak antiferromagnetic exchange interaction between the dysprosium centers and field-induced slow magnetic relaxation with barriers of 175(9)K and 145(7)K for 1 and 2, respectively. Notably, the energy barriers of magnetization reversal of 1 and 2 are remarkable for metal-chloranilate-based 3D (1) and 2D (2) CPs. The temperature and field dependence of relaxation time indicate the presence of multiple relaxation pathways, such as direct, quantum tunneling of magnetization, Raman, and Orbach processes, in both CPs. Ab initio theoretical calculations reinforced the experimentally observed higher energy barrier in 1 as compared with 2 due to the presence of large transverse anisotropy in the ground state in the latter. The average transition magnetic moment between the computed low-lying spin-orbit states also rationalized the relaxation as Orbach and Raman processes through the first excited state. BS-DFT calculations were carried out for both CPs to provide more insight into the exchange interaction.
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Affiliation(s)
- Arpan Mondal
- Department of Chemistry, Indian Institute of Science Education and Research, Bhopal, Bhopal By-pass Road, Bhauri, Bhopal, 462066, Madhya Pradesh, India
| | - Subhadip Roy
- Department of Chemistry, The ICFAI University Tripura, Kamalghat, Mohanpur, Agartala, Tripura, 799210, India
| | - Sanjit Konar
- Department of Chemistry, Indian Institute of Science Education and Research, Bhopal, Bhopal By-pass Road, Bhauri, Bhopal, 462066, Madhya Pradesh, India
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15
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Wang Y, Xiong J, Su J, Hu Z, Ma F, Sun R, Tan X, Sun HL, Wang BW, Shi Z, Gao S. Dy 2@C 79N: a new member of dimetalloazafullerenes with strong single molecular magnetism. Nanoscale 2020; 12:11130-11135. [PMID: 32400841 DOI: 10.1039/d0nr02519d] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Enhancing the exchange interaction between magnetic ions is a long-term target in molecular magnetism. Endohedral metallofullerenes (EMFs) provide a possibility for achieving such a goal by imprisoning multiple magnetic centers inside the confined inner space of a fullerene cage. Here, we report a new member of dimetallic azafullerene Dy2@C79N via crystallographic determination for the first time. Magnetic studies indicate that the strong ferromagnetic coupling between lanthanide ions and unpaired electrons enables Dy2@C79N to be a favorable SMM with large energy barrier of U = 669 K and observable hysteresis loops below 24 K.
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Affiliation(s)
- Yuanyuan Wang
- Beijing National Laboratory for Molecular Science, State Key Lab of Rare Earth, Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peiking University, Beijing, 100871, P. R. China.
| | - Jin Xiong
- Beijing National Laboratory for Molecular Science, State Key Lab of Rare Earth, Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peiking University, Beijing, 100871, P. R. China.
| | - Jie Su
- Beijing National Laboratory for Molecular Science, State Key Lab of Rare Earth, Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peiking University, Beijing, 100871, P. R. China.
| | - Ziqi Hu
- Beijing National Laboratory for Molecular Science, State Key Lab of Rare Earth, Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peiking University, Beijing, 100871, P. R. China.
| | - Fang Ma
- Department of Chemistry and Beijing Key Laboratory of Energy Conversion and Storage Materials, Beijing Normal University, Beijing 100875, P. R. China.
| | - Rong Sun
- Beijing National Laboratory for Molecular Science, State Key Lab of Rare Earth, Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peiking University, Beijing, 100871, P. R. China.
| | - Xueyou Tan
- Beijing National Laboratory for Molecular Science, State Key Lab of Rare Earth, Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peiking University, Beijing, 100871, P. R. China.
| | - Hao-Ling Sun
- Department of Chemistry and Beijing Key Laboratory of Energy Conversion and Storage Materials, Beijing Normal University, Beijing 100875, P. R. China.
| | - Bing-Wu Wang
- Beijing National Laboratory for Molecular Science, State Key Lab of Rare Earth, Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peiking University, Beijing, 100871, P. R. China.
| | - Zujin Shi
- Beijing National Laboratory for Molecular Science, State Key Lab of Rare Earth, Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peiking University, Beijing, 100871, P. R. China.
| | - Song Gao
- Beijing National Laboratory for Molecular Science, State Key Lab of Rare Earth, Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peiking University, Beijing, 100871, P. R. China.
