1
|
Kubas A. How the Donor/Acceptor Spin States Affect the Electronic Couplings in Molecular Charge-Transfer Processes? J Chem Theory Comput 2021; 17:2917-2927. [PMID: 33830757 PMCID: PMC8154369 DOI: 10.1021/acs.jctc.1c00126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
The electronic coupling
matrix element HAB is an essential ingredient
of most electron-transfer theories. HAB depends on the overlap between donor and
acceptor wave functions and is affected by the involved states’
spin. We classify the spin-state effects into three categories: orbital
occupation, spin-dependent electron density, and density delocalization.
The orbital occupancy reflects the diverse chemical nature and reactivity
of the spin states of interest. The effect of spin-dependent density
is related to a more compact electron density cloud at lower spin
states due to decreased exchange interactions between electrons. Density
delocalization is strongly connected with the covalency concept that
increases the spatial extent of the diabatic state’s electron
density in specific directions. We illustrate these effects with high-level ab initio calculations on model direct donor–acceptor
systems relevant to metal oxide materials and biological electron
transfer. Obtained results can be used to benchmark existing methods
for HAB calculations in complicated cases
such as spin-crossover materials or antiferromagnetically coupled
systems.
Collapse
Affiliation(s)
- A Kubas
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| |
Collapse
|
2
|
Kumar KS, Ruben M. Sublimable Spin-Crossover Complexes: From Spin-State Switching to Molecular Devices. Angew Chem Int Ed Engl 2021; 60:7502-7521. [PMID: 31769131 PMCID: PMC8048919 DOI: 10.1002/anie.201911256] [Citation(s) in RCA: 122] [Impact Index Per Article: 40.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Indexed: 11/10/2022]
Abstract
Spin-crossover (SCO) active transition metal complexes are an important class of switchable molecular materials due to their bistable spin-state switching characteristics at or around room temperature. Vacuum-sublimable SCO complexes are a subclass of SCO complexes suitable for fabricating ultraclean spin-switchable films desirable for applications, especially in molecular electronics/spintronics. Consequently, on-surface SCO of thin-films of sublimable SCO complexes have been studied employing spectroscopy and microscopy techniques, and results of fundamental and technological importance have been obtained. This Review provides complete coverage of advances made in the field of vacuum-sublimable SCO complexes: progress made in the design and synthesis of sublimable functional SCO complexes, on-surface SCO of molecular and multilayer thick films, and various molecular and thin-film device architectures based on the sublimable SCO complexes.
Collapse
Affiliation(s)
- Kuppusamy Senthil Kumar
- Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS)CNRS-Université de Strasbourg23, rue du Loess, BP 4367034Strasbourg cedex 2France
| | - Mario Ruben
- Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS)CNRS-Université de Strasbourg23, rue du Loess, BP 4367034Strasbourg cedex 2France
- Institute of NanotechnologyKarlsruhe Institute of Technology (KIT)Hermann-von-Helmholtz-Platz 176344Eggenstein-LeopoldshafenGermany
- Institute of Quantum Materials and -TechnologyKarlsruhe Institute of Technology (KIT)Hermann-von-Helmholtz-Platz 176344Eggenstein-LeopoldshafenGermany
| |
Collapse
|
3
|
Dixon IM, Rat S, Sournia-Saquet A, Molnár G, Salmon L, Bousseksou A. On the Spin-State Dependence of Redox Potentials of Spin Crossover Complexes. Inorg Chem 2020; 59:18402-18406. [PMID: 33284611 DOI: 10.1021/acs.inorgchem.0c03043] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Resistance switching properties of nanoscale junctions of spin crossover molecules have received recently much interest. In many cases, this property has been traced back to the variation of molecular orbital energies upon spin transition. However, one can also expect a substantial reorganization of the molecular structure due to charge localization, which calls for a better understanding of the relationship between the redox potential and the spin state of the molecule. To investigate this issue, we carried out a detailed density functional theory and variable temperature cyclic voltammetry investigation of the benchmark compound [Fe(HB(1,2,4-triazol-1-yl)3)2] in solution. We show that, for a correct thermodynamical picture, it is necessary to take into account the charge transfer-induced electronic and structural reorganization as well as spin equilibria in the oxidized and reduced species.
