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Roncero-Barrero C, Ribas-Ariño J, Moreira IDPR, Deumal M. Magnetic coupling and spin ordering in bisdithiazolyl, thiaselenazolyl, and bisdiselenazolyl molecular materials. Dalton Trans 2022; 51:13032-13045. [PMID: 35968924 DOI: 10.1039/d2dt01340a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The use of purely organic materials is a promising approach for the miniaturization of devices due to their interesting optical, electronic and magnetic properties. Bisdithiazolyl-based bisDTA compounds have emerged as promising candidates for radical-based single component conductors exhibiting simultaneously magnetic properties. Our computational work focuses on the intriguing magnetism of 4 isostructural pyridine-bridged bisDTA-multifunctional materials triggered by their magnetic and conducting properties being strongly dependent on the different S/Se ratios in the neutral radical skeleton: specifically, bisdithiazolyl (S,S) displays no magnetic order at low temperatures, thiaselenazolyl (Se,S) exhibits spin-canted antiferromagnetism (AFM), and both (S,Se) and bisdiselenazolyl (Se,Se) behave as bulk ferromagnets (FM). Our results reveal that (1) the magnetic response depends on the existence of an intricate network of both AFM and FM spin exchange JAB couplings between neighbouring radicals; and (2) the structural arrangement of π-stacked pairs of radicals sits on a point in the configurational space that is very close to a crossover region where JAB switches from AFM to FM. Indeed, for bulk FM, the experimental response is only accounted for when considering an ab initio optimised crystal structure able to portray adequately the electronic structure of bisDTAs in the region close to the temperature at which magnetic ordering emerges. Magneto-structural correlation maps show the large sensitivity of JAB to very small structural changes with temperature along the π-stacks that lead to drastic changes in the magnetic properties. Clearly, the understanding of magnetism in the title bisDTA compounds is decisive to rationally tailor the properties of multifunctional materials by subtle structural modifications of their crystal packing.
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Affiliation(s)
- C Roncero-Barrero
- Secció Química Física, Dept. Ciència de Materials i Química Física, and Institut de Química Teòrica i Computacional IQTCUB, Universitat de Barcelona, Martí i Franquès, 1, E08028 Barcelona, Spain.
| | - J Ribas-Ariño
- Secció Química Física, Dept. Ciència de Materials i Química Física, and Institut de Química Teòrica i Computacional IQTCUB, Universitat de Barcelona, Martí i Franquès, 1, E08028 Barcelona, Spain.
| | - I de P R Moreira
- Secció Química Física, Dept. Ciència de Materials i Química Física, and Institut de Química Teòrica i Computacional IQTCUB, Universitat de Barcelona, Martí i Franquès, 1, E08028 Barcelona, Spain.
| | - M Deumal
- Secció Química Física, Dept. Ciència de Materials i Química Física, and Institut de Química Teòrica i Computacional IQTCUB, Universitat de Barcelona, Martí i Franquès, 1, E08028 Barcelona, Spain.
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2
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Roncero-Barrero C, Ribas-Ariño J, Deumal M, Moreira IDPR. Electronic structure and magnetic coupling in selenium substituted pyridine-bridged bisdithiazolyl multifunctional molecular materials. Phys Chem Chem Phys 2022; 24:12196-12207. [PMID: 35551353 DOI: 10.1039/d2cp00415a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Bisdithiazolyl radicals have furnished in recent years multiple examples of molecular materials with promising conductive and magnetic properties. The electronic band structure and magnetic ordering in four different isostructural pyridine-bridged bisdithiazolyl and Selenium substituted compounds have been studied by means of hybrid DFT based methods as implemented in the CRYSTAL code. The full rationalization of the properties of these multifunctional magnetic molecular materials requires a careful description of their complex open-shell electronic structure. The results describe the systems as narrow band (0.2-0.3 eV dispersion) open-shell semiconductors with a gap of 1.15-1.40 eV between the valence and conducting bands. The bands defining the insulating gap are dominated by orbital contributions arising from the heteroatoms sitting in the outer rings. A low energy closed-shell metallic solution is found at 0.25-0.35 eV above the magnetic solutions thus suggesting a complex mechanism for electric conduction with band and hopping contributions. The observed trend of the conductivity is in line with the variation of the insulating gap but more rigorous modelling is required to take into account the details of the band structure of the systems. For all the systems the spin density is well localised on the molecular units and is independent of the magnetic solution. Thus the system can be described as an ensemble of well-defined S = 1/2 magnetic centres using a two-body Heisenberg-Dirac-van Vleck spin Hamiltonian. The lowest energy electronic solutions are in line with the observed magnetic behaviour at low temperature. The set of competing magnetic exchange interactions that emerges from using a suitable mapping to consistently describe the low energy magnetic solutions explains the variety of magnetic responses (absence of long-range magnetic order, antiferromagnetism or ferromagnetism) of the four studied compounds at low temperatures.
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Affiliation(s)
- Cristina Roncero-Barrero
- Departament de Ciència de Materials i Química Física, Universitat de Barcelona, c/Martí i Franquès 1-11, 08028 Barcelona, Spain.,Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, c/Martí i Franquès 1-11, 08028 Barcelona, Spain
| | - Jordi Ribas-Ariño
- Departament de Ciència de Materials i Química Física, Universitat de Barcelona, c/Martí i Franquès 1-11, 08028 Barcelona, Spain.,Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, c/Martí i Franquès 1-11, 08028 Barcelona, Spain
| | - Mercè Deumal
- Departament de Ciència de Materials i Química Física, Universitat de Barcelona, c/Martí i Franquès 1-11, 08028 Barcelona, Spain.,Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, c/Martí i Franquès 1-11, 08028 Barcelona, Spain
| | - Ibério de P R Moreira
- Departament de Ciència de Materials i Química Física, Universitat de Barcelona, c/Martí i Franquès 1-11, 08028 Barcelona, Spain.,Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, c/Martí i Franquès 1-11, 08028 Barcelona, Spain
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3
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Hill MC, Lough AJ, Gossage RA. Heteroatom Exchange Chemistry in (Z)-1-R-2-(4’,4’-dimethyl)-2’-oxazolin-2’yl)-eth-1-en-1-ols: Access to Chelate-Stabilized Thioester Analogues of Dithiooxophosphoranes. CHEM LETT 2021. [DOI: 10.1246/cl.210702] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Matthew C. Hill
- Department of Chemistry & Biology, Ryerson University, 350 Victoria Street, Toronto ON M5B 2K3 Canada
| | - Alan J. Lough
- X-ray Laboratory, Department of Chemistry, University of Toronto, Toronto ON M5S 3H6 Canada
| | - Robert A. Gossage
- Department of Chemistry & Biology, Ryerson University, 350 Victoria Street, Toronto ON M5B 2K3 Canada
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4
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Benzo[1,2,3]dithiazole Compounds: A History of Synthesis and Their Renewed Applicability in Materials and Synthetic Chemistry, Originating from the Herz Reaction. REACTIONS 2021. [DOI: 10.3390/reactions2030013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The benzo[1,2,3]dithiazole is a unique heteroaromatic functionality whose conjugated profile instils some fascinating electronic properties. This has been historically recognized in the design and manufacture of organic dyes early last century. Although, with the benefit of increased diagnostic techniques and improved understanding, these structures are attracting greater attention in additional research settings, including applications as organic radicals and semiconductors. In addition, the benzodithiazole functionality has been shown to be a valuable synthetic intermediate in the preparation of a variety of other privileged aromatic and heteroaromatic targets, many of which are important APIs. In this review, the authors aim to critically analyse the potential applicability of these compounds to the fields of not only small-scale laboratory synthetic and medicinal chemistry but also commercial-scale processes and increasingly materials chemistry.
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Tiekink ERT. Zero-, one-, two- and three-dimensional supramolecular architectures sustained by Se …O chalcogen bonding: A crystallographic survey. Coord Chem Rev 2021; 427:213586. [PMID: 33100367 PMCID: PMC7568495 DOI: 10.1016/j.ccr.2020.213586] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 09/02/2020] [Indexed: 12/20/2022]
Abstract
The Cambridge Structural Database was evaluated for crystals containing Se…O chalcogen bonding interactions. These secondary bonding interactions are found to operate independently of complementary intermolecular interactions in about 13% of the structures they can potentially form. This number rises significantly when more specific interactions are considered, e.g. Se…O(carbonyl) interactions occur in 50% of cases where they can potentially form. In about 55% of cases, the supramolecular assemblies sustained by Se…O(oxygen) interactions are one-dimensional architectures, with the next most prominent being zero-dimensional assemblies, at 30%.
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Affiliation(s)
- Edward R T Tiekink
- Research Centre for Crystalline Materials, School of Science and Technology, 5 Jalan Universiti, Sunway University, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia
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Reddy IR, Tarafder K. Theoretical Investigations of Electronic Structure and Magnetic and Optical Properties of Transition-Metal Dinuclear Molecules. ACS OMEGA 2020; 5:24520-24525. [PMID: 33015469 PMCID: PMC7528315 DOI: 10.1021/acsomega.0c02992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 08/31/2020] [Indexed: 06/11/2023]
Abstract
In this work, we have reported the electronic structure, spin state, and optical properties of a new class of transition-metal (TM) dinuclear molecules (TM = Cr, Mn, Fe, Co, and Ni). The stability of these molecules has been analyzed from the vibration spectra obtained by using density functional theory (DFT) calculations. The ground-state spin configuration of the tetra-coordinated TM atom in each molecule has been predicted from the relative total energy differences in different spin states of the molecule. The DFT + U method has been used to investigate the precise ground-state spin configuration of each molecule. We further performed time-dependent DFT calculations to study the optical properties of these molecules. The planar geometric structure remains intact in most of the cases; hence, these molecules are expected to be well adsorbed and self-assembled on metal substrates. In addition, the optical characterization of these molecules indicates that the absorption spectra have a large peak in the blue-light wavelength range; therefore, it could be suitable for advanced optoelectronic device applications. Our work promotes further computational and experimental studies on TM dinuclear molecules in the field of molecular spintronics and optoelectronics.
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Volkova YM, Makarov AY, Pritchina EA, Gritsan NP, Zibarev AV. Herz radicals: chemistry and materials science. MENDELEEV COMMUNICATIONS 2020. [DOI: 10.1016/j.mencom.2020.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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9
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Tse JS. A chemical perspective on high pressure crystal structures and properties. Natl Sci Rev 2020; 7:149-169. [PMID: 34692029 PMCID: PMC8289026 DOI: 10.1093/nsr/nwz144] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 07/25/2019] [Accepted: 08/20/2019] [Indexed: 11/13/2022] Open
Abstract
The general availability of third generation synchrotron sources has ushered in a new era of high pressure research. The crystal structure of materials under compression can now be determined by X-ray diffraction using powder samples and, more recently, from multi-nano single crystal diffraction. Concurrently, these experimental advancements are accompanied by a rapid increase in computational capacity and capability, enabling the application of sophisticated quantum calculations to explore a variety of material properties. One of the early surprises is the finding that simple metallic elements do not conform to the general expectation of adopting 3D close-pack structures at high pressure. Instead, many novel open structures have been identified with no known analogues at ambient pressure. The occurrence of these structural types appears to be random with no rules governing their formation. The adoption of an open structure at high pressure suggested the presence of directional bonds. Therefore, a localized atomic hybrid orbital description of the chemical bonding may be appropriate. Here, the theoretical foundation and experimental evidence supporting this approach to the elucidation of the high pressure crystal structures of group I and II elements and polyhydrides are reviewed. It is desirable and advantageous to extend and apply established chemical principles to the study of the chemistry and chemical bonding of materials at high pressure.
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Affiliation(s)
- John S Tse
- Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada
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Mailman A, Robertson CM, Winter SM, Dube PA, Oakley RT. The Importance of Electronic Dimensionality in Multiorbital Radical Conductors. Inorg Chem 2019; 58:6495-6506. [PMID: 31021620 DOI: 10.1021/acs.inorgchem.9b00691] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The exceptional performance of oxobenzene-bridged bis-1,2,3-dithiazolyls 6 as single-component neutral radical conductors arises from the presence of a low-lying π-lowest unoccupied molecular orbital, which reduces the potential barrier to charge transport and increases the kinetic stabilization energy of the metallic state. As part of ongoing efforts to modify the solid-state structures and transport properties of these so-called multiorbital materials, we report the preparation and characterization of the acetoxy, methoxy, and thiomethyl derivatives 6 (R = OAc, OMe, SMe). The crystal structures are based on ribbonlike arrays of radicals laced together by S···N' and S···O' secondary bonding interactions. The steric and electronic effects of the exocyclic ligands varies, affording one-dimensional (1D) π-stacked radicals for R = OAc, 1D cofacial dimer π-stacks for R = SMe, and a pseudo two-dimensional (2D) brick-wall arrangement for R = OMe. Variable-temperature magnetic and conductivity measurements reveal strong antiferromagnetic interactions and Mott insulating behavior for the two radical-based structures (R = OAc, OMe), with lower room-temperature conductivities (σRT ≈ 1 × 10-4 and ∼1 × 10-3 S cm-1, respectively) and higher thermal activation energies ( Eact = 0.24 and 0.21 eV, respectively) than found for the ideal 2D brick-wall structure of 6 (R = F), where σRT ≈ 1 × 10-2 S cm-1 and Eact = 0.10 eV. The performance of R = OMe, OAc relative to that of R = F, is consistent with the results of density functional theory band electronic structure calculations, which indicate a lower kinetic stabilization energy of the putative metallic state arising from their reduced electronic dimensionality.
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Affiliation(s)
- Aaron Mailman
- Department of Chemistry , University of Jyväskylä , P.O. Box 35, Jyväskylä , Finland.,Department of Chemistry , University of Waterloo , Waterloo , Ontario N2L 3G1 , Canada
| | - Craig M Robertson
- Department of Chemistry , University of Liverpool , Liverpool L69 7ZD , United Kingdom
| | - Stephen M Winter
- Institut für Theoretische Physik , Goethe-Universität , Frankfurt am Main 60438 , Germany
| | - Paul A Dube
- Brockhouse Institute for Materials Research , McMaster University , Hamilton , Ontario L8S 4M1 , Canada
| | - Richard T Oakley
- Department of Chemistry , University of Waterloo , Waterloo , Ontario N2L 3G1 , Canada
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11
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Yong W, Lekin K, Bauer RPC, Tse JS, Desgreniers S, Secco RA, Hirao N, Oakley RT. Pancakes under Pressure: A Case Study on Isostructural Dithia- and Diselenadiazolyl Radical Dimers. Inorg Chem 2019; 58:3550-3557. [PMID: 30785745 DOI: 10.1021/acs.inorgchem.9b00142] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The isostructural dimers of the 1,4-phenylene-bridged bis-1,2,3,5-dithia- and bis-1,2,3,5-diselenadiazolyl diradicals 1,4-S/Se are small band gap semiconductors. The response of their molecular and solid state electronic structures to pressure has been explored over the range 0-10 GPa. The crystal structures, which consist of cofacially aligned (pancake) π-dimers packed into herringbone arrays, experience a continuous, near-isotropic compression. While the intramolecular covalent E-E (E = S/Se) bonds remain relatively unchanged with pressurization, the intradimer E···E separations are significantly shortened. Molecular and band electronic structure calculations using density functional theory methods indicate that compression of the π-dimers leads to a widening of the gap Δ E between the highest occupied and lowest unoccupied molecular orbitals of the dimer, an effect that offsets the expected decrease in the valence-to-conduction band gap Eg occasioned by pressure-induced spreading of the valence and conduction bands. Consistent with the predicted consequences of this competition between intra- and interdimer interactions, variable temperature high pressure conductivity measurements reveal at best an order-of-magnitude increase in conductivity with pressure for the two compounds over the pressure range 0-10 GPa. While a small reduction in the thermal activation energy Eact with increasing pressure is observed, extrapolation of the rate of decrease suggests a projected onset of metallization ( Eact ≈ 0) in excess of 20 GPa.
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Affiliation(s)
- Wenjun Yong
- Department of Earth Sciences , University of Western Ontario , London , Ontario N6A 5B7 , Canada
| | - Kristina Lekin
- Department of Chemistry , University of Waterloo , Waterloo , Ontario N2L 3G1 , Canada
| | - Robert P C Bauer
- Department of Physics , University of Saskatchewan , Saskatoon , Saskatchewan S7N 5E2 , Canada
| | - John S Tse
- Department of Physics , University of Saskatchewan , Saskatoon , Saskatchewan S7N 5E2 , Canada
| | - Serge Desgreniers
- Department of Physics , University of Ottawa , Ottawa , Ontario K1N 6N5 , Canada
| | - Richard A Secco
- Department of Earth Sciences , University of Western Ontario , London , Ontario N6A 5B7 , Canada
| | - Naohisa Hirao
- Materials Science Division , Japan Synchrotron Radiation Research Institute , SPring-8, Sayo , Hyogo 679-5198 , Japan
| | - Richard T Oakley
- Department of Chemistry , University of Waterloo , Waterloo , Ontario N2L 3G1 , Canada
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12
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Lee LM, Corless V, Luu H, He A, Jenkins H, Britten JF, Adam Pani F, Vargas-Baca I. Synthetic and structural investigations of bis(N-alkyl-benzoselenadiazolium) cations. Dalton Trans 2019; 48:12541-12548. [DOI: 10.1039/c9dt02311a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A variety of supramolecular structures is formed by selenadiazolium cations linked by hydrocarbon bridges.
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Affiliation(s)
- Lucia Myongwon Lee
- McMaster University
- Department of Chemistry and Chemical Biology
- Hamilton
- Canada L8S 4 M1
| | - Victoria Corless
- McMaster University
- Department of Chemistry and Chemical Biology
- Hamilton
- Canada L8S 4 M1
| | - Helen Luu
- McMaster University
- Department of Chemistry and Chemical Biology
- Hamilton
- Canada L8S 4 M1
| | - Allan He
- McMaster University
- Department of Chemistry and Chemical Biology
- Hamilton
- Canada L8S 4 M1
| | - Hilary Jenkins
- McMaster University
- Department of Chemistry and Chemical Biology
- Hamilton
- Canada L8S 4 M1
| | - James F. Britten
- McMaster University
- Department of Chemistry and Chemical Biology
- Hamilton
- Canada L8S 4 M1
| | - Faisal Adam Pani
- McMaster University
- Department of Chemistry and Chemical Biology
- Hamilton
- Canada L8S 4 M1
| | - Ignacio Vargas-Baca
- McMaster University
- Department of Chemistry and Chemical Biology
- Hamilton
- Canada L8S 4 M1
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Rakitin OA, Zibarev AV. Synthesis and Applications of 5‐Membered Chalcogen‐Nitrogen π‐Heterocycles with Three Heteroatoms. ASIAN J ORG CHEM 2018. [DOI: 10.1002/ajoc.201800536] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Oleg A. Rakitin
- N. D. Zelinsky Institute of Organic ChemistryRussian Academy of Sciences 119991 Moscow Russia
- Nanotechnology Education and Research CenterSouth Ural State University 454080 Chelyabinsk Russia
| | - Andrey V. Zibarev
- N. N. Vorozhtsov Institute of Organic ChemistrySiberian Branch of Russian Academy of Sciences 630090 Novosibirsk Russia
- Department of ChemistryNational Research University – Tomsk State University 634050 Tomsk Russia
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Taponen AI, Wong JWL, Lekin K, Assoud A, Robertson CM, Lahtinen M, Clérac R, Tuononen HM, Mailman A, Oakley RT. Non-Innocent Base Properties of 3- and 4-Pyridyl-dithia- and Diselenadiazolyl Radicals: The Effect of N-Methylation. Inorg Chem 2018; 57:13901-13911. [PMID: 30351085 DOI: 10.1021/acs.inorgchem.8b02416] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Anni I. Taponen
- Department of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä, Finland
| | - Joanne W. L. Wong
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Kristina Lekin
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Abdeljalil Assoud
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Craig M. Robertson
- Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD, United Kingdom
| | - Manu Lahtinen
- Department of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä, Finland
| | - Rodolphe Clérac
- Centre National de la Recherche Scientifique, CNRS, CRPP, UMR 5031, 33600 Pessac, France
- Université de Bordeaux, CRPP, UPR 5031, 33600 Pessac, France
| | - Heikki M. Tuononen
- Department of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä, Finland
| | - Aaron Mailman
- Department of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä, Finland
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Richard T. Oakley
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
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