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16
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Izuogu DC, Yoshida T, Cosquer G, Asegbeloyin JN, Zhang H, Thom AJW, Yamashita M. Periodicity of Single‐Molecule Magnet Behaviour of Heterotetranuclear Lanthanide Complexes across the Lanthanide Series: A Compendium. Chemistry 2020; 26:6036-6049. [DOI: 10.1002/chem.202000161] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 02/04/2020] [Indexed: 11/06/2022]
Affiliation(s)
- David Chukwuma Izuogu
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
- Department of ChemistryGraduate School of ScienceTohoku University 6-3 Aza-Aoba, Aramaki Sendai 980-8578 Japan
- Department of Pure and Industrial ChemistryUniversity of Nigeria, Nsukka 410001 Enugu State Nigeria
| | - Takefumi Yoshida
- Department of ChemistryGraduate School of ScienceTohoku University 6-3 Aza-Aoba, Aramaki Sendai 980-8578 Japan
- WPI-Advanced Institute for Materials Research (AIMR)Tohoku University 2-1-1 Katahira Sendai 980-8577 Japan
| | - Goulven Cosquer
- Department of ChemistryGraduate School of ScienceHiroshima University 1-3-1 Kagamiyama Higashihiroshima 739-8526 Japan
| | - Jonnie N. Asegbeloyin
- Department of Pure and Industrial ChemistryUniversity of Nigeria, Nsukka 410001 Enugu State Nigeria
| | - Haitao Zhang
- Department of ChemistryGraduate School of ScienceTohoku University 6-3 Aza-Aoba, Aramaki Sendai 980-8578 Japan
| | - Alex J. W. Thom
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Masahiro Yamashita
- Department of ChemistryGraduate School of ScienceTohoku University 6-3 Aza-Aoba, Aramaki Sendai 980-8578 Japan
- WPI-Advanced Institute for Materials Research (AIMR)Tohoku University 2-1-1 Katahira Sendai 980-8577 Japan
- School of Materials Science and EngineeringNankai University Tianjin 300350 P.R. China
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17
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Krylov DS, Schimmel S, Dubrovin V, Liu F, Nguyen TTN, Spree L, Chen C, Velkos G, Bulbucan C, Westerström R, Studniarek M, Dreiser J, Hess C, Büchner B, Avdoshenko SM, Popov AA. Substrate‐Independent Magnetic Bistability in Monolayers of the Single‐Molecule Magnet Dy
2
ScN@C
80
on Metals and Insulators. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201913955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Denis S. Krylov
- Leibniz Institute for Solid State and Materials Research Helmholtzstraße 20 01069 Dresden Germany
- Center for Quantum Nanoscience Institute for Basic Science (IBS) Seoul Republic of Korea
| | - Sebastian Schimmel
- Leibniz Institute for Solid State and Materials Research Helmholtzstraße 20 01069 Dresden Germany
| | - Vasilii Dubrovin
- Leibniz Institute for Solid State and Materials Research Helmholtzstraße 20 01069 Dresden Germany
| | - Fupin Liu
- Leibniz Institute for Solid State and Materials Research Helmholtzstraße 20 01069 Dresden Germany
| | - T. T. Nhung Nguyen
- Leibniz Institute for Solid State and Materials Research Helmholtzstraße 20 01069 Dresden Germany
| | - Lukas Spree
- Leibniz Institute for Solid State and Materials Research Helmholtzstraße 20 01069 Dresden Germany
| | - Chia‐Hsiang Chen
- Leibniz Institute for Solid State and Materials Research Helmholtzstraße 20 01069 Dresden Germany
- Department of Medicinal and Applied Chemistry Kaohsiung Medical University Kaohsiung 807 Taiwan
| | - Georgios Velkos
- Leibniz Institute for Solid State and Materials Research Helmholtzstraße 20 01069 Dresden Germany
| | - Claudiu Bulbucan
- The division of synchrotron radiation research Lund University 22100 Lund Sweden
| | - Rasmus Westerström
- The division of synchrotron radiation research Lund University 22100 Lund Sweden
| | - Michał Studniarek
- Swiss Light Source Paul Scherrer Institute 5232 Villigen PSI Switzerland
| | - Jan Dreiser
- Swiss Light Source Paul Scherrer Institute 5232 Villigen PSI Switzerland
| | - Christian Hess
- Leibniz Institute for Solid State and Materials Research Helmholtzstraße 20 01069 Dresden Germany
| | - Bernd Büchner
- Leibniz Institute for Solid State and Materials Research Helmholtzstraße 20 01069 Dresden Germany
| | - Stanislav M. Avdoshenko
- Leibniz Institute for Solid State and Materials Research Helmholtzstraße 20 01069 Dresden Germany
| | - Alexey A. Popov
- Leibniz Institute for Solid State and Materials Research Helmholtzstraße 20 01069 Dresden Germany