Collapse
Affiliation(s)
- Isabelle M Dixon
- Laboratoire de Chimie et Physique Quantiques, UMR 5626 CNRS/Université Toulouse 3-Paul Sabatier, Université de Toulouse, 118 route de Narbonne, 31062 Toulouse, France
| | - Sylvain Rat
- Laboratoire de Chimie de Coordination, UPR 8241, CNRS and Université de Toulouse, UPS, INP, 205 route de Narbonne, 31077 Toulouse, France
| | - Alix Sournia-Saquet
- Laboratoire de Chimie de Coordination, UPR 8241, CNRS and Université de Toulouse, UPS, INP, 205 route de Narbonne, 31077 Toulouse, France
| | - Gábor Molnár
- Laboratoire de Chimie de Coordination, UPR 8241, CNRS and Université de Toulouse, UPS, INP, 205 route de Narbonne, 31077 Toulouse, France
| | - Lionel Salmon
- Laboratoire de Chimie de Coordination, UPR 8241, CNRS and Université de Toulouse, UPS, INP, 205 route de Narbonne, 31077 Toulouse, France
| | - Azzedine Bousseksou
- Laboratoire de Chimie de Coordination, UPR 8241, CNRS and Université de Toulouse, UPS, INP, 205 route de Narbonne, 31077 Toulouse, France
| |
Collapse
|
4
|
Kumar KS, Ruben M. Sublimierbare Spin‐Crossover‐Komplexe: Vom Schalten des Spinzustands zu molekularen Bauelementen. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201911256] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Kuppusamy Senthil Kumar
- Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS) CNRS-Université de Strasbourg 23, rue du Loess, BP 43 67034 Strasbourg cedex 2 Frankreich
| | - Mario Ruben
- Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS) CNRS-Université de Strasbourg 23, rue du Loess, BP 43 67034 Strasbourg cedex 2 Frankreich
- Institut für Nanotechnologie Karlsruher Institut für Technologie (KIT) Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Deutschland
- Institut für Quantenmaterialien und -technologien Karlsruher Institut für Technologie (KIT) Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Deutschland
| |
Collapse
|
5
|
Jia L, Wang C, Zhang Y, Yang L, Yan Y. Efficient Spin Selectivity in Self-Assembled Superhelical Conducting Polymer Microfibers. ACS NANO 2020; 14:6607-6615. [PMID: 32422046 DOI: 10.1021/acsnano.9b07681] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Chiral materials, natural or synthetic, have been widely studied since Pasteur's separation of enantiomers over a century ago. The connection between electron transmission and chirality was, however, established recently where one spin was preferably selected by the chiral molecules, displaying a typical chirality-induced spin selectivity (CISS) effect. Currently, this CISS effect was mainly demonstrated in the molecular-scale devices. Herein, we explored this effect in a microscale device where an efficient spin selectivity was found in the self-assembled superhelical conducting polyaniline (PANI) microfibers. A spin-selective efficiency up to 80% (not magnetoresistance) was achieved when spins traversed the ca. 2-6 μm-long helical channels at room temperature. Importantly, the long-range ordering of chiral PANI molecules is crucial to observe this efficient spin selectivity, whereas no selective transmission was found in the "amorphous" chiral PANIs. This efficient spin selectivity was subsequently rationalized by using an extended Su-Schrieffer-Heeger model where the Rashba spin-orbit coupling was considered. We expect these results could inspire the research of organic spintronics by using molecularly ordered, self-assembled, and chiral π-conjugated materials.
Collapse
Affiliation(s)
- Lei Jia
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
- School of Advanced Materials and Nanotechnology, Xidian University, Xi'an 710126, China
| | - Chenchen Wang
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuchun Zhang
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
| | - Liu Yang
- School of Physics and Electronic Engineering, Linyi University, Linyi 276005, China
| | - Yong Yan
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
6
|
Zhang Y. Driving spin transition at interface: Role of adsorption configurations. J Chem Phys 2018; 148:044706. [PMID: 29390826 DOI: 10.1063/1.5007739] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
A clear insight into the electrical manipulation of molecular spins at interface is crucial to the design of molecule-based spintronic devices. Here we report on the electrically driven spin transition in manganocene physisorbed on a metallic surface in two different adsorption configurations predicted by ab initio techniques, including a Hubbard-U correction at the manganese site and accounting for the long-range van der Waals interactions. We show that the application of an electric field at the interface induces a high-spin to low-spin transition in the flat-lying manganocene, while it could hardly alter the high-spin ground state of the standing-up molecule. This phenomenon cannot be explained by either the molecule-metal charge transfer or the local electron correlation effects. We demonstrate a linear dependence of the intra-molecular spin-state splitting on the energy difference between crystal-field splitting and on-site Coulomb repulsion. After considering the molecule-surface binding energy shifts upon spin transition, we reproduce the obtained spin-state energetics. We find that the configuration-dependent responses of the spin-transition originate from the binding energy shifts instead of the variation of the local ligand field. Through these analyses, we obtain an intuitive understanding of the effects of molecule-surface contact on spin-crossover under electrical bias.
Collapse
Affiliation(s)
- Yachao Zhang
- Guizhou Provincial Key Laboratory of Computational Nano-Material Science, Guizhou Education University, Guiyang 550018, China
| |
Collapse
|
7
|
Karan S, García C, Karolak M, Jacob D, Lorente N, Berndt R. Spin Control Induced by Molecular Charging in a Transport Junction. NANO LETTERS 2018; 18:88-93. [PMID: 29232947 DOI: 10.1021/acs.nanolett.7b03411] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The ability of molecules to maintain magnetic multistability in nanoscale-junctions will determine their role in downsizing spintronic devices. While spin-injection from ferromagnetic leads gives rise to magnetoresistance in metallic nanocontacts, nonmagnetic leads probing the magnetic states of the junction itself have been considered as an alternative. Extending this experimental approach to molecular junctions, which are sensitive to chemical parameters, we demonstrate that the electron affinity of a molecule decisively influences its spin transport. We use a scanning tunneling microscope to trap a meso-substituted iron porphyrin, putting the iron center in an environment that provides control of its charge and spin states. A large electron affinity of peripheral ligands is shown to enable switching of the molecular S = 1 ground state found at low electron density to S = 1/2 at high density, while lower affinity keeps the molecule inactive to spin-state transition. These results pave the way for spin control using chemical design and electrical means.
Collapse
Affiliation(s)
- Sujoy Karan
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel , 24098 Kiel, Germany
- Institute of Experimental and Applied Physics, University of Regensburg , 93053 Regensburg, Germany
| | - Carlos García
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, 20018 Donostia-San Sebastián, Spain
| | - Michael Karolak
- Institut für Theoretische Physik und Astrophysik, Universität Würzburg , Am Hubland, 97074 Würzburg, Germany
| | - David Jacob
- Departamento de Física de Materiales, Universidad del País Vasco, UPV/EHU , Av. Tolosa 72, 20018 San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, Maria Diaz de Haro 3, 48013 Bilbao, Spain
| | - Nicolás Lorente
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, 20018 Donostia-San Sebastián, Spain
- Centro de Física de Materiales CFM/MPC, CSIC-UPV/EHU , Paseo Manuel de Lardizabal 5, 20018 Donostia-San Sebastián, Spain
| | - Richard Berndt
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel , 24098 Kiel, Germany
| |
Collapse
|