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Paschke F, Erler P, Enenkel V, Gragnaniello L, Fonin M. Bulk-Like Magnetic Signature of Individual Fe 4H Molecular Magnets on Graphene. ACS NANO 2019; 13:780-785. [PMID: 30604971 DOI: 10.1021/acsnano.8b08184] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Single-molecule magnets (SMMs) incorporate key properties that make them promising candidates for the emerging field of spintronics. The challenge to realize ordered SMM arrangements on surfaces and at the same time to preserve the magnetic properties upon interaction with the environment is a crucial point on the way to applications. Here we employ inelastic electron tunneling spectroscopy (IETS) to address the magnetic properties in single Fe4 complexes that are adsorbed in a highly ordered arrangement on graphene/Ir(111). We are able to substantially reduce the influence of both the tunneling tip and the adsorption environment on the Fe4 complex during the measurements by using appropriate tunneling parameters in combination with the flat-lying Fe4H derivative and a weakly interacting surface. This allows us to perform noninvasive IETS studies on these bulky molecules. From the measurements we identify intermultiplet spin transitions and determine the intramolecular magnetic exchange interaction constant on a large number of molecules. Although a considerable scattering of the exchange constant values is observed, the distribution maximum is located at a value that coincides with that of the bulk. Our findings confirm a retained molecular magnetism of the Fe4H complex at the local scale and evaluate the influence of the environment on the magnetic exchange interaction.
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Affiliation(s)
- Fabian Paschke
- Department of Physics , University of Konstanz , 78457 Konstanz , Germany
| | - Philipp Erler
- Department of Physics , University of Konstanz , 78457 Konstanz , Germany
| | - Vivien Enenkel
- Department of Physics , University of Konstanz , 78457 Konstanz , Germany
| | - Luca Gragnaniello
- Department of Physics , University of Konstanz , 78457 Konstanz , Germany
| | - Mikhail Fonin
- Department of Physics , University of Konstanz , 78457 Konstanz , Germany
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Gragnaniello L, Paschke F, Erler P, Schmitt P, Barth N, Simon S, Brune H, Rusponi S, Fonin M. Uniaxial 2D Superlattice of Fe 4 Molecular Magnets on Graphene. NANO LETTERS 2017; 17:7177-7182. [PMID: 29148799 DOI: 10.1021/acs.nanolett.6b05105] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We demonstrate that electrospray deposition enables the fabrication of highly periodic self-assembled arrays of Fe4H single molecule magnets on graphene/Ir(111). The energetic positions of molecular states are probed by means of scanning tunneling spectroscopy, showing pronounced long- and short-ranged spatial modulations, indicating the presence of both locally varying intermolecular as well as adsorption-site dependent molecule-substrate interactions. From the magnetic field dependence of the X-ray magnetic circular dichroism signal, we infer that the magnetic easy axis of each Fe4H molecule is oriented perpendicular to the sample surface and that after the deposition the value of the uniaxial anisotropy is identical to the one in bulk. Our findings therefore suggest that the observed interaction of the molecules with their surrounding does not modify the molecular magnetism, resulting in a two-dimensional array of molecular magnets that retain their bulk magnetic properties.
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Affiliation(s)
| | | | | | | | | | | | - Harald Brune
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL) , Station 3, CH-1015 Lausanne, Switzerland
| | - Stefano Rusponi
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL) , Station 3, CH-1015 Lausanne, Switzerland
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Kiefl E, Mannini M, Bernot K, Yi X, Amato A, Leviant T, Magnani A, Prokscha T, Suter A, Sessoli R, Salman Z. Robust Magnetic Properties of a Sublimable Single-Molecule Magnet. ACS NANO 2016; 10:5663-5669. [PMID: 27139335 DOI: 10.1021/acsnano.6b01817] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The organization of single-molecule magnets (SMMs) on surfaces via thermal sublimation is a prerequisite for the development of future devices for spintronics exploiting the richness of properties offered by these magnetic molecules. However, a change in the SMM properties due to the interaction with specific surfaces is usually observed. Here we present a rare example of an SMM system that can be thermally sublimated on gold surfaces while maintaining its intact chemical structure and magnetic properties. Muon spin relaxation and ac susceptibility measurements are used to demonstrate that, unlike other SMMs, the magnetic properties of this system in thin films are very similar to those in the bulk, throughout the full volume of the film, including regions near the metal and vacuum interfaces. These results exhibit the robustness of chemical and magnetic properties of this complex and provide important clues for the development of nanostructures based on SMMs.
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Affiliation(s)
- Evan Kiefl
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut , CH-5232 Villigen PSI, Switzerland
| | - Matteo Mannini
- Department of Chemistry "Ugo Schiff", University of Florence & INSTM RU Firenze , Via della Lastruccia 3-13, 50019 Sesto Fiorentino, Italy
| | - Kevin Bernot
- INSA, ISCR, UMR 6226, F-35708 RENNES , 20 Avenue des Buttes de Coësmes CS70839, 35708 Rennes Cedex, France
| | - Xiaohui Yi
- INSA, ISCR, UMR 6226, F-35708 RENNES , 20 Avenue des Buttes de Coësmes CS70839, 35708 Rennes Cedex, France
| | - Alex Amato
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut , CH-5232 Villigen PSI, Switzerland
| | - Tom Leviant
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut , CH-5232 Villigen PSI, Switzerland
- Department of Physics, Technion - Israel Institute of Technology , Haifa 32000, Israel
| | - Agnese Magnani
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena & INSTM RU Siena , Via A. Moro, 2 53100 Siena, Italy
| | - Thomas Prokscha
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut , CH-5232 Villigen PSI, Switzerland
| | - Andreas Suter
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut , CH-5232 Villigen PSI, Switzerland
| | - Roberta Sessoli
- Department of Chemistry "Ugo Schiff", University of Florence & INSTM RU Firenze , Via della Lastruccia 3-13, 50019 Sesto Fiorentino, Italy
| | - Zaher Salman
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut , CH-5232 Villigen PSI, Switzerland
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Erler P, Schmitt P, Barth N, Irmler A, Bouvron S, Huhn T, Groth U, Pauly F, Gragnaniello L, Fonin M. Highly Ordered Surface Self-Assembly of Fe₄ Single Molecule Magnets. NANO LETTERS 2015; 15:4546-52. [PMID: 26086677 DOI: 10.1021/acs.nanolett.5b01120] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Single molecule magnets (SMMs) have attracted considerable attention due to low-temperature magnetic hysteresis and fascinating quantum effects. The investigation of these properties requires the possibility to deposit well-defined monolayers or spatially isolated molecules within a well-controlled adsorption geometry. Here we present a successful fabrication of self-organized arrays of Fe4 SMMs on hexagonal boron nitride (h-BN) on Rh(111) as template. Using a rational design of the ligand shell optimized for surface assembly and electrospray as a gentle deposition method, we demonstrate how to obtain ordered arrays of molecules forming perfect hexagonal superlattices of tunable size, from small islands to an almost perfect monolayer. High-resolution low temperature scanning tunneling microscopy (STM) reveals that the Fe4 molecule adsorbs on the substrate in a flat geometry, meaning that its magnetic easy axis is perpendicular to the surface. By scanning tunneling spectroscopy (STS) and density functional theory (DFT) calculations, we infer that the majority- and minority-spin components of the spin-split lowest unoccupied molecular orbital (LUMO) can be addressed separately on a submolecular level.
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Affiliation(s)
- Philipp Erler
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | | | - Nicole Barth
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Andreas Irmler
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Samuel Bouvron
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | | | | | - Fabian Pauly
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Luca Gragnaniello
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Mikhail Fonin
- †Department of Physics and ‡Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
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MacFarlane WA. Implanted-ion βNMR: A new probe for nanoscience. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2015; 68-69:1-12. [PMID: 25863576 DOI: 10.1016/j.ssnmr.2015.02.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 02/09/2015] [Accepted: 02/11/2015] [Indexed: 06/04/2023]
Abstract
NMR detected by radioactive beta decay, β-NMR, is undergoing a renaissance largely due to the availability of high intensity low energy beams of the most common probe ion, Li+8, and dedicated facilities for materials research. The radioactive detection scheme, combined with the low energy ion beam, enable depth resolved NMR measurements in crystals, thin films and multilayers on depth scales of 2-200 nm. After a brief historical introduction, technical aspects of implanted-ion β-NMR are presented, followed by a review of recent applications to a wide range of solids.
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Affiliation(s)
- W A MacFarlane
- Chemistry Department, University of British Columbia, 2036 Main Mall, Vancouver, Canada V6T 1Z1.
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Garcia Ruiz RF, Bissell M, Gottberg A, Stachura M, Hemmingsen L, Neyens G, Severijns N. Perspectives for the VITO beam line at ISOLDE, CERN. EPJ WEB OF CONFERENCES 2015. [DOI: 10.1051/epjconf/20159307004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Bellido E, González-Monje P, Repollés A, Jenkins M, Sesé J, Drung D, Schurig T, Awaga K, Luis F, Ruiz-Molina D. Mn12 single molecule magnets deposited on μ-SQUID sensors: the role of interphases and structural modifications. NANOSCALE 2013; 5:12565-12573. [PMID: 24172940 DOI: 10.1039/c3nr02359a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Direct measurements of the linear ac susceptibility and magnetic relaxation of a few Mn12 monolayers deposited on a μ-SQUID sensor are reported. In order to integrate the molecules into the device, DPN has been the technique of choice. It enabled the structuration of the molecules on the most sensitive areas of the sensor without the need for any previous functionalization of the molecule or the substrate, while controlling the number of molecular units deposited on each array. The measurements reveal that their characteristic SMM behaviour is lost, a fact that is attributed to molecular distortions originated by the strong surface tensions arising at the molecular interphases.
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Affiliation(s)
- Elena Bellido
- ICN2 Institut Catala de Nanociencia i Nanotecnologia, Campus UAB, 08193 Bellaterra (Barcelona), Spain.
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Sun K, Park K, Xie J, Luo J, Yuan H, Xiong Z, Wang J, Xue Q. Direct observation of molecular orbitals in an individual single-molecule magnet Mn12 on Bi(111). ACS NANO 2013; 7:6825-6830. [PMID: 23829481 DOI: 10.1021/nn401827h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Single-molecule nanomagnets have unique quantum properties, and their potential applications require characterization and accessibility of individual single-molecule magnets on various substrates. We develop a gentle tip-deposition method to bring individual prototype single-molecule magnets, manganese-12-acetate (Mn12) molecules, onto the semimetallic Bi(111) surface without linker molecules, using low-temperature scanning tunneling microscopy. We are able to identify both the almost flat-lying and side-lying orientations of Mn12 molecules at 4.5 K. Energy-resolved spectroscopic mapping enables the first observation of several molecular orbitals of individual Mn12 molecules in real space, which is consistent with density functional theory calculations. Both experimental and theoretical results suggest that an energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of the almost flat-lying Mn12 is only 40% of such a gap for an isolated (free) Mn12 molecule, which is caused by charge transfer from the metallic surface states of Bi to the Mn12. Despite the reduction of this gap, STM images show that the local lattices of Bi(111) covered with Mn12 remain essentially intact, indicating that Mn12-Bi interactions are not strong. Our findings open an avenue to address directly the local structural and electronic properties of individual single-molecule magnets on solid substrates.
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Affiliation(s)
- Kai Sun
- School of Physical Science and Technology & MOE Key Lab Luminescence & Real Time Analysis, Southwest University, Chongqing 400715, China
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Salman Z, Ofer O, Radovic M, Hao H, Ben Shalom M, Chow KH, Dagan Y, Hossain MD, Levy CDP, Macfarlane WA, Morris GM, Patthey L, Pearson MR, Saadaoui H, Schmitt T, Wang D, Kiefl RF. Nature of weak magnetism in SrTiO3/LaAlO3 multilayers. PHYSICAL REVIEW LETTERS 2012; 109:257207. [PMID: 23368496 DOI: 10.1103/physrevlett.109.257207] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Revised: 09/20/2012] [Indexed: 06/01/2023]
Abstract
We report the observation of weak magnetism in superlattices of LaAlO(3)/SrTiO(3) using β-detected nuclear magnetic resonance. The spin lattice relaxation rate of ^{8}Li in superlattices with a spacer layers of 8 and 6 unit cells of LaAlO(3) exhibits a strong peak near ~35 K, whereas no such peak is observed in a superlattice with spacer layer thickness of 3 unit cells. We attribute the observed temperature dependence to slowing down of weakly coupled electronic moments at the LaAlO(3)/SrTiO(3) interface. These results show that the magnetism at the interface depends strongly on the thickness of the spacer layer, and that a minimal thickness of ~4-6 unit cells is required for the appearance of magnetism. A simple model is used to determine that the observed relaxation is due to small fluctuating moments (~0.002μ(B)) in the two samples with a larger LaAlO(3) spacer thickness.
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Affiliation(s)
- Z Salman
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland.
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Hofmann A, Salman Z, Mannini M, Amato A, Malavolti L, Morenzoni E, Prokscha T, Sessoli R, Suter A. Depth-dependent spin dynamics in thin films of TbPc2 nanomagnets explored by low-energy implanted muons. ACS NANO 2012; 6:8390-8396. [PMID: 22917162 DOI: 10.1021/nn3031673] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We present measurements of the magnetic properties of thin film TbPc(2) single-molecule magnets evaporated on a gold substrate and compare them to those in bulk. Zero-field muon spin relaxation measurements were used to determine the molecular spin fluctuation rate of TbPc(2) as a function of temperature. At low temperature, we find that the fluctuations in films are much faster than in bulk and depend strongly on the distance between the molecules and the Au substrate. We measure a molecular spin correlation time that varies between 1.4 μs near the substrate and 6.6 μs far away from it. We attribute this behavior to differences in the packing of the magnetic cores, which change gradually on the scale of ~10-20 nm away from the TbPc(2)/Au interface.
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Affiliation(s)
- Andrea Hofmann
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
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Domingo N, Bellido E, Ruiz-Molina D. Advances on structuring, integration and magnetic characterization of molecular nanomagnets on surfaces and devices. Chem Soc Rev 2012; 41:258-302. [DOI: 10.1039/c1cs15096k] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Mas-Torrent M, Crivillers N, Rovira C, Veciana J. Attaching persistent organic free radicals to surfaces: how and why. Chem Rev 2011; 112:2506-27. [PMID: 22188381 DOI: 10.1021/cr200233g] [Citation(s) in RCA: 144] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Marta Mas-Torrent
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Spain.
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Cummings SP, Savchenko J, Ren T. Functionalization of flat Si surfaces with inorganic compounds—Towards molecular CMOS hybrid devices. Coord Chem Rev 2011. [DOI: 10.1016/j.ccr.2010.12.030] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Gatteschi D, Cornia A, Mannini M, Sessoli R. Organizing and Addressing Magnetic Molecules. Inorg Chem 2009; 48:3408-19. [DOI: 10.1021/ic8013283] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Dante Gatteschi
- Department of Chemistry and INSTM (UdR Firenze), University of Florence, via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy, Department of Chemistry and INSTM (UdR Modena e Reggio Emilia), University of Modena and Reggio Emilia, via G. Campi 183, 41100 Modena, Italy, and ISTM-CNR, (UdR Firenze), University of Florence, via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy
| | - Andrea Cornia
- Department of Chemistry and INSTM (UdR Firenze), University of Florence, via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy, Department of Chemistry and INSTM (UdR Modena e Reggio Emilia), University of Modena and Reggio Emilia, via G. Campi 183, 41100 Modena, Italy, and ISTM-CNR, (UdR Firenze), University of Florence, via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy
| | - Matteo Mannini
- Department of Chemistry and INSTM (UdR Firenze), University of Florence, via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy, Department of Chemistry and INSTM (UdR Modena e Reggio Emilia), University of Modena and Reggio Emilia, via G. Campi 183, 41100 Modena, Italy, and ISTM-CNR, (UdR Firenze), University of Florence, via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy
| | - Roberta Sessoli
- Department of Chemistry and INSTM (UdR Firenze), University of Florence, via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy, Department of Chemistry and INSTM (UdR Modena e Reggio Emilia), University of Modena and Reggio Emilia, via G. Campi 183, 41100 Modena, Italy, and ISTM-CNR, (UdR Firenze), University of Florence, via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy
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Ghirri A, Candini A, Evangelisti M, Gazzadi GC, Volatron F, Fleury B, Catala L, David C, Mallah T, Affronte M. Magnetic imaging of cyanide-bridged co-ordination nanoparticles grafted on FIB-patterned Si substrates. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2008; 4:2240-2246. [PMID: 19016497 DOI: 10.1002/smll.200800897] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Prussian blue CsNiCr nanoparticles are used to decorate selected portions of a Si substrate. For successful grafting to take place, the Si surface needs first to be chemically functionalized. Low-dose focused ion beam patterning on uniformly functionalized surfaces selects those portions that will not participate in the grafting process. Step-by-step control is assured by atomic force and high-resolution scanning electron microscopy, revealing a submonolayer distribution of the grafted nanoparticles. By novel scanning Hall-probe microscopy, an in-depth investigation of the magnetic response of the nanoparticles to varying temperature and applied magnetic field is provided. The magnetic images acquired suggest that low-temperature canted ferromagnetism is found in the grafted nanoparticles, similar to what is observed in the equivalent bulk material.
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Affiliation(s)
- Alberto Ghirri
- CNR-INFM National Research Center on nanoStructures and bioSystems at Surfaces (S3) and Dipartimento di Fisica, Università di Modena e Reggio Emilia, via Campi 213/a, 41100 Modena, Italy.
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Xu M, Hossain MD, Saadaoui H, Parolin TJ, Chow KH, Keeler TA, Kiefl RF, Morris GD, Salman Z, Song Q, Wang D, MacFarlane WA. Proximal magnetometry in thin films using betaNMR. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2008; 191:47-55. [PMID: 18162424 DOI: 10.1016/j.jmr.2007.11.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2007] [Revised: 11/22/2007] [Accepted: 11/27/2007] [Indexed: 05/25/2023]
Abstract
Low energy ion implantation of hyperpolarized radioactive magnetic resonance probes allows the NMR study of thin film heterostructures by enabling depth-resolved measurements on a nanometer lengthscale. By stopping the probe ions in a layer adjacent to a layer of interest, it is possible to study magnetic fields proximally. Here we show that, in the simplest case of a uniformly magnetized layer, this yields an unperturbed in situ frequency reference. We also discuss demagnetization contributions to measured shifts for this case. With a simple illustrative calculation, we show how a nonuniformly magnetized layer causes a strongly depth-dependent line broadening in an adjacent layer. We then give some experimental examples of resonance line broadening in heterostructures.
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Affiliation(s)
- M Xu
- TRIUMF, 4004 Wesbrook Mall, Vancouver, Canada V6T 2A3
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Moroni R, Buzio R, Chincarini A, Valbusa U, de Mongeot FB, Bogani L, Caneschi A, Sessoli R, Cavigli L, Gurioli M. Optically addressable single molecule magnet behaviour of vacuum-sprayed ultrathin films. ACTA ACUST UNITED AC 2008. [DOI: 10.1039/b712913k] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Pineider F, Mannini M, Sessoli R, Caneschi A, Barreca D, Armelao L, Cornia A, Tondello E, Gatteschi D. Solvent effects on the adsorption and self-organization of Mn12 on Au(111). LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:11836-11843. [PMID: 17939691 DOI: 10.1021/la7016837] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A sulfur-containing single molecule magnet, [Mn12O12(O2CC6H4SCH3)16(H2O)4], was assembled from solution on a Au(111) surface affording both submonolayer and monolayer coverages. The adsorbate morphology and the degree of coverage were inspected by scanning tunneling microscopy (STM), while X-ray photoelectron spectroscopy (XPS) allowed the determination of the chemical nature of the adsorbate on a qualitative and quantitative basis. The properties of the adsorbates were found to be strongly dependent on the solvent used to dissolve the magnetic complex. In particular, systems prepared from tetrahydrofuran solutions gave arrays of isolated and partially ordered clusters on the gold substrate, while samples prepared from dichloromethane exhibited a homogeneous monolayer coverage of the whole Au(111) surface. These findings are relevant to the optimization of magnetic addressing of single molecule magnets on surfaces.
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Affiliation(s)
- Francesco Pineider
- Dipartimento di Chimica, Università di Firenze and INSTM, Via della, Lastruccia 3, 50019 Sesto Fiorentino, Italy
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