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18
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Krylov DS, Schimmel S, Dubrovin V, Liu F, Nguyen TTN, Spree L, Chen C, Velkos G, Bulbucan C, Westerström R, Studniarek M, Dreiser J, Hess C, Büchner B, Avdoshenko SM, Popov AA. Substrate-Independent Magnetic Bistability in Monolayers of the Single-Molecule Magnet Dy 2 ScN@C 80 on Metals and Insulators. Angew Chem Int Ed Engl 2020; 59:5756-5764. [PMID: 31860759 PMCID: PMC7155138 DOI: 10.1002/anie.201913955] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 12/11/2019] [Indexed: 01/08/2023]
Abstract
Magnetic hysteresis is demonstrated for monolayers of the single-molecule magnet (SMM) Dy2 ScN@C80 deposited on Au(111), Ag(100), and MgO|Ag(100) surfaces by vacuum sublimation. The topography and electronic structure of Dy2 ScN@C80 adsorbed on Au(111) were studied by STM. X-ray magnetic CD studies show that the Dy2 ScN@C80 monolayers exhibit similarly broad magnetic hysteresis independent on the substrate used, but the orientation of the Dy2 ScN cluster depends strongly on the surface. DFT calculations show that the extent of the electronic interaction of the fullerene molecules with the surface is increasing dramatically from MgO to Au(111) and Ag(100). However, the charge redistribution at the fullerene-surface interface is fully absorbed by the carbon cage, leaving the state of the endohedral cluster intact. This Faraday cage effect of the fullerene preserves the magnetic bistability of fullerene-SMMs on conducting substrates and facilitates their application in molecular spintronics.
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Affiliation(s)
- Denis S. Krylov
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
- Center for Quantum NanoscienceInstitute for Basic Science (IBS)SeoulRepublic of Korea
| | - Sebastian Schimmel
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - Vasilii Dubrovin
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - Fupin Liu
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - T. T. Nhung Nguyen
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - Lukas Spree
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - Chia‐Hsiang Chen
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
- Department of Medicinal and Applied ChemistryKaohsiung Medical UniversityKaohsiung807Taiwan
| | - Georgios Velkos
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - Claudiu Bulbucan
- The division of synchrotron radiation researchLund University22100LundSweden
| | - Rasmus Westerström
- The division of synchrotron radiation researchLund University22100LundSweden
| | - Michał Studniarek
- Swiss Light SourcePaul Scherrer Institute5232Villigen PSISwitzerland
| | - Jan Dreiser
- Swiss Light SourcePaul Scherrer Institute5232Villigen PSISwitzerland
| | - Christian Hess
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - Bernd Büchner
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - Stanislav M. Avdoshenko
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
| | - Alexey A. Popov
- Leibniz Institute for Solid State and Materials ResearchHelmholtzstraße 2001069DresdenGermany
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19
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Swain A, Sarkar A, Rajaraman G. Role of Ab Initio Calculations in the Design and Development of Organometallic Lanthanide-Based Single-Molecule Magnets. Chem Asian J 2019; 14:4056-4073. [PMID: 31557389 DOI: 10.1002/asia.201900828] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 09/23/2019] [Indexed: 11/11/2022]
Abstract
Single-molecule magnets based on lanthanides are very attractive due to their potential applications proposed in the area of microelectronic devices. Very recent advances in this area are due to the blend of conventional lanthanide chemistry with organometallic ligands, and several breakthrough achievements are attained with this combination. Ab initio methods based on multi-reference CASSCF calculations are playing a vital role in the design and development of such molecules. In this minireview, we aim to appraise various contributions in the area of organometallic lanthanide complexes (those containing lanthanide-carbon bonds) and describe how these robust wavefunction-based methods have played a constructive role not only in rationalizing the observed magnetic properties but also proven to be a potential predictive tool with some selected examples.
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Affiliation(s)
- Abinash Swain
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Arup Sarkar
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Gopalan Rajaraman
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
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20
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Konarev DV, Popov AA, Zorina LV, Khasanov SS, Lyubovskaya RN. Molecular Structure and Magnetic and Optical Properties of Endometallonitridofullerene Sc 3 N@I h -C 80 in Neutral, Radical Anion, and Dimeric Anionic Forms. Chemistry 2019; 25:14858-14869. [PMID: 31523861 DOI: 10.1002/chem.201902782] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 09/08/2019] [Indexed: 11/07/2022]
Abstract
A series of compounds with Sc3 N@Ih -C80 in the neutral, monomeric, and dimeric anion states have been prepared in the crystalline form and their molecular structures and optical and magnetic properties have been studied. The neutral Sc3 N@Ih -C80 ⋅3 C6 H4 Cl2 (1) and (Sc3 N@Ih -C80 )3 (TPC)2 ⋅5 C6 H4 Cl2 (2, TPC=triptycene) compounds both crystallized in a high-symmetry trigonal structure. The reduction of Sc3 N@Ih -C80 to the radical anion resulted in dimerization to form diamagnetic singly bonded (Sc3 N@Ih -C80 - )2 dimers. In contrast to {[2.2.2]cryptand(Na+ )}2 (Sc3 N@Ih -C80 - )2 ⋅2.5 C6 H4 Cl2 (3) with strongly disordered components, we synthesized new dimeric phases {[2.2.2]cryptand- (K+ )}2 (Sc3 N@Ih -C80 - )2 ⋅2 C6 H4 Cl2 (4) and {[2.2.2]cryptand- (Cs+ )}2 (Sc3 N@Ih -C80 - )2 ⋅2 C6 H4 Cl2 (5) in which only one major dimer orientation was found. The thermal stability of the (Sc3 N@Ih -C80 - )2 dimers was studied by EPR analysis of 3 to show their dissociation in the 400-460 K range producing monomeric Sc3 N@Ih -C80 .- radical anions. This species shows an EPR signal with a hyperfine splitting of 5.8 mT. The energy of the intercage C-C bond was estimated to be 234±7 kJ mol-1 , the highest value among negatively charged fullerene dimers. The EPR spectra of crystalline (Bu3 MeP+ )3 (Sc3 N@Ih -C80 .- )3 ⋅C6 H4 Cl2 (6) are presented for the first time. The salt shows an asymmetric EPR signal, which could be fitted by three lines. Two lines were attributed to Sc3 N@Ih -C80 .- . Hyperfine splitting is manifested above 180 K due to the hyperfine interaction of the electron spin with the three scandium atoms (a total of 22 lines with an average splitting of 5.32 mT are observed at 220 K). Furthermore, each of the 22 lines is additionally split into six lines with an average separation of 0.82 mT. The large splitting indicates intrinsic charge and spin density transfer from the fullerene cage to the Sc3 N cluster. Both the monomeric and dimeric Sc3 N@Ih -C80 - anions show an intrinsic shift of the IR bands attributed to the Sc3 N cluster and new bands corresponding to these species appear in the NIR range of their UV/Vis/NIR spectra, which allows these anions to be distinguished from neutral species.
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Affiliation(s)
- Dmitri V Konarev
- Department of Kinetics and Catalysis, Institute of Problems of Chemical Physics RAS, 142432, Moscow, Russian Federation
| | - Alexey A Popov
- Leibniz Institute for Solid State and Materials Research, Helmholtzstraße 20, 01069, Dresden, Germany
| | - Leokadiya V Zorina
- Institute of Solid State Physics RAS, 142432, Moscow, Russian Federation
| | - Salavat S Khasanov
- Institute of Solid State Physics RAS, 142432, Moscow, Russian Federation
| | - Rimma N Lyubovskaya
- Department of Kinetics and Catalysis, Institute of Problems of Chemical Physics RAS, 142432, Moscow, Russian Federation
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21
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Liu F, Spree L, Krylov DS, Velkos G, Avdoshenko SM, Popov AA. Single-Electron Lanthanide-Lanthanide Bonds Inside Fullerenes toward Robust Redox-Active Molecular Magnets. Acc Chem Res 2019; 52:2981-2993. [PMID: 31571482 PMCID: PMC6796827 DOI: 10.1021/acs.accounts.9b00373] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A characteristic phenomenon of lanthanide-fullerene interactions is the transfer of metal valence electrons to the carbon cage. With early lanthanides such as La, a complete transfer of six valence electrons takes place for the metal dimers encapsulated in the fullerene cage. However, the low energy of the σ-type Ln-Ln bonding orbital in the second half of the lanthanide row limits the Ln2 → fullerene transfer to only five electrons. One electron remains in the Ln-Ln bonding orbital, whereas the fullerene cage with a formal charge of -5 is left electron-deficient. Such Ln2@C80 molecules are unstable in the neutral form but can be stabilized by substitution of one carbon atom by nitrogen to give azafullerenes Ln2@C79N or by quenching the unpaired electron on the fullerene cage by reacting it with a chemical such as benzyl bromide, transforming one sp2 carbon into an sp3 carbon and yielding the monoadduct Ln2@C80(CH2Ph). Because of the presence of the Ln-Ln bonding molecular orbital with one electron, the Ln2@C79N and Ln2@C80(R) molecules feature a unique single-electron Ln-Ln bond and an unconventional +2.5 oxidation state of the lanthanides. In this Account, which brings together metallofullerenes, molecular magnets, and lanthanides in unconventional valence states, we review the progress in the studies of dimetallofullerenes with single-electron Ln-Ln bonds and highlight the consequences of the unpaired electron residing in the Ln-Ln bonding orbital for the magnetic interactions between Ln ions. Usually, Ln···Ln exchange coupling in polynuclear lanthanide compounds is weak because of the core nature of 4f electrons. However, when interactions between Ln centers are mediated by a radical bridge, stronger coupling may be achieved because of the diffuse nature of radical-based orbitals. Ultimately, when the role of a radical bridge is played by a single unpaired electron in the Ln-Ln bonding orbital, the strength of the exchange coupling is increased dramatically. Giant exchange coupling in endohedral Ln2 dimers is combined with a rather strong axial ligand field exerted on the lanthanide ions by the fullerene cage and the excess electron density localized between two Ln ions. As a result, Ln2@C79N and Ln2@C80(CH2Ph) compounds exhibit slow relaxation of magnetization and exceptionally high blocking temperatures for Ln = Dy and Tb. At low temperatures, the [Ln3+-e-Ln3+] fragment behaves as a single giant spin. Furthermore, the Ln-Ln bonding orbital in dimetallofullerenes is redox-active, which allows its population to be changed by electrochemical reactions, thus changing the magnetic properties because the change in the number of electrons residing in the Ln-Ln orbital affects the magnetic structure of the molecule.
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Affiliation(s)
- Fupin Liu
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany
| | - Lukas Spree
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany
| | - Denis S. Krylov
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Ewha Womans University, Seoul 03760, Republic of Korea
| | - Georgios Velkos
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany
| | - Stanislav M. Avdoshenko
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany
| | - Alexey A. Popov
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstraße 20, 01069 Dresden, Germany
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22
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Abstract
Implementation of modern Quantum Technologies might benefit from the remarkable quantum properties shown by molecular spin systems. In this Perspective, we highlight the role that molecular chemistry can have in the current second quantum revolution, i.e., the use of quantum physics principles to create new quantum technologies, in this specific case by means of molecular components. Herein, we briefly review the current status of the field by identifying the key advances recently made by the molecular chemistry community, such as for example the design of molecular spin qubits with long spin coherence and the realization of multiqubit architectures for quantum gates implementation. With a critical eye to the current state-of-the-art, we also highlight the main challenges needed for the further advancement of the field toward quantum technologies development.
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Affiliation(s)
- Matteo Atzori
- Laboratoire National des Champs Magnétiques Intenses, UPR 3228-CNRS , F-38042 Grenoble , France
| | - Roberta Sessoli
- Dipartimento di Chimica "Ugo Schiff" & INSTM RU , Università degli Studi di Firenze , I-50019 Sesto Fiorentino , Italy
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23
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Yoshida T, Izuogu DC, Zhang HT, Cosquer G, Abe H, Wernsdorfer W, Breedlove BK, Yamashita M. Ln-Pt electron polarization effects on the magnetic relaxation of heterometallic Ho- and Er-Pt complexes. Dalton Trans 2019; 48:7144-7149. [PMID: 30265262 DOI: 10.1039/c8dt03338b] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Heterometallic Ln-Pt complexes, with the formula [Ln2Pt3(H2O)2(SAc)12] (Ln = Ho(1), Er(2); SAc = thioacetate), were synthesized. From natural bond orbital (NBO) and local orbital locator (LOL) analyses and X-ray absorption fine structure (XAFS) measurements, it was clear that the Ln-Pt interactions or electron polarization occurred. Butterfly-type hysteresis was observed for both 1 and 2. 1 and 2 underwent field-induced slow magnetic relaxation up to 4 K. These magnetic properties were induced by Ln-Pt electron polarization.
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Affiliation(s)
- Takefumi Yoshida
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aza-Aoba, Aramaki, Sendai 980-8578, Japan.
| | - David C Izuogu
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aza-Aoba, Aramaki, Sendai 980-8578, Japan. and Department of Pure & Industrial Chemistry, University of Nigeria, 410001, Nsukka, Nigeria
| | - Hai-Tao Zhang
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aza-Aoba, Aramaki, Sendai 980-8578, Japan.
| | - Goulven Cosquer
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aza-Aoba, Aramaki, Sendai 980-8578, Japan.
| | - Hitoshi Abe
- Institute of Materials Structure Science High Energy Accelerator Research Organization (KEK) 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan and Department of Materials Structure Science, School of High Energy Accelerator Science, SOKENDAI(the Graduate University for Advanced Studies) 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - Wolfgang Wernsdorfer
- Physikalisches Institut, Karlsruher Institut für Technologie Wolfgang-Gaede-Str. 1, D-76131 Karlsruhe, Germany and CNRS and Université Grenoble Alpes, Institut Néel, 38042 Grenoble, France
| | - Brian K Breedlove
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aza-Aoba, Aramaki, Sendai 980-8578, Japan.
| | - Masahiro Yamashita
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aza-Aoba, Aramaki, Sendai 980-8578, Japan. and WPI-Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Sendai 980-8577, Japan and School of Materials Science and Engineering, Nankai University, Tianjin 300350, China
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24
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Velkos G, Krylov DS, Kirkpatrick K, Spree L, Dubrovin V, Büchner B, Avdoshenko SM, Bezmelnitsyn V, Davis S, Faust P, Duchamp J, Dorn HC, Popov AA. Hohe Block‐Temperatur der Magnetisierung und herausragende Koerzitivfeldstärke im Azafulleren Tb
2
@C
79
N mit einer Einelektronen‐Terbium‐Terbium‐Bindung. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201900943] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Georgios Velkos
- Leibniz Institut für Festkörper- und Werkstoffforschung Helmholtzstraße 20 01069 Dresden Deutschland
| | - Denis S. Krylov
- Leibniz Institut für Festkörper- und Werkstoffforschung Helmholtzstraße 20 01069 Dresden Deutschland
- Center for Quantum NanoscienceInstitute for Basic Science (IBS) Seoul Republic of Korea
| | - Kyle Kirkpatrick
- Department of ChemistryVirginia Polytechnic Institute and State University Blacksburg Virginia 24061 USA
| | - Lukas Spree
- Leibniz Institut für Festkörper- und Werkstoffforschung Helmholtzstraße 20 01069 Dresden Deutschland
| | - Vasilii Dubrovin
- Leibniz Institut für Festkörper- und Werkstoffforschung Helmholtzstraße 20 01069 Dresden Deutschland
| | - Bernd Büchner
- Leibniz Institut für Festkörper- und Werkstoffforschung Helmholtzstraße 20 01069 Dresden Deutschland
| | - Stanislav M. Avdoshenko
- Leibniz Institut für Festkörper- und Werkstoffforschung Helmholtzstraße 20 01069 Dresden Deutschland
| | - Valeriy Bezmelnitsyn
- Luna nanoWorks, a Division ofLuna Innovation Inc. 521 Bridge St Danville Virginia USA
| | - Sean Davis
- Luna nanoWorks, a Division ofLuna Innovation Inc. 521 Bridge St Danville Virginia USA
| | - Paul Faust
- Department of ChemistryVirginia Polytechnic Institute and State University Blacksburg Virginia 24061 USA
| | - James Duchamp
- Department of ChemistryVirginia Polytechnic Institute and State University Blacksburg Virginia 24061 USA
| | - Harry C. Dorn
- Department of ChemistryVirginia Polytechnic Institute and State University Blacksburg Virginia 24061 USA
| | - Alexey A. Popov
- Leibniz Institut für Festkörper- und Werkstoffforschung Helmholtzstraße 20 01069 Dresden Deutschland
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25
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Velkos G, Krylov DS, Kirkpatrick K, Spree L, Dubrovin V, Büchner B, Avdoshenko SM, Bezmelnitsyn V, Davis S, Faust P, Duchamp J, Dorn HC, Popov AA. High Blocking Temperature of Magnetization and Giant Coercivity in the Azafullerene Tb 2 @C 79 N with a Single-Electron Terbium-Terbium Bond. Angew Chem Int Ed Engl 2019; 58:5891-5896. [PMID: 30786125 PMCID: PMC6519270 DOI: 10.1002/anie.201900943] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 02/19/2019] [Indexed: 11/09/2022]
Abstract
The azafullerene Tb2 @C79 N is found to be a single-molecule magnet with a high 100-s blocking temperature of magnetization of 24 K and large coercivity. Tb magnetic moments with an easy-axis single-ion magnetic anisotropy are strongly coupled by the unpaired spin of the single-electron Tb-Tb bond. Relaxation of magnetization in Tb2 @C79 N below 15 K proceeds via quantum tunneling of magnetization with the characteristic time τQTM =16 462±1230 s. At higher temperature, relaxation follows the Orbach mechanism with a barrier of 757±4 K, corresponding to the excited states, in which one of the Tb spins is flipped.
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Affiliation(s)
- Georgios Velkos
- Leibniz Institute for Solid State and Materials Research, Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Denis S Krylov
- Leibniz Institute for Solid State and Materials Research, Helmholtzstrasse 20, 01069, Dresden, Germany.,Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul, Republic of Korea
| | - Kyle Kirkpatrick
- Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24061, USA
| | - Lukas Spree
- Leibniz Institute for Solid State and Materials Research, Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Vasilii Dubrovin
- Leibniz Institute for Solid State and Materials Research, Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Bernd Büchner
- Leibniz Institute for Solid State and Materials Research, Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Stanislav M Avdoshenko
- Leibniz Institute for Solid State and Materials Research, Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Valeriy Bezmelnitsyn
- Luna nanoWorks, a Division of, Luna Innovation Inc., 521 Bridge St, Danville, Virginia, USA
| | - Sean Davis
- Luna nanoWorks, a Division of, Luna Innovation Inc., 521 Bridge St, Danville, Virginia, USA
| | - Paul Faust
- Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24061, USA
| | - James Duchamp
- Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24061, USA
| | - Harry C Dorn
- Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24061, USA
| | - Alexey A Popov
- Leibniz Institute for Solid State and Materials Research, Helmholtzstrasse 20, 01069, Dresden, Germany
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26
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Spree L, Popov AA. Recent advances in single molecule magnetism of dysprosium-metallofullerenes. Dalton Trans 2019; 48:2861-2871. [PMID: 30756104 PMCID: PMC6394203 DOI: 10.1039/c8dt05153d] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Accepted: 01/24/2019] [Indexed: 11/21/2022]
Abstract
This article outlines the magnetic properties of single molecule magnets based on Dy-encapsulating endohedral metallofullerenes. The factors that govern these properties, such as the influence of different non-metal species in clusterfullerenes, the cage size, and cage isomerism are discussed, as well as the recent successful isolation of dimetallofullerenes with unprecedented magnetic properties. Finally, recent advances towards the organization of endohedral metallofullerenes in 1D, 2D, and 3D ordered structures with potential for devices are reviewed.
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Affiliation(s)
- Lukas Spree
- IFW Dresden
,
Helmhotzstraße 20
, 01069 Dresden
, Germany
.
;
| | - Alexey A. Popov
- IFW Dresden
,
Helmhotzstraße 20
, 01069 Dresden
, Germany
.
;
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27
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Liu F, Velkos G, Krylov DS, Spree L, Zalibera M, Ray R, Samoylova NA, Chen CH, Rosenkranz M, Schiemenz S, Ziegs F, Nenkov K, Kostanyan A, Greber T, Wolter AUB, Richter M, Büchner B, Avdoshenko SM, Popov AA. Air-stable redox-active nanomagnets with lanthanide spins radical-bridged by a metal-metal bond. Nat Commun 2019; 10:571. [PMID: 30718550 PMCID: PMC6362165 DOI: 10.1038/s41467-019-08513-6] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 01/11/2019] [Indexed: 12/02/2022] Open
Abstract
Engineering intramolecular exchange interactions between magnetic metal atoms is a ubiquitous strategy for designing molecular magnets. For lanthanides, the localized nature of 4f electrons usually results in weak exchange coupling. Mediating magnetic interactions between lanthanide ions via radical bridges is a fruitful strategy towards stronger coupling. In this work we explore the limiting case when the role of a radical bridge is played by a single unpaired electron. We synthesize an array of air-stable Ln2@C80(CH2Ph) dimetallofullerenes (Ln2 = Y2, Gd2, Tb2, Dy2, Ho2, Er2, TbY, TbGd) featuring a covalent lanthanide-lanthanide bond. The lanthanide spins are glued together by very strong exchange interactions between 4f moments and a single electron residing on the metal–metal bonding orbital. Tb2@C80(CH2Ph) shows a gigantic coercivity of 8.2 Tesla at 5 K and a high 100-s blocking temperature of magnetization of 25.2 K. The Ln-Ln bonding orbital in Ln2@C80(CH2Ph) is redox active, enabling electrochemical tuning of the magnetism. Dilanthanide complexes that possess radical bridges exhibit enhanced magnetic exchange coupling, affording molecular magnets with high blocking temperatures. Here, the authors explore a series of dilanthanide-encapsulated fullerenes where the radical bridge is taken to its limit and the role is played by a single unpaired electron.
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Affiliation(s)
- Fupin Liu
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany.
| | - Georgios Velkos
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Denis S Krylov
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Lukas Spree
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Michal Zalibera
- Institute of Physical Chemistry and Chemical Physics, Slovak University of Technology, Radlinského 9, 81237, Bratislava, Slovakia
| | - Rajyavardhan Ray
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany.,Dresden Center for Computational Materials Science (DCMS), TU Dresden, D-01062, Dresden, Germany
| | - Nataliya A Samoylova
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Chia-Hsiang Chen
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Marco Rosenkranz
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Sandra Schiemenz
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Frank Ziegs
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Konstantin Nenkov
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Aram Kostanyan
- Physik-Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland
| | - Thomas Greber
- Physik-Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland
| | - Anja U B Wolter
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Manuel Richter
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany.,Dresden Center for Computational Materials Science (DCMS), TU Dresden, D-01062, Dresden, Germany
| | - Bernd Büchner
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany
| | - Stanislav M Avdoshenko
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany.
| | - Alexey A Popov
- Leibniz Institute for Solid State and Materials Research (IFW Dresden), Helmholtzstrasse 20, 01069, Dresden, Germany.
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28
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Velloth A, Imamura Y, Hada M. Functionalization of Endohedral Metallofullerenes toward Improving Barrier Height for the Relaxation of Magnetization for Dy 2@C 80-X (X = CF 3, C 3N 3Ph 2). Inorg Chem 2019; 58:1208-1215. [PMID: 30614692 DOI: 10.1021/acs.inorgchem.8b02652] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We theoretically studied the electronic and magnetic properties of the exterior functionalized endohedral metallofullerenes (EMFs) of Gd2@ I h-C80-X (where X is the exterior functional group). Molecular orbital analysis suggests that the presence of unpaired electron on the I h-C80 cage is not favoring the observation of stable species. One of the effective strategies to address this problem is by attaching an exterior functional group to the fullerene cage. Out of the studied exterior functionalized EMFs, we were successful in finding two stable species such as Gd2@ I h-C80-CF3 and Gd2@ I h-C80-C3N3Ph2 with no unpaired spin on the cage. Further, we utilized exterior functional groups such as -CF3 (1) and -C3N3Ph2 (2) to model and to stabilize dinuclear Dy2@ I h-C80 species, and we thoroughly investigated their magnetic properties using ab initio calculations. Within the single-ion paradigm, DyIII ions in 1 and 2 are magnetically anisotropic, and their magnetization-reversal energy barriers are estimated to be ∼698 and ∼705 cm-1, respectively. Furthermore, beyond the single-ion paradigm, i.e., considering a ferromagnetic coupling (∼30 cm-1) between the lanthanide ions and the radical spin, the energy barriers of 1 and 2 are estimated to be 79.8 and 73.0 cm-1, respectively.
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Affiliation(s)
- Archana Velloth
- Department of Chemistry, Graduate School of Science and Engineering , Tokyo Metropolitan University , 1-1 minami-osawa , Hachioji, Tokyo 192-0397 , Japan
| | - Yutaka Imamura
- Department of Chemistry, Graduate School of Science and Engineering , Tokyo Metropolitan University , 1-1 minami-osawa , Hachioji, Tokyo 192-0397 , Japan
| | - Masahiko Hada
- Department of Chemistry, Graduate School of Science and Engineering , Tokyo Metropolitan University , 1-1 minami-osawa , Hachioji, Tokyo 192-0397 , Japan
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29
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Cornia A, Mannini M, Sessoli R, Gatteschi D. Propeller-Shaped Fe4
and Fe3
M Molecular Nanomagnets: A Journey from Crystals to Addressable Single Molecules. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201801266] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Andrea Cornia
- Department of Chemical and Geological Sciences and INSTM Research Unit; University of Modena and Reggio Emilia; 41125 Modena Italy
| | - Matteo Mannini
- Department of Chemistry “Ugo Schiff” and INSTM Research Unit; University of Florence; 50019 Sesto Fiorentino (FI) Italy
| | - Roberta Sessoli
- Department of Chemistry “Ugo Schiff” and INSTM Research Unit; University of Florence; 50019 Sesto Fiorentino (FI) Italy
- Research Area Firenze; Istituto di Chimica dei Composti Organometallici - ICCOM-CNR; 50019 Sesto Fiorentino (FI) Italy
| | - Dante Gatteschi
- Department of Chemistry “Ugo Schiff” and INSTM Research Unit; University of Florence; 50019 Sesto Fiorentino (FI) Italy
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30
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Ayabe T, Costes JP, Vendier L, Geist A, Takeda M, Takahashi M. Contribution of 155Gd Mössbauer data to the study of the magnetic interaction in heterodinuclear 3d–Gd (3d = Cu, Ni) coordination complexes. Dalton Trans 2019; 48:6872-6878. [DOI: 10.1039/c9dt01336a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The observed 155Gd Mössbauer isomer shifts of 3d–Gd complexes give an experimental proof for the participation of 5d Gd orbitals to the magnetic interaction in these 3d–Gd complexes.
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Affiliation(s)
- Takanari Ayabe
- Department of Chemistry
- Faculty of Science
- Toho University
- Chiba 274-8510
- Japan
| | | | | | - Andreas Geist
- Karlsruhe Institute of Technology (KIT)
- Institute for Nuclear Waste Disposal (INE)
- 76021 Karlsruhe
- Germany
| | - Masuo Takeda
- Department of Chemistry
- Faculty of Science
- Toho University
- Chiba 274-8510
- Japan
| | - Masashi Takahashi
- Department of Chemistry
- Faculty of Science
- Toho University
- Chiba 274-8510
- Japan
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