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Lathion T, Deorukhkar N, Egger C, Nozary H, Piguet C. Molecular Fe(II)-Ln(III) dyads for luminescence reading of spin-state equilibria at the molecular level. Dalton Trans 2024. [PMID: 39311462 PMCID: PMC11418352 DOI: 10.1039/d4dt01868k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2024] [Accepted: 09/13/2024] [Indexed: 09/26/2024]
Abstract
Due to the primogenic effect, the valence shells of divalent iron Fe(II) ([Ar]3d6) and trivalent lanthanides Ln(III) ([Xe]4fn) are compact enough to induce spin-state equilibrium for the 3d-block metal and atom-like luminescence for the 4f-block partner in Fe(II)-Ln(III) dyads. In the specific case of homoleptic pseudo-octahedral [Fe(II)N6] units, programming spin crossover (SCO) around room temperature at normal pressure requires the design of unsymmetrical didentate five-membered ring chelating N∩N' ligands, in which a five-membered (benz)imidazole heterocycle (N) is connected to a six-membered pyrimidine heterocycle (N'). Benefiting from the trans influence, the facial isomer fac-[Fe(II)(N∩N')3]2+ is suitable for inducing SCO properties at room temperature in solution. Its connection to luminescent [LnN6O3] chromophores working as non-covalent podates in the triple-stranded [Fe(II)Ln(L10)3]5+ helicates (Ln = Nd, Eu) controls the facial arrangement around Fe(II). The iron-based SCO behaviour of the 3d-4f complex mirrors that programmed in the mononuclear scaffold. Because of the different electronic structures of high-spin and low-spin [Fe(II)N6] units, their associated absorption spectra are different and modulate the luminescence of the appended lanthanide luminophore via intramolecular intermetallic energy transfers. It thus becomes possible to detect the spin state of the Fe(II) center, encoded by an external perturbation (i.e. writing), by lanthanide light emission (i.e. reading) in a single molecule and without disturbance. Shifting from visible emission (Ln = Eu) to the near-infrared domain (Ln = Nd) further transforms a wavy emitted signal intensity into a linear one, a protocol highly desirable for future applications in data storage and thermometry.
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Affiliation(s)
- Timothée Lathion
- Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai E. Ansermet, CH-1211 Geneva 4, Switzerland.
- CNRS - CBM Rue Charles Sadron CS 80054, 45071 Orleans, Cedex 2, France
| | - Neel Deorukhkar
- Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai E. Ansermet, CH-1211 Geneva 4, Switzerland.
| | - Charlotte Egger
- Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai E. Ansermet, CH-1211 Geneva 4, Switzerland.
| | - Homayoun Nozary
- Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai E. Ansermet, CH-1211 Geneva 4, Switzerland.
| | - Claude Piguet
- Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai E. Ansermet, CH-1211 Geneva 4, Switzerland.
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2
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Deorukhkar N, Egger C, Rosspeintner A, Piguet C. Unravelling Kinetics of Intramolecular Nd III → Fe II Energy Transfer in Spin Crossover Single Molecules: Dotting the i's and Crossing the t's. J Am Chem Soc 2024; 146:19386-19396. [PMID: 38953864 DOI: 10.1021/jacs.4c05546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
Compared with the ripple of visible EuIII-based emission intensity induced by appended [FeIIN6] spin crossover (SCO) units, as detected in the triple-stranded [EuFe(L1)3]5+ helicate, the lanthanide-based luminescent detection of FeII spin-state equilibria could be improved significantly if the luminophore emission is shifted toward the near-infrared (NIR) domain. Replacing EuIII with NdIII in [NdFe(L1)3]5+ (i) maintains the favorable SCO properties in acetonitrile [critical temperature T1/2 = 322(2) K], (ii) saturates nonradiative vibrational relaxation processes in the 233-333 K range, and (iii) boosts the crucial intramolecular NdIII → FeII energy transfer rate processes, which are sensitive to the spin state of the FeII metallic center. Consequently, the steady-state NIR Nd(4F3/2 → 4IJ) emission of the luminophore is amplified and linearly correlated with the low-spin-[FeIIN6] and high-spin-[FeIIN6] mole fractions controlled by the SCO equilibrium. This paves the way for a straightforward and direct NIR luminescent reading/sensing of the FeII spin state in single molecules.
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Affiliation(s)
- Neel Deorukhkar
- Department of Inorganic and Analytical Chemistry, University of Geneva, 30 Quai E. Ansermet, CH-1211 Geneva 4, Switzerland
| | - Charlotte Egger
- Department of Inorganic and Analytical Chemistry, University of Geneva, 30 Quai E. Ansermet, CH-1211 Geneva 4, Switzerland
| | - Arnulf Rosspeintner
- Department of Physical Chemistry, University of Geneva, 30 Quai E. Ansermet, CH-1211 Geneva 4, Switzerland
| | - Claude Piguet
- Department of Inorganic and Analytical Chemistry, University of Geneva, 30 Quai E. Ansermet, CH-1211 Geneva 4, Switzerland
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3
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Bento MA, Gomes T, Martins FF, Gil A, Ferreira LP, Barroso S, Gomes CSB, Garcia Y, Martinho PN. The role of intermolecular interactions in [Fe(X-salEen) 2]ClO 4 spin crossover complexes. Dalton Trans 2024; 53:8791-8802. [PMID: 38713065 DOI: 10.1039/d4dt00400k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Two new spin crossover (SCO) Fe(III) compounds were prepared, their structures were analysed and their magnetic properties were investigated. An exhaustive analysis of the effects of halogen substitution and aromatic ring functionalisation on the magnetic properties of non-solvated Fe(III) perchlorate complexes has been performed. Through comparative analysis, different magnetic profiles were found for the compounds studied, namely F (1), Cl (2), H (3), Br (4a, 4b), and I (5). Using tools like Hirshfeld analysis, the study revealed patterns in octahedral distortions and deviations from the ideal octahedral geometry. The SCO phenomenon as the conducting wire in this study, emphasises the influence of intermolecular interactions on the low spin (LS) to high spin (HS) transitions in these halogen-substituted complexes. The prevalence of H⋯H contributions has been demonstrated, albeit being the weakest and an inverse strength relationship in H⋯X interactions ranging from F to I. The findings not only interpret the intricate balance between halogen substitution, functionalisation, and intermolecular interactions in modulating magnetic properties but also direct future works in designing similar molecular systems.
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Affiliation(s)
- Marcos A Bento
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal.
| | - Tiago Gomes
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal.
| | - Frederico F Martins
- BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Adrià Gil
- BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
- Departament de Química, Física i Ciències Ambientals i del Sòl, ETSEA - Escola Tècnica Superior d'Enginyeria Agrària, Universitat de Lleida, Av. de l'alcalde Rovira Roure, 191, E25198, Lleida, Catalunya, Spain
| | - Liliana P Ferreira
- Department of Physics, University of Coimbra, 3004-516 Coimbra, Portugal
- Centro de Física Teórica e Computacional, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, Edifício C8, 1749-016 Lisboa, Portugal
| | - Sónia Barroso
- UCIBIO, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
- i4HB, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - Clara S B Gomes
- LAQV-REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal
| | - Yann Garcia
- Institute of Condensed Matter and Nanosciences, Molecular Chemistry, Materials and Catalysis (IMCN/MOST), Université Catholique de Louvain, Place L. Pasteur 1, 1348 Louvain-la-Neuve, Belgium
| | - Paulo N Martinho
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal.
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4
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Ishii T, Ogasawara K, Sakane G. Exploring spin states and ligand field splitting in metal complexes: a theoretical analysis of spin-orbital interactions and magnetic properties. Dalton Trans 2024; 53:7175-7189. [PMID: 38573393 DOI: 10.1039/d4dt00329b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2024]
Abstract
Metal complexes are pivotal in diverse fields due to their wide array of functionalities, including magnetism, conductivity, and photoresponsiveness. These functionalities are intricately linked to the phenomenon of ligand field splitting, yet controlling the magnitude of this splitting within metal complexes presents a significant challenge. This study aims to address this challenge by developing a novel 2D spectrochemical series, integrating two critical parameters: metal ions and ligands. Employing the DV-Xα molecular orbital method, we directly calculated ligand field splitting width, enabling a detailed assessment of energy splitting trends. Our results reveal that the magnitude of ligand field splitting, encompassing 17 metal types and 29 ligand types, can be precisely controlled. This represents a significant advancement over traditional spectrochemical series, such as those proposed by R. Tsuchida, which predominantly focus on either ligands or metals in isolation. Additionally, our study extends to the calculation of spin states in these metal complexes, contributing valuable insights for the development of magnetic materials. We demonstrate that the relative ligand field splitting and spin polarization can be used to predict spin states, offering a new perspective in material design and functionality. These findings not only enhance our understanding of ligand field splitting in metal complexes but also provide a comprehensive framework for predicting their electronic and magnetic properties, paving the way for innovative applications in material science and coordination chemistry.
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Affiliation(s)
- Tomohiko Ishii
- Faculty of Engineering and Design, Kagawa University, Kagawa 761-0396, Japan.
| | - Kazuyoshi Ogasawara
- Department of Chemistry, Faculty of Science, Kwansei Gakuin University, Hyogo 669-1330, Japan
| | - Genta Sakane
- Center for Fundamental Education, Institute for the Advancement of Higher Education, Okayama University of Science, Okayama 700-0005, Japan
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5
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Deorukhkar N, Egger C, Guénée L, Besnard C, Piguet C. Detecting Fe(II) Spin-Crossover by Modulation of Appended Eu(III) Luminescence in a Single Molecule. J Am Chem Soc 2024; 146:308-318. [PMID: 37877700 DOI: 10.1021/jacs.3c09017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2023]
Abstract
Multifunctionality in spin-crossover (SCO) devices is limited to macroscopic or nanoscopic materials because of the need for long-range effects for inducing favorable cooperativity, efficient energy migration processes, and detectable magnetization transfer. The difficult reproducibility, control, and rational design of doped materials offer some place to SCO processes, modulating the optical properties of neighboring luminescent probes in single molecules. We report here on the combination of a [FeN6] chromophore, the SCO temperature and absorption spectra of which have been tuned to induce unprecedented room-temperature modulation of Eu(III)-based line-like luminescence in the molecular triple-helical [EuFe(L2)3]5+ complex in solution.
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Affiliation(s)
- Neel Deorukhkar
- Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai E. Ansermet, CH-1211 Geneva 4, Switzerland
| | - Charlotte Egger
- Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai E. Ansermet, CH-1211 Geneva 4, Switzerland
| | - Laure Guénée
- Laboratory of Crystallography, University of Geneva, 24 quai E. Ansermet. CH-1211 Geneva 4, Switzerland
| | - Céline Besnard
- Laboratory of Crystallography, University of Geneva, 24 quai E. Ansermet. CH-1211 Geneva 4, Switzerland
| | - Claude Piguet
- Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai E. Ansermet, CH-1211 Geneva 4, Switzerland
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6
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Orellana-Silla A, Meneses-Sánchez M, Turo-Cortés R, Muñoz MC, Bartual-Murgui C, Real JA. Symmetry Breaking and Cooperative Spin Crossover in a Hofmann-Type Coordination Polymer Based on Negatively Charged {Fe II(μ 2-[M II(CN) 4]) 2} n2n- Layers (M II = Pd, Pt). Inorg Chem 2023; 62:12783-12792. [PMID: 37526289 PMCID: PMC10428219 DOI: 10.1021/acs.inorgchem.3c01332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Indexed: 08/02/2023]
Abstract
We report herein the synthesis and characterization of two unprecedented isomorphous spin-crossover two-dimensional coordination polymers of the Hofmann-type formulated {FeII(Hdpyan)2(μ2-[MII(CN)4])2}, with MII = Pd, Pt and Hdpyan is the in situ partially protonated form of 2,5-(dipyridin-4-yl)aniline (dpyan). The FeII is axially coordinated by the pyridine ring attached to the 2-position of the aniline ring, while it is equatorially surrounded by four [MII(CN)4]2- planar groups acting as trans μ2-bidentate ligands defining layers, which stack parallel to each other. The other pyridine group of Hdpyan, being protonated, remains peripheral but involved in a strong [MII-C≡N···Hpy+] hydrogen bond between alternate layers. This provokes a nearly 90° rotation of the plane defined by the [MII(CN)4]2- groups, with respect to the average plane defined by the layers, forcing the observed uncommon bridging mode and the accumulation of negative charge around each FeII, which is compensated by the axial [Hdpyan]+ ligands. According to the magnetic and calorimetric data, both compounds undergo a strong cooperative spin transition featuring a 10-12 K wide hysteresis loop centered at 220 (Pt) and 211 K (Pd) accompanied by large entropy variations, 97.4 (Pt) and 102.9 (Pd) J/K mol. The breaking symmetry involving almost 90° rotation of one of the two coordinated pyridines together with the large unit-cell volume change per FeII (ca. 50 Å3), and subsequent release of significantly short interlayer contacts upon the low-spin → high-spin event, accounts for the strong cooperativity.
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Affiliation(s)
- Alejandro Orellana-Silla
- Departamento
de Química Inorgánica, Instituto de Ciencia Molecular
(ICMol), Universidad de Valencia, Paterna, 46980 Valencia, Spain
| | - Manuel Meneses-Sánchez
- Departamento
de Química Inorgánica, Instituto de Ciencia Molecular
(ICMol), Universidad de Valencia, Paterna, 46980 Valencia, Spain
| | - Rubén Turo-Cortés
- Departamento
de Química Inorgánica, Instituto de Ciencia Molecular
(ICMol), Universidad de Valencia, Paterna, 46980 Valencia, Spain
| | - M. Carmen Muñoz
- Departamento
de Fisica Aplicada, Universitat Politècnica
de València, Camino de Vera s/n, 46022 Valencia, Spain
| | - Carlos Bartual-Murgui
- Departamento
de Química Inorgánica, Instituto de Ciencia Molecular
(ICMol), Universidad de Valencia, Paterna, 46980 Valencia, Spain
| | - José Antonio Real
- Departamento
de Química Inorgánica, Instituto de Ciencia Molecular
(ICMol), Universidad de Valencia, Paterna, 46980 Valencia, Spain
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7
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Shakirova OG, Os'kina IA, Korotaev EV, Petrov SA, Kuratieva NV, Tikhonov AY, Lavrenova LG. Spin Crossover and Thermochromism in Iron(II) Complexes with 2,6-Bis(1 H-imidazol-2-yl)-4-methoxypyridine. Int J Mol Sci 2023; 24:9853. [PMID: 37373001 DOI: 10.3390/ijms24129853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 05/24/2023] [Accepted: 06/04/2023] [Indexed: 06/29/2023] Open
Abstract
New iron(II) complexes with 2,6-bis(1H-imidazol-2-yl)-4-methoxypyridine (L) of the composition [FeL2]An∙mH2O (A = SO42-, n = 1, m = 2 (I); A = ReO4-, n = 2, m = 1 (II); A = Br-, n = 2, m = 2 (III)) have been synthesized and investigated. To determine the coordination ability of the ligand, a single crystal of a copper(II) complex of the composition [CuLCl2] (IV) was obtained and studied by X-ray technique. Compounds I-III were studied using methods of X-ray phase analysis, electron (diffuse reflection spectra), infrared and Mössbauer spectroscopy, static magnetic susceptibility. The study of the µeff(T) dependence showed that the 1A1 ↔ 5T2 spin crossover manifests itself in the compounds. The spin crossover is accompanied by thermochromism: there is a distinct color change orange ↔ red-violet.
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Affiliation(s)
- Olga G Shakirova
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Department of Chemistry and Chemical Technologies, Faculty of Machinery and Chemical Technologies, Federal State Budget Institution of Higher Education, Komsomolsk-na-Amure State University, 681013 Komsomolsk-on-Amur, Russia
| | - Irina A Os'kina
- N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Evgeniy V Korotaev
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Sergey A Petrov
- Institute of Solid State Chemistry, Siberian Branch, Russian Academy of Sciences, 630128 Novosibirsk, Russia
| | - Natalia V Kuratieva
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Alexsei Ya Tikhonov
- N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Lyudmila G Lavrenova
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
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8
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Kilic MS, Brehme J, Pawlak J, Tran K, Bauer FW, Shiga T, Suzuki T, Nihei M, Sindelar RF, Renz F. Incorporation and Deposition of Spin Crossover Materials into and onto Electrospun Nanofibers. Polymers (Basel) 2023; 15:polym15102365. [PMID: 37242940 DOI: 10.3390/polym15102365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 05/16/2023] [Accepted: 05/17/2023] [Indexed: 05/28/2023] Open
Abstract
We synthesized iron(II)-triazole spin crossover compounds of the type [Fe(atrz)3]X2 and incorporated and deposited them on electrospun polymer nanofibers. For this, we used two separate electrospinning methods with the goal of obtaining polymer complex composites with intact switching properties. In view of possible applications, we chose iron(II)-triazole-complexes that are known to exhibit spin crossover close to ambient temperature. Therefore, we used the complexes [Fe(atrz)3]Cl2 and [Fe(atrz)3](2ns)2 (2ns = 2-Naphthalenesulfonate) and deposited those on fibers of polymethylmethacrylate (PMMA) and incorporated them into core-shell-like PMMA fiber structures. These core-shell structures showed to be inert to outer environmental influences, such as droplets of water, which we purposely cast on the fiber structure, and it did not rinse away the used complex. We analyzed both the complexes and the composites with IR-, UV/Vis, Mössbauer spectroscopy, SQUID magnetometry, as well as SEM and EDX imaging. The analysis via UV/Vis spectroscopy, Mössbauer spectroscopy, and temperature-dependent magnetic measurements with the SQUID magnetometer showed that the spin crossover properties were maintained and were not changed after the electrospinning processes.
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Affiliation(s)
- Maximilian Seydi Kilic
- Institute of inorganic Chemistry, Leibniz Universität Hannover, Callinstraße 7, 30167 Hannover, Germany
| | - Jules Brehme
- Institute of inorganic Chemistry, Leibniz Universität Hannover, Callinstraße 7, 30167 Hannover, Germany
- Faculty II, Hochschule Hannover, University of Applied Science an Arts, Ricklinger Stadtweg 120, 30459 Hannover, Germany
- Hannover School for Nanotechnology, Laboratorium für Nano-und Quantenengineering (LNQE), Leibniz Universität Hannover, Schneiderberg 39, 30167 Hannover, Germany
| | - Justus Pawlak
- Institute of inorganic Chemistry, Leibniz Universität Hannover, Callinstraße 7, 30167 Hannover, Germany
- Hannover School for Nanotechnology, Laboratorium für Nano-und Quantenengineering (LNQE), Leibniz Universität Hannover, Schneiderberg 39, 30167 Hannover, Germany
| | - Kevin Tran
- Institute of inorganic Chemistry, Leibniz Universität Hannover, Callinstraße 7, 30167 Hannover, Germany
- Hannover School for Nanotechnology, Laboratorium für Nano-und Quantenengineering (LNQE), Leibniz Universität Hannover, Schneiderberg 39, 30167 Hannover, Germany
| | - Friedrich Wilhelm Bauer
- Faculty II, Hochschule Hannover, University of Applied Science an Arts, Ricklinger Stadtweg 120, 30459 Hannover, Germany
| | - Takuya Shiga
- Graduate School of Pure and Applied Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba 305-8577, Ibaraki, Japan
| | - Taisei Suzuki
- Graduate School of Pure and Applied Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba 305-8577, Ibaraki, Japan
| | - Masayuki Nihei
- Graduate School of Pure and Applied Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba 305-8577, Ibaraki, Japan
| | - Ralf Franz Sindelar
- Faculty II, Hochschule Hannover, University of Applied Science an Arts, Ricklinger Stadtweg 120, 30459 Hannover, Germany
- Hannover School for Nanotechnology, Laboratorium für Nano-und Quantenengineering (LNQE), Leibniz Universität Hannover, Schneiderberg 39, 30167 Hannover, Germany
| | - Franz Renz
- Institute of inorganic Chemistry, Leibniz Universität Hannover, Callinstraße 7, 30167 Hannover, Germany
- Hannover School for Nanotechnology, Laboratorium für Nano-und Quantenengineering (LNQE), Leibniz Universität Hannover, Schneiderberg 39, 30167 Hannover, Germany
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Roseiro P, Yalouz S, Brook DJR, Ben Amor N, Robert V. Modifications of Tanabe-Sugano d6 Diagram Induced by Radical Ligand Field: Ab Initio Inspection of a Fe(II)-Verdazyl Molecular Complex. Inorg Chem 2023; 62:5737-5743. [PMID: 36971364 DOI: 10.1021/acs.inorgchem.3c00275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
Quantum entanglement between the spin states of a metal center and radical ligands is suggested in an iron(II) [Fe(dipyvd)2]2+ compound (dipyvd = 1-isopropyl-3,5-dipyridil-6-oxoverdazyl). Wave function ab initio (Difference Dedicated Configuration Interaction, DDCI) inspections were carried out to stress the versatility of local spin states. We named this phenomenon excited state spinmerism, in reference to our previous work (see Roseiro et al., ChemPhysChem 2022, e202200478) where we introduced the concept of spinmerism as an extension of mesomerism to spin degrees of freedom. The construction of localized molecular orbitals allows for a reading of the wave functions and projections onto the local spin states. The low-energy spectrum is well-depicted by a Heisenberg picture. A 60 cm-1 ferromagnetic interaction is calculated between the radical ligands with the Stotal = 0 and 1 states largely dominated by a local low-spin SFe = 0. In contrast, the higher-lying Stotal = 2 states are superpositions of the local SFe = 1 (17%, 62%) and SFe = 2 (72%, 21%) spin states. Such mixing extends the traditional picture of a high-field d6 Tanabe-Sugano diagram. Even in the absence of spin-orbit coupling, the avoided crossing between different local spin states is triggered by the field generated by radical ligands. This puzzling scenario emerges from versatile local spin states in compounds which extend the traditional views in molecular magnetism.
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High-Temperature Spin Crossover in Iron(II) Complexes with 2,6-Bis(1H-imidazol-2-yl)pyridine. Molecules 2022; 27:molecules27165093. [PMID: 36014332 PMCID: PMC9415506 DOI: 10.3390/molecules27165093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/04/2022] [Accepted: 08/05/2022] [Indexed: 11/17/2022] Open
Abstract
Novel iron(II) coordination compounds containing a ligand 2,6-bis(1H-imidazol-2-yl)pyridine (L), having such a composition as [FeL2]SO4·0.5H2O, [FeL2]Br2·H2O, [FeL2](ReO4)2, [FeL2]B10H10∙H2O, [FeL2]B12H12∙1.5H2O had been synthesized and studied using UV-Vis (diffuse reflectance), infrared, extended X-ray absorption fine structure (EXAFS), and Mössbauer spectroscopy methods, as well as X-ray diffraction and static magnetic susceptibility methods. The analysis of the μeff(T) dependence in the temperature range of 80–600 K have shown that all the obtained complexes exhibit a high-temperature spin crossover 1A1 ↔ 5T2.
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11
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Ivanova AD, Lavrenova LG, Korotaev EV, Trubina SV, Tikhonov AY, Kriventsov VV, Petrov SA, Zhizhin KY, Kuznetsov NT. Study of Spin-Crossover in Iron(II) Complexes with 2,6-Bis(4,5-Dimethyl-1H-Imidazol-2-yl)Pyridine and closo-Borate Anions. RUSS J INORG CHEM+ 2022. [DOI: 10.1134/s0036023622080174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Abstract
New iron(II) coordination compounds with 2,6-bis(4,5-dimethyl-1H-imidazol-2-yl)pyridine (L) and closo-borate(2–) anions [FeL2]B10H10⋅2H2O and [FeL2]B12H12⋅H2O have been synthesized. The compounds have been identified and studied by CHN analysis, electron spectroscopy (diffuse reflection spectroscopy), IR, Mössbauer, and EXAFS spectroscopies, X-ray powder diffraction, and static magnetic susceptibility. The structures of the coordination knots of complexes [FeL2]B10H10⋅2H2O and [FeL2]B12H12⋅H2O has been obtained by modeling the EXAFS spectra. The ligand is coordinated by the iron(II) ion in a tridentate-cyclic manner by two nitrogen atoms of imidazole cycles and a nitrogen atom of pyridine to form the FeN6 coordination knot. The study of the temperature dependence of the magnetic susceptibility in the range of 80–500 K has showed that the high-temperature spin-crossover 1А1 ↔ 5Т2 manifests itself in the obtained compounds.
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12
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Angulo-Cervera JE, Piedrahita-Bello M, Martin B, Alavi SE, Nicolazzi W, Salmon L, Molnár G, Bousseksou A. Thermal hysteresis of stress and strain in spin-crossover@polymer composites: towards a rational design of actuator devices. MATERIALS ADVANCES 2022; 3:5131-5137. [PMID: 35812835 PMCID: PMC9207597 DOI: 10.1039/d2ma00459c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 05/20/2022] [Indexed: 06/01/2023]
Abstract
Polymer composites of molecular spin crossover complexes have emerged as promising mechanical actuator materials, but their effective thermomechanical properties remain elusive. In this work, we investigated a series of iron(ii)-triazole@P(VDF-TrFE) particulate composites using a tensile testing stage with temperature control. From these measurements, we assessed the temperature dependence of the Young's modulus as well as the free deformation and blocking stress, associated with the thermally-induced spin transition. The results denote that the expansion of the particles at the spin transition is effectively transferred to the macroscopic composite material, providing ca. 1-3% axial strain for 25% particle load. This strain is in excess of the 'neat' particle strain, which we attribute to particle-matrix mechanical coupling. On the other hand, the blocking stress (∼1 MPa) appears reduced by the softening of the composite around the spin transition temperature.
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Affiliation(s)
| | | | - Baptiste Martin
- LCC, CNRS & University of Toulouse 205 route de Narbonne 31077 Toulouse France
| | - Seyed Ehsan Alavi
- LCC, CNRS & University of Toulouse 205 route de Narbonne 31077 Toulouse France
| | - William Nicolazzi
- LCC, CNRS & University of Toulouse 205 route de Narbonne 31077 Toulouse France
| | - Lionel Salmon
- LCC, CNRS & University of Toulouse 205 route de Narbonne 31077 Toulouse France
| | - Gábor Molnár
- LCC, CNRS & University of Toulouse 205 route de Narbonne 31077 Toulouse France
| | - Azzedine Bousseksou
- LCC, CNRS & University of Toulouse 205 route de Narbonne 31077 Toulouse France
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13
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Üngör Ö, Ozvat TM, Ni Z, Zadrozny JM. Record Chemical-Shift Temperature Sensitivity in a Series of Trinuclear Cobalt Complexes. J Am Chem Soc 2022; 144:9132-9137. [PMID: 35549174 DOI: 10.1021/jacs.2c03115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Designing spins that exhibit long-lived coherence and strong temperature sensitivity is central to designing effective molecular thermometers and a fundamental challenge in the chemistry/quantum-information space. Herein, we provide a new pathway to both properties in the same molecule by designing a nuclear spin, which possesses a robust spin coherence, to mimic the strong temperature sensitivity of an electronic spin. This design strategy is demonstrated in the group of trinuclear Co(III) spin-crossover compounds [(CpCo(OP(OR)2)3)2Co](SbCl6) where Cp = cyclopentadienyl and R = Me (1), Et (2), i-Pr (3), and t-Bu (4). Nuclear magnetic resonance analyses of the 59Co nuclear spins reveal 59Co chemical-shift temperature sensitivity (Δδ/ΔT) values that span from 101(1) ppm/°C in 1 to 149(1) ppm/°C in 2 and 150(2) ppm/°C in 4, where the latter two are record temperature sensitivities for any nuclear spin. Additionally, complexes 2 and 4 have T2* values of 74 and 78 μs in solution at ambient temperatures surpassing those from electron-spin-based complexes, which typically display long coherence times only at extremely low temperatures. Our results suggest that spin-crossover phenomena can enable electron-spin-like temperature sensitivities in nuclear spins while retaining robust coherence times at room temperature.
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Affiliation(s)
- Ökten Üngör
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Tyler M Ozvat
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Zhen Ni
- Department of Chemistry, Texas A&M University, 3255 TAMU, College Station, Texas 77843, United States
| | - Joseph M Zadrozny
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
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14
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Nadeem M, Cruddas J, Ruzzi G, Powell BJ. Toward High-Temperature Light-Induced Spin-State Trapping in Spin-Crossover Materials: The Interplay of Collective and Molecular Effects. J Am Chem Soc 2022; 144:9138-9148. [PMID: 35546521 DOI: 10.1021/jacs.2c03202] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Spin-crossover (SCO) materials display many fascinating behaviors including collective phase transitions and spin-state switching controlled by external stimuli, e.g., light and electrical currents. As single-molecule switches, they have been fêted for numerous practical applications, but these remain largely unrealized-partly because of the difficulty of switching these materials at high temperatures. We introduce a semiempirical microscopic model of SCO materials combining crystal field theory with elastic intermolecular interactions. For realistic parameters, this model reproduces the key experimental results including thermally induced phase transitions, light-induced spin-state trapping (LIESST), and reverse-LIESST. Notably, we reproduce and explain the experimentally observed relationship between the critical temperature of the thermal transition, T1/2, and the highest temperature for which the trapped state is stable, TLIESST, and explain why increasing the stiffness of the coordination sphere increases TLIESST. We propose strategies to design SCO materials with higher TLIESST: optimizing the spin-orbit coupling via heavier atoms (particularly in the inner coordination sphere) and minimizing the enthalpy difference between the high-spin (HS) and low-spin (LS) states. However, the most dramatic increases arise from increasing the cooperativity of the spin-state transition by increasing the rigidity of the crystal. Increased crystal rigidity can also stabilize the HS state to low temperatures on thermal cycling yet leave the LS state stable at high temperatures following, for example, reverse-LIESST. We show that such highly cooperative systems offer a realistic route to robust room-temperature switching, demonstrate this in silico, and discuss material design rationale to realize this.
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Affiliation(s)
- M Nadeem
- School of Mathematics and Physics, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Jace Cruddas
- School of Physical Sciences, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Gian Ruzzi
- School of Mathematics and Physics, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Benjamin J Powell
- School of Mathematics and Physics, The University of Queensland, Brisbane, Queensland 4072, Australia
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15
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Influence of Cooperative Interactions on the Spin Crossover Phenomenon in Iron(II) Complexes: A Review. THEOR EXP CHEM+ 2022. [DOI: 10.1007/s11237-022-09725-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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16
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Spin crossover in iron(II) complexes with new ligand 2,6-bis(4,5-dimethyl-1H-imidazole-2-yl)pyridine. Inorganica Chim Acta 2022. [DOI: 10.1016/j.ica.2021.120746] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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17
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Liu J, Abel M, Lin N. On-Surface Synthesis: A New Route Realizing Single-Layer Conjugated Metal-Organic Structures. J Phys Chem Lett 2022; 13:1356-1365. [PMID: 35112878 DOI: 10.1021/acs.jpclett.1c04134] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Recently, both experimental and theoretical advances have demonstrated that two-dimensional conjugated metal-organic frameworks (2D-cMOFs) exhibit interesting electronic and magnetic properties, such as high conductivity and ferromagnetism. Theoretical studies have predicted that exotic quantum states, including topological insulating states and superconductivity, emerge in some 2D-MOFs. The high design tunability of MOFs' structure and composition provides great opportunities to realize these structures. However, most conventional synthesis methods yield multilayer structures of the 2D-cMOFs, in which the predicted exotic quantum phases are often quenched because of interlayer interactions. It is highly desirable to synthesize single-layer cMOFs. On-surface synthesis represents a novel strategy toward this goal. In this Perspective, we discuss the recent developments in on-surface synthesis of 1D- and 2D-cMOFs.
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Affiliation(s)
- Jing Liu
- Division of Quantum State of Matter, Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - Mathieu Abel
- Aix Marseille Universite, CNRS, IM2NP, Marseille 13397, France
| | - Nian Lin
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
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18
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Moll J, Förster C, König A, Carrella LM, Wagner M, Panthöfer M, Möller A, Rentschler E, Heinze K. Panchromatic Absorption and Oxidation of an Iron(II) Spin Crossover Complex. Inorg Chem 2022; 61:1659-1671. [PMID: 35020386 DOI: 10.1021/acs.inorgchem.1c03511] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In order to expand and exploit the useful properties of d6-iron(II) and d5-iron(III) complexes in potential magnetic, photophysical, or magnetooptical applications, crucial ligand-controlled parameters are the ligand field strength in a given coordination mode and the availability of suitable metal and ligand frontier orbitals for charge-transfer processes. The push-pull ligand 2,6-diguanidylpyridine (dgpy) features low-energy π* orbitals at the pyridine site and strongly electron-donating guanidinyl donors combined with the ability to form six-membered chelate rings for optimal metal-ligand orbital overlap. The electronic ground states of the pseudo-octahedral d6- and d5-complexes mer-[Fe(dgpy)2]2+, cis-fac-[Fe(dgpy)2]2+, and mer-[Fe(dgpy)2]3+ as well as their charge-transfer (CT) and metal-centered (MC) excited states are probed by variable temperature UV/vis absorption, NMR, EPR, and Mössbauer spectroscopy, magnetic susceptibility measurements at variable temperature as well as quantum chemical calculations.
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Affiliation(s)
- Johannes Moll
- Department of Chemistry, Johannes Gutenberg University, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Christoph Förster
- Department of Chemistry, Johannes Gutenberg University, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Alexandra König
- Department of Chemistry, Johannes Gutenberg University, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Luca M Carrella
- Department of Chemistry, Johannes Gutenberg University, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Manfred Wagner
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Martin Panthöfer
- Department of Chemistry, Johannes Gutenberg University, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Angela Möller
- Department of Chemistry, Johannes Gutenberg University, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Eva Rentschler
- Department of Chemistry, Johannes Gutenberg University, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Katja Heinze
- Department of Chemistry, Johannes Gutenberg University, Duesbergweg 10-14, 55128 Mainz, Germany
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19
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Lehnert N, Kim E, Dong HT, Harland JB, Hunt AP, Manickas EC, Oakley KM, Pham J, Reed GC, Alfaro VS. The Biologically Relevant Coordination Chemistry of Iron and Nitric Oxide: Electronic Structure and Reactivity. Chem Rev 2021; 121:14682-14905. [PMID: 34902255 DOI: 10.1021/acs.chemrev.1c00253] [Citation(s) in RCA: 96] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Nitric oxide (NO) is an important signaling molecule that is involved in a wide range of physiological and pathological events in biology. Metal coordination chemistry, especially with iron, is at the heart of many biological transformations involving NO. A series of heme proteins, nitric oxide synthases (NOS), soluble guanylate cyclase (sGC), and nitrophorins, are responsible for the biosynthesis, sensing, and transport of NO. Alternatively, NO can be generated from nitrite by heme- and copper-containing nitrite reductases (NIRs). The NO-bearing small molecules such as nitrosothiols and dinitrosyl iron complexes (DNICs) can serve as an alternative vehicle for NO storage and transport. Once NO is formed, the rich reaction chemistry of NO leads to a wide variety of biological activities including reduction of NO by heme or non-heme iron-containing NO reductases and protein post-translational modifications by DNICs. Much of our understanding of the reactivity of metal sites in biology with NO and the mechanisms of these transformations has come from the elucidation of the geometric and electronic structures and chemical reactivity of synthetic model systems, in synergy with biochemical and biophysical studies on the relevant proteins themselves. This review focuses on recent advancements from studies on proteins and model complexes that not only have improved our understanding of the biological roles of NO but also have provided foundations for biomedical research and for bio-inspired catalyst design in energy science.
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Affiliation(s)
- Nicolai Lehnert
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Eunsuk Kim
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Hai T Dong
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Jill B Harland
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Andrew P Hunt
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Elizabeth C Manickas
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Kady M Oakley
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - John Pham
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Garrett C Reed
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Victor Sosa Alfaro
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
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20
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Üngör Ö, Choi ES, Shatruk M. Solvent‐Dependent Spin‐Crossover Behavior in Semiconducting Co–Crystals of [Fe(1‐bpp)
2
]
2+
Cations and TCNQ
δ−
Anions (0<δ<1). Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Ökten Üngör
- Department of Chemistry and Biochemistry Florida State University 95 Chieftan Way Tallahassee FL 32306 USA
- Department of Chemistry Colorado State University 301 W. Pitkin St Fort Collins CO 80523 USA
| | - Eun Sang Choi
- National High Magnetic Field Laboratory 1800 E Paul Dirac Dr Tallahassee FL 32310 USA
| | - Michael Shatruk
- Department of Chemistry and Biochemistry Florida State University 95 Chieftan Way Tallahassee FL 32306 USA
- National High Magnetic Field Laboratory 1800 E Paul Dirac Dr Tallahassee FL 32310 USA
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21
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Li R, Levchenko G, Valverde-Muñoz FJ, Gaspar AB, Ivashko VV, Li Q, Liu B, Yuan M, Fylymonov H, Real JA. Pressure Tunable Electronic Bistability in Fe(II) Hofmann-like Two-Dimensional Coordination Polymer [Fe(Fpz) 2Pt(CN) 4]: A Comprehensive Experimental and Theoretical Study. Inorg Chem 2021; 60:16016-16028. [PMID: 34633179 PMCID: PMC8564755 DOI: 10.1021/acs.inorgchem.1c02318] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
A comprehensive experimental
and theoretical study of both thermal-induced
spin transition (TIST) as a function of pressure and pressure-induced
spin transition (PIST) at room temperature for the two-dimensional
Hofmann-like SCO polymer [Fe(Fpz)2Pt(CN)4] is
reported. The TIST studies at different fixed pressures have been
carried out by magnetic susceptibility measurements, while PIST studies
have been performed by means of powder X-ray diffraction, Raman, and
visible spectroscopies. A combination of the theory of elastic interactions
and numerical Monte Carlo simulations has been used for the analysis
of the cooperative interactions in TIST and PIST studies. A complete
(T, P) phase diagram for the compound
[Fe(Fpz)2Pt(CN)4] has been constructed. The
critical temperature of the spin transition follows a lineal dependence
with pressure, meanwhile the hysteresis width shows a nonmonotonic
behavior contrary to theoretical predictions. The analysis shows the
exceptional role of the total entropy and phonon contribution in setting
the temperature of the spin transition and the width of the hysteresis.
The anomalous behavior of the thermal hysteresis width under pressure
in [Fe(Fpz)2Pt(CN)4] is a direct consequence
of a local distortion of the octahedral geometry of the Fe(II) centers
for pressures higher than 0.4 GPa. Interestingly, there is not a coexistence
of the high- and low-spin (HS and LS, respectively) phases in TIST
experiments, while in PIST experiments, the coexistence of the HS
and LS phases in the metastable region of the phase transition induced
by pressure is observed for a first time in a first-order gradual
spin transition with hysteresis. A comprehensive
experimental and theoretical study of both
thermal-induced spin transition as a function of pressure and pressure-induced
spin transition at room temperature for the two-dimensional Hofmann-like
SCO polymer [Fe(Fpz)2Pt(CN)4] is reported. A
complete (T, P) phase diagram for
compound [Fe(Fpz)2[Pt(CN)4] has been constructed.
The critical temperature of the spin transition follows a lineal dependence
with pressure, meanwhile the hysteresis width shows a nonmonotonic
behavior contrary to theoretical predictions.
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Affiliation(s)
- Ruixin Li
- State Key Laboratory of Superhard Materials, International Centre of Future Science, Jilin University, Changchun 130012, China
| | - Georgiy Levchenko
- State Key Laboratory of Superhard Materials, International Centre of Future Science, Jilin University, Changchun 130012, China.,Donetsk Institute of Physics and Engineering Named after A. A. Galkin, Kyiv 03028, Ukraine
| | | | - Ana Belén Gaspar
- Institut de Ciència Molecular, Departament de Química Inorgànica, Universitat de València, E-46980 València, Spain
| | - Victor V Ivashko
- Department of Correlation Optics, Chernivtsi National University, Chernivtsi 58012, Ukraine
| | - Quanjun Li
- State Key Laboratory of Superhard Materials, International Centre of Future Science, Jilin University, Changchun 130012, China
| | - Bingbing Liu
- State Key Laboratory of Superhard Materials, International Centre of Future Science, Jilin University, Changchun 130012, China
| | - Mengyun Yuan
- State Key Laboratory of Superhard Materials, International Centre of Future Science, Jilin University, Changchun 130012, China
| | - Hennagii Fylymonov
- Donetsk Institute of Physics and Engineering Named after A. A. Galkin, Kyiv 03028, Ukraine
| | - Jose Antonio Real
- Institut de Ciència Molecular, Departament de Química Inorgànica, Universitat de València, E-46980 València, Spain
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22
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Üngör Ö, Choi ES, Shatruk M. Optimization of crystal packing in semiconducting spin-crossover materials with fractionally charged TCNQ δ- anions (0 < δ < 1). Chem Sci 2021; 12:10765-10779. [PMID: 34476058 PMCID: PMC8372557 DOI: 10.1039/d1sc02843j] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 07/02/2021] [Indexed: 11/21/2022] Open
Abstract
Co-crystallization of the prominent Fe(ii) spin-crossover (SCO) cation, [Fe(3-bpp)2]2+ (3-bpp = 2,6-bis(pyrazol-3-yl)pyridine), with a fractionally charged TCNQ δ- radical anion has afforded a hybrid complex [Fe(3-bpp)2](TCNQ)3·5MeCN (1·5MeCN, where δ = -0.67). The partially desolvated material shows semiconducting behavior, with the room temperature conductivity σ RT = 3.1 × 10-3 S cm-1, and weak modulation of conducting properties in the region of the spin transition. The complete desolvation, however, results in the loss of hysteretic behavior and a very gradual SCO that spans the temperature range of 200 K. A related complex with integer-charged TCNQ- anions, [Fe(3-bpp)2](TCNQ)2·3MeCN (2·3MeCN), readily loses the interstitial solvent to afford desolvated complex 2 that undergoes an abrupt and hysteretic spin transition centered at 106 K, with an 11 K thermal hysteresis. Complex 2 also exhibits a temperature-induced excited spin-state trapping (TIESST) effect, upon which a metastable high-spin state is trapped by flash-cooling from room temperature to 10 K. Heating above 85 K restores the ground-state low-spin configuration. An approach to improve the structural stability of such complexes is demonstrated by using a related ligand 2,6-bis(benzimidazol-2'-yl)pyridine (bzimpy) to obtain [Fe(bzimpy)2](TCNQ)6·2Me2CO (4) and [Fe(bzimpy)2](TCNQ)5·5MeCN (5), both of which exist as LS complexes up to 400 K and exhibit semiconducting behavior, with σ RT = 9.1 × 10-2 S cm-1 and 1.8 × 10-3 S cm-1, respectively.
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Affiliation(s)
- Ökten Üngör
- Department of Chemistry and Biochemistry, Florida State University 95 Chieftan Way Tallahassee FL 32306 USA
| | - Eun Sang Choi
- National High Magnetic Field Laboratory 1800 E Paul Dirac Dr Tallahassee FL 32310 USA
| | - Michael Shatruk
- Department of Chemistry and Biochemistry, Florida State University 95 Chieftan Way Tallahassee FL 32306 USA
- National High Magnetic Field Laboratory 1800 E Paul Dirac Dr Tallahassee FL 32310 USA
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23
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Kucheriv OI, Fritsky IO, Gural'skiy IA. Spin crossover in FeII cyanometallic frameworks. Inorganica Chim Acta 2021. [DOI: 10.1016/j.ica.2021.120303] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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24
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Romanini M, Wang Y, Gürpinar K, Ornelas G, Lloveras P, Zhang Y, Zheng W, Barrio M, Aznar A, Gràcia-Condal A, Emre B, Atakol O, Popescu C, Zhang H, Long Y, Balicas L, Lluís Tamarit J, Planes A, Shatruk M, Mañosa L. Giant and Reversible Barocaloric Effect in Trinuclear Spin-Crossover Complex Fe 3 (bntrz) 6 (tcnset) 6. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2008076. [PMID: 33527567 DOI: 10.1002/adma.202008076] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/05/2021] [Indexed: 06/12/2023]
Abstract
A giant barocaloric effect (BCE) in a molecular material Fe3 (bntrz)6 (tcnset)6 (FBT) is reported, where bntrz = 4-(benzyl)-1,2,4-triazole and tcnset = 1,1,3,3-tetracyano-2-thioethylepropenide. The crystal structure of FBT contains a trinuclear transition metal complex that undergoes an abrupt spin-state switching between the state in which all three FeII centers are in the high-spin (S = 2) electronic configuration and the state in which all of them are in the low-spin (S = 0) configuration. Despite the strongly cooperative nature of the spin transition, it proceeds with a negligible hysteresis and a large volumetric change, suggesting that FBT should be a good candidate for producing a large BCE. Powder X-ray diffraction and calorimetry reveal that the material is highly susceptible to applied pressure, as the transition temperature spans the range from 318 at ambient pressure to 383 K at 2.6 kbar. Despite the large shift in the spin-transition temperature, its nonhysteretic character is maintained under applied pressure. Such behavior leads to a remarkably large and reversible BCE, characterized by an isothermal entropy change of 120 J kg-1 K-1 and an adiabatic temperature change of 35 K, which are among the highest reversible values reported for any caloric material thus far.
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Affiliation(s)
- Michela Romanini
- Departament de Física de la Matèria Condensada, Facultat de Física, Martí i Franquès 1, Universitat de Barcelona, Barcelona, Catalonia, 08028, Spain
| | - YiXu Wang
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, 32306, USA
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China
| | - Kübra Gürpinar
- Department of Chemistry, Faculty of Science, Ankara University, Ankara, 06100, Turkey
| | - Gladys Ornelas
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, 32306, USA
- G. W. Brackenridge High School, San Antonio, TX, 78210, USA
| | - Pol Lloveras
- Grup de Caracterització de Materials, Departament de Física, EEBE and Barcelona Research Center in Multiscale Science and Engineering, Universitat Politècnica de Catalunya, Eduard Maristany, 10-14, Barcelona, Catalonia, 08019, Spain
| | - Yan Zhang
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, 32306, USA
| | - Wenkai Zheng
- National High Magnetic Field Laboratory, Tallahassee, FL, 32310, USA
| | - Maria Barrio
- Grup de Caracterització de Materials, Departament de Física, EEBE and Barcelona Research Center in Multiscale Science and Engineering, Universitat Politècnica de Catalunya, Eduard Maristany, 10-14, Barcelona, Catalonia, 08019, Spain
| | - Araceli Aznar
- Grup de Caracterització de Materials, Departament de Física, EEBE and Barcelona Research Center in Multiscale Science and Engineering, Universitat Politècnica de Catalunya, Eduard Maristany, 10-14, Barcelona, Catalonia, 08019, Spain
| | - Adrià Gràcia-Condal
- Departament de Física de la Matèria Condensada, Facultat de Física, Martí i Franquès 1, Universitat de Barcelona, Barcelona, Catalonia, 08028, Spain
| | - Baris Emre
- Department of Engineering Physics, Faculty of Engineering, Ankara University, Ankara, 06100, Turkey
| | - Orhan Atakol
- Department of Chemistry, Faculty of Science, Ankara University, Ankara, 06100, Turkey
| | - Catalin Popescu
- CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Catalonia, E-08290, Spain
| | - Hu Zhang
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China
| | - Yi Long
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P. R. China
| | - Luis Balicas
- National High Magnetic Field Laboratory, Tallahassee, FL, 32310, USA
| | - Josep Lluís Tamarit
- Grup de Caracterització de Materials, Departament de Física, EEBE and Barcelona Research Center in Multiscale Science and Engineering, Universitat Politècnica de Catalunya, Eduard Maristany, 10-14, Barcelona, Catalonia, 08019, Spain
| | - Antoni Planes
- Departament de Física de la Matèria Condensada, Facultat de Física, Martí i Franquès 1, Universitat de Barcelona, Barcelona, Catalonia, 08028, Spain
| | - Michael Shatruk
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, 32306, USA
- National High Magnetic Field Laboratory, Tallahassee, FL, 32310, USA
| | - Lluís Mañosa
- Departament de Física de la Matèria Condensada, Facultat de Física, Martí i Franquès 1, Universitat de Barcelona, Barcelona, Catalonia, 08028, Spain
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25
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Heras Ojea MJ, Van Raden JM, Louie S, Collins R, Pividori D, Cirera J, Meyer K, Jasti R, Layfield RA. Spin‐Crossover Properties of an Iron(II) Coordination Nanohoop. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202013374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | - Jeff M. Van Raden
- Department of Chemistry and Biochemistry and Materials Science Institute University of Oregon Eugene OR 97403 USA
| | - Shayan Louie
- Department of Chemistry and Biochemistry and Materials Science Institute University of Oregon Eugene OR 97403 USA
| | - Richard Collins
- Department of Chemistry University of Sussex Brighton BN1 9QJ UK
| | - Daniel Pividori
- Department of Chemistry and Pharmacy Inorganic Chemistry Friedrich-Alexander University Erlangen-Nürnberg (FAU) Egerlandstrasse 1 91058 Erlangen Germany
| | - Jordi Cirera
- Departament de Química Inorgànica i Orgànica and Institut de Recerca de Química Teòrica i Computacional Universitat de Barcelona Diagonal 645 08028 Barcelona Spain
| | - Karsten Meyer
- Department of Chemistry and Pharmacy Inorganic Chemistry Friedrich-Alexander University Erlangen-Nürnberg (FAU) Egerlandstrasse 1 91058 Erlangen Germany
| | - Ramesh Jasti
- Department of Chemistry and Biochemistry and Materials Science Institute University of Oregon Eugene OR 97403 USA
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26
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Deorukhkar N, Besnard C, Guénée L, Piguet C. Tuning spin-crossover transition temperatures in non-symmetrical homoleptic meridional/facial [Fe(didentate) 3] 2+ complexes: what for and who cares about it? Dalton Trans 2021; 50:1206-1223. [PMID: 33404561 DOI: 10.1039/d0dt03828h] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The [FeN6] chromophores found in [Fe(didentate)3]2+ complexes, where didentate is a non-symmetrical 2-(6-membered-heterocyclic ring)-benzimidazole ligand (Lk), exist as mixtures of two geometrical mer (C1-symmetry) and fac (C3-symmetry) isomers. Specific alkyl-substituted six-membered heterocyclic rings connected to the benzimidazole unit (pyridines in ligands L1-L3, pyrazines in L4-L5 and pyrimidines in L6-L7) control the ligand field strength and the electron delocalization so that [FeII(Lk)3]2+ display tunable thermally-induced spin transitions in solution. Thermodynamic, spectroscopic (UV-Vis, NMR) and magnetic studies in solution demonstrate that [Fe(L6)3]2+ (L6 = 1-methyl-2-(pyrimidin-2-yl)-1H-benzo[d]imidazole) exhibits a close to room temperature spin transition (T1/2 = 273(3) K) combined with a high stability formation constant ( in acetonitrile), which makes this complex suitable for the potential modulation of lanthanide-based luminescence in polymetallic helicates. A novel method is proposed for assigning specific thermodynamic spin crossover parameters to fac-[Fe(L6)3]2+ and mer-[Fe(L6)3]2+ isomers in solution. The observed difference relies mainly on the entropic content ΔS-ΔS = 11(1) J mol-1 K-1, which favors the spin transition for the meridional isomer. Intermolecular interactions occurring in the crystalline state largely overcome minor thermodynamic trends operating in diluted solutions and a single configurational isomer is usually observed in the solid state. Among the thirteen solved crystal structures 1-13 containing the [M(Lk)3]2+ cations (M = Fe, Ni, Zn, Lk = L6-L7), pure meridional isomers are observed six times, pure facial isomers also six times and a mixture (44% mer and 56% fac) is detected only once. Solid-state magnetic data recorded for the FeII complexes show the operation of slightly cooperative spin transitions in 7 (fac-[Fe(L6)3]2+) and 12 (mer-[Fe(L7)3]2+). For the meridional isomer in 6, a two-step spin state transition curve, associated with two phase transitions, is detected.
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Affiliation(s)
- Neel Deorukhkar
- Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai E. Ansermet, CH-1211 Geneva 4, Switzerland.
| | - Céline Besnard
- Laboratory of Crystallography, University of Geneva, 24 quai E. Ansermet, CH-1211 Geneva 4, Switzerland
| | - Laure Guénée
- Laboratory of Crystallography, University of Geneva, 24 quai E. Ansermet, CH-1211 Geneva 4, Switzerland
| | - Claude Piguet
- Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai E. Ansermet, CH-1211 Geneva 4, Switzerland.
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27
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Janet JP, Duan C, Nandy A, Liu F, Kulik HJ. Navigating Transition-Metal Chemical Space: Artificial Intelligence for First-Principles Design. Acc Chem Res 2021; 54:532-545. [PMID: 33480674 DOI: 10.1021/acs.accounts.0c00686] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The variability of chemical bonding in open-shell transition-metal complexes not only motivates their study as functional materials and catalysts but also challenges conventional computational modeling tools. Here, tailoring ligand chemistry can alter preferred spin or oxidation states as well as electronic structure properties and reactivity, creating vast regions of chemical space to explore when designing new materials atom by atom. Although first-principles density functional theory (DFT) remains the workhorse of computational chemistry in mechanism deduction and property prediction, it is of limited use here. DFT is both far too computationally costly for widespread exploration of transition-metal chemical space and also prone to inaccuracies that limit its predictive performance for localized d electrons in transition-metal complexes. These challenges starkly contrast with the well-trodden regions of small-organic-molecule chemical space, where the analytical forms of molecular mechanics force fields and semiempirical theories have for decades accelerated the discovery of new molecules, accurate DFT functional performance has been demonstrated, and gold-standard methods from correlated wavefunction theory can predict experimental results to chemical accuracy.The combined promise of transition-metal chemical space exploration and lack of established tools has mandated a distinct approach. In this Account, we outline the path we charted in exploration of transition-metal chemical space starting from the first machine learning (ML) models (i.e., artificial neural network and kernel ridge regression) and representations for the prediction of open-shell transition-metal complex properties. The distinct importance of the immediate coordination environment of the metal center as well as the lack of low-level methods to accurately predict structural properties in this coordination environment first motivated and then benefited from these ML models and representations. Once developed, the recipe for prediction of geometric, spin state, and redox potential properties was straightforwardly extended to a diverse range of other properties, including in catalysis, computational "feasibility", and the gas separation properties of periodic metal-organic frameworks. Interpretation of selected features most important for model prediction revealed new ways to encapsulate design rules and confirmed that models were robustly mapping essential structure-property relationships. Encountering the special challenge of ensuring that good model performance could generalize to new discovery targets motivated investigation of how to best carry out model uncertainty quantification. Distance-based approaches, whether in model latent space or in carefully engineered feature space, provided intuitive measures of the domain of applicability. With all of these pieces together, ML can be harnessed as an engine to tackle the large-scale exploration of transition-metal chemical space needed to satisfy multiple objectives using efficient global optimization methods. In practical terms, bringing these artificial intelligence tools to bear on the problems of transition-metal chemical space exploration has resulted in ML-model assessments of large, multimillion compound spaces in minutes and validated new design leads in weeks instead of decades.
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Affiliation(s)
- Jon Paul Janet
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Chenru Duan
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Aditya Nandy
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Fang Liu
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Heather J. Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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28
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Milocco F, de Vries F, Siebe HS, Engbers S, Demeshko S, Meyer F, Otten E. Widening the Window of Spin-Crossover Temperatures in Bis(formazanate)iron(II) Complexes via Steric and Noncovalent Interactions. Inorg Chem 2021; 60:2045-2055. [PMID: 33464882 PMCID: PMC7856632 DOI: 10.1021/acs.inorgchem.0c03593] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Bis(formazanate)iron(II) complexes
undergo a thermally induced S = 0 to S = 2 spin transition in solution.
Here we present a study of how steric effects and π-stacking
interactions between the triarylformazanate ligands affect the
spin-crossover behavior, in addition to electronic substituent effects.
Moreover, the effect of increasing the denticity of the formazanate
ligands is explored by including additional OMe donors in the ligand
(7). In total, six new compounds (2–7) have been synthesized and characterized, both in solution
and in the solid state, via spectroscopic, magnetic, and structural
analyses. The series spans a broad range of spin-crossover temperatures
(T1/2) for the LS ⇌ HS equilibrium
in solution, with the exception of compound 6 which remains
high-spin (S = 2) down to 210 K. In the solid state, 6 was shown to exist in two distinct forms: a tetrahedral
high-spin complex (6a, S = 2) and a
rare square-planar structure with an intermediate-spin state (6b, S = 1). SQUID measurements, 57Fe Mössbauer spectroscopy, and differential scanning calorimetry
indicate that in the solid state the square-planar form 6b undergoes an incomplete spin-change-coupled isomerization to tetrahedral 6a. The complex that contains additional OMe donors (7) results in a six-coordinate (NNO)2Fe coordination
geometry, which shifts the spin-crossover to significantly higher
temperatures (T1/2 = 444 K). The available
experimental and computational data for 7 suggest that
the Fe···OMe interaction is retained upon spin-crossover.
Despite the difference in coordination environment, the weak OMe donors
do not significantly alter the electronic structure or ligand-field
splitting, and the occurrence of spin-crossover (similar to the compounds
lacking the OMe groups) originates from a large degree of metal–ligand
π-covalency. A series of
Fe(II) complexes with formazanate ligands are
reported, and ligand substituent effects on structure and spin-crossover
properties are examined. These ligand modifications allow isolation
of compounds with tetrahedral geometries in both low- and high-spin
ground states as well as an intermediate-spin square-planar complex.
Steric properties, π-stacking interactions, and additional donor
substituents lead to a wide range of spin-crossover temperatures (T1/2) in this class of compounds.
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Affiliation(s)
- Francesca Milocco
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Folkert de Vries
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Harmke S Siebe
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Silène Engbers
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Serhiy Demeshko
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstraße 4, 37077 Göttingen, Germany
| | - Franc Meyer
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstraße 4, 37077 Göttingen, Germany
| | - Edwin Otten
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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29
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Heras Ojea MJ, Van Raden JM, Louie S, Collins R, Pividori D, Cirera J, Meyer K, Jasti R, Layfield RA. Spin-Crossover Properties of an Iron(II) Coordination Nanohoop. Angew Chem Int Ed Engl 2020; 60:3515-3518. [PMID: 33112017 DOI: 10.1002/anie.202013374] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Indexed: 12/20/2022]
Abstract
Addition of the bipyridyl-embedded cycloparaphenylene nanohoop bipy[9]CPP to [Fe{H2 B(pyz)2 }] (pyz=pyrazolyl) produces the distorted octahedral complex [Fe(bipy[9]CPP){H2 B(pyz)2 }2 ] (1). The molecular structure of 1 shows that the nanohoop ligand contains a non-planar bipy unit. Magnetic susceptibility measurements indicate spin-crossover (SCO) behaviour with a T1/2 of 130 K, lower than that of 160 K observed with the related compound [Fe(bipy){H2 B(pyz)2 }2 ] (2), which contains a conventional bipy ligand. A computational study of 1 and 2 reveals that the curvature of the nanohoop leads to the different SCO properties, suggesting that the SCO behaviour of iron(II) can be tuned by varying the size and diameter of the nanohoop.
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Affiliation(s)
| | - Jeff M Van Raden
- Department of Chemistry and Biochemistry and Materials Science Institute, University of Oregon, Eugene, OR, 97403, USA
| | - Shayan Louie
- Department of Chemistry and Biochemistry and Materials Science Institute, University of Oregon, Eugene, OR, 97403, USA
| | - Richard Collins
- Department of Chemistry, University of Sussex, Brighton, BN1 9QJ, UK
| | - Daniel Pividori
- Department of Chemistry and Pharmacy, Inorganic Chemistry, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Jordi Cirera
- Departament de Química Inorgànica i Orgànica and Institut de Recerca de Química Teòrica i Computacional, Universitat de Barcelona, Diagonal 645, 08028, Barcelona, Spain
| | - Karsten Meyer
- Department of Chemistry and Pharmacy, Inorganic Chemistry, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Ramesh Jasti
- Department of Chemistry and Biochemistry and Materials Science Institute, University of Oregon, Eugene, OR, 97403, USA
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30
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Ivanova AD, Lavrenova LG, Korotaev EV, Trubina SV, Sheludyakova LA, Petrov SA, Zhizhin KY, Kuznetsov NT. High-Temperature Spin Crossover in Complexes of Iron(II) closo-Borates with 2,6-Bis(benzimidazol-2-yl)pyridine. RUSS J INORG CHEM+ 2020. [DOI: 10.1134/s0036023620110078] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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31
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Sirenko VY, Kucheriv OI, Rotaru A, Fritsky IO, Gural'skiy IA. Direct Synthesis of Spin‐Crossover Complexes: An Unexpectedly Revealed New Iron‐Triazolic Structure. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000848] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Valerii Y. Sirenko
- Department of Chemistry Taras Shevchenko National University of Kyiv Volodymyrska St. 64 01601 Kyiv Ukraine
| | - Olesia I. Kucheriv
- Department of Chemistry Taras Shevchenko National University of Kyiv Volodymyrska St. 64 01601 Kyiv Ukraine
- UkrOrgSyntez Ltd Chervonotkatska St. 67 02094 Kyiv Ukraine
| | - Aurelian Rotaru
- Faculty of Electrical Engineering and Computer Science and MANSiD Research Center Stefan cel Mare University Universității St. 13 720229 Suceava Romania
| | - Igor O. Fritsky
- Department of Chemistry Taras Shevchenko National University of Kyiv Volodymyrska St. 64 01601 Kyiv Ukraine
- UkrOrgSyntez Ltd Chervonotkatska St. 67 02094 Kyiv Ukraine
| | - Il'ya A. Gural'skiy
- Department of Chemistry Taras Shevchenko National University of Kyiv Volodymyrska St. 64 01601 Kyiv Ukraine
- UkrOrgSyntez Ltd Chervonotkatska St. 67 02094 Kyiv Ukraine
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32
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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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33
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Yuan M, Levchenko G, Li Q, Berezhnaya L, Fylymonov H, Gaspar AB, Seredyuk M, Real JA. Variable Cooperative Interactions in the Pressure and Thermally Induced Multistep Spin Transition in a Two-Dimensional Iron(II) Coordination Polymer. Inorg Chem 2020; 59:10548-10556. [PMID: 32657582 DOI: 10.1021/acs.inorgchem.0c00978] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two types of experiments conducted to investigate the effect of pressure on the spin crossover (SCO) properties of the 2D Fe(II) coordination polymer formulated {Fe[bipy(ttr)2]}n are reported, namely, (1) magnetic measurements performed at variable temperature and at fixed pressure and (2) visible spectroscopy at variable pressure and fixed temperature. The magnetic experiments carried out under a hydrostatic pressure constraint of 0.04, 0.08, and 0.8 GPa reveal a two-step spin transition behavior. The characteristic critical temperatures of the spin transition are shifted upward in temperature as pressure increases. The slope of the straight-line of the Tc vs P plot, dTc/dP, is 775 K/GPa and 300 K/GPa, for the high temperature and the low temperature steps, respectively. These values are remarkably large and denote the extreme sensitivity of the material to the application of pressure. Indeed, the visible spectroscopic measurements performed at 293 K show that a complete spin transition is induced at pressures as low as 0.4 GPa. Moreover, the pressure-induced spin transition is reversible and shows an asymmetric hysteresis. An analysis of the cooperative interactions of the thermal- and pressure-induced spin transition in the framework of the model of elastic interactions reveals that the elastic energy of the lattice as well as the interaction parameter between the SCO centers change during the course of the spin transition. Consequently, the character of the spin transition varies from abrupt for the high temperature step to continuous for the low temperature step.
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Affiliation(s)
- Mengyun Yuan
- State Key Laboratory of Superhard Materials, International Centre of Future Science, Jilin University, Changchun 130012, China
| | - Georgiy Levchenko
- State Key Laboratory of Superhard Materials, International Centre of Future Science, Jilin University, Changchun 130012, China.,Donetsk Physical - Technical Institute named after A. A. Galkin NANU, Kiiv 03028, Ukraine
| | - Quanjun Li
- State Key Laboratory of Superhard Materials, International Centre of Future Science, Jilin University, Changchun 130012, China
| | - Ludmila Berezhnaya
- Donetsk Institute of Physics and Engineering named after A. A. Galkin, Donestk 83114, Ukraine
| | - Hennagii Fylymonov
- Southern Federal University, Rostov-na-Donu, Russia, Donetsk 83050, Ukraine
| | - Ana Belén Gaspar
- Institut de Ciència Molecular/Departament de Química Inorgànica, Universitat de València, Catedràtric Beltrán 2, E-46980 Paterna, València, Spain
| | - Maksym Seredyuk
- Institut de Ciència Molecular/Departament de Química Inorgànica, Universitat de València, Catedràtric Beltrán 2, E-46980 Paterna, València, Spain
| | - José Antonio Real
- Institut de Ciència Molecular/Departament de Química Inorgànica, Universitat de València, Catedràtric Beltrán 2, E-46980 Paterna, València, Spain
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34
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The Tyranny of Arm-Wrestling Methyls on Iron(II) Spin State in Pseudo-Octahedral [Fe(didentate)3] Complexes. CHEMISTRY 2020. [DOI: 10.3390/chemistry2020015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The connection of a sterically constrained 3-methyl-pyrazine ring to a N-methyl-benzimidazole unit to give the unsymmetrical α,α’-diimine ligand L5 has been programmed for the design of pseudo-octahedral spin-crossover [Fe(L5)3]2+ units, the transition temperature (T1/2) of which occurs in between those reported for related facial tris-didentate iron chromophores fitted with 3-methyl-pyridine-benzimidazole in a LaFe helicate (T1/2 ~ 50 K) and with 5-methyl-pyrazine-benzimidazole L2 ligands (T1/2 ~350 K). A thorough crystallographic analysis of [Fe(L5)3](ClO4)2 (I), [Ni(L5)3](ClO4)2 (II), [Ni(L5)3](BF4)2∙H2O (III), [Zn(L5)3](ClO4)2 (IV), [Ni(L5)3](BF4)2∙1.75CH3CN (V), and [Zn(L5)3](BF4)2∙1.5CH3CN (VI) shows the selective formation of pure facial [M(L5)3]2+ cations in the solvated crystals of the tetrafluoroborate salts and alternative meridional isomers in the perchlorate salts. Except for a slightly larger intra-strand interannular twist between the aromatic heterocycles in L5, the metric parameters measured in [Zn(L5)3]2+ are comparable to those reported for [Zn(L2)3]2+, where L2 is the related unconstrained ligand. This similitude is reinforced by comparable ligand-field strengths (∆oct) and nephelauxetic effects (as measured by the Racah parameters B and C) extracted from the electronic absorption spectra recorded for [Ni(L5)3]2+ and [Ni(L2)3]2+. In this context, the strictly high-spin behavior observed for [Fe(L5)3]2+ within the 5–300 K range contrasts with the close to room-temperature spin-crossover behavior of [Fe(L2)3]2+ (T1/2 = 349(5) K in acetonitrile). This can be unambiguously assigned to an intraligand arm wrestling match operating in bound L5, which prevents the contraction of the coordination sphere required for accommodating low-spin FeII. Since the analogous 3-methyl-pyridine ring in [Fe(L3)3]2+ derivatives are sometimes compatible with spin-crossover properties, the consequences of repulsive intra-strand methyl–methyl interactions are found to be amplified in [Fe(L5)3]2+ because of the much lower basicity of the 3-methyl-pyrazine ring and the resulting weaker thermodynamic compensation. The decrease of the stability constants by five orders of magnitude observed in going from [M(L2)3]2+ to [M(L5)3]2+ (M = NiII and ZnII) is diagnostic for the operation of this effect, which had been not foreseen by the authors.
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35
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Naumova MA, Kalinko A, Wong JWL, Abdellah M, Geng H, Domenichini E, Meng J, Gutierrez SA, Mante PA, Lin W, Zalden P, Galler A, Lima F, Kubicek K, Biednov M, Britz A, Checchia S, Kabanova V, Wulff M, Zimara J, Schwarzer D, Demeshko S, Murzin V, Gosztola D, Jarenmark M, Zhang J, Bauer M, Lawson Daku ML, Gawelda W, Khakhulin D, Bressler C, Meyer F, Zheng K, Canton SE. Revealing Hot and Long-Lived Metastable Spin States in the Photoinduced Switching of Solvated Metallogrid Complexes with Femtosecond Optical and X-ray Spectroscopies. J Phys Chem Lett 2020; 11:2133-2141. [PMID: 32069410 DOI: 10.1021/acs.jpclett.9b03883] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
An atomistic understanding of the photoinduced spin-state switching (PSS) within polynuclear systems of d4-d7 transition metal ion complexes is required for their rational integration into light-driven reactions of chemical and biological interest. However, in contrast to mononuclear systems, the multidimensional dynamics of the PSS in solvated molecular arrays have not yet been elucidated due to the expected complications associated with the connectivity between the metal centers and the strong interactions with the surroundings. In this work, the PSS in a solvated triiron(II) metallogrid complex is characterized using transient optical absorption and X-ray emission spectroscopies on the femtosecond time scale. The complementary measurements reveal the photoinduced creation of energy-rich (hot) and long-lived quintet states, whose dynamics differ critically from their mononuclear congeners. This finding opens major prospects for developing novel schemes in solution-phase spin chemistry that are driven by the dynamic PSS process in compact oligometallic arrays.
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Affiliation(s)
- Maria A Naumova
- Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607 Hamburg, Germany
| | - Aleksandr Kalinko
- Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607 Hamburg, Germany
- Department Chemie and Center for Sustainable Systems Design (CSSD), University of Paderborn, Warburger Straße 100, D-33098 Paderborn, Germany
| | - Joanne W L Wong
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstraße 4, 37077 Göttingen, Germany
| | - Mohamed Abdellah
- Chemical Physics and NanoLund, Lund University, Box 124, 22100 Lund, Sweden
- Department of Chemistry, Qena Faculty of Science, South Valley University, 83523 Qena, Egypt
| | - Huifang Geng
- ELI-ALPS, ELI-HU Non-Profit Ltd., Dugonics ter 13, Szeged 6720, Hungary
| | | | - Jie Meng
- Department of Chemistry, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Sol Alvarez Gutierrez
- Department of Chemistry, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Pierre-Adrien Mante
- Chemical Physics and NanoLund, Lund University, Box 124, 22100 Lund, Sweden
- Department of Applied Physics, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Weihua Lin
- Chemical Physics and NanoLund, Lund University, Box 124, 22100 Lund, Sweden
| | - Peter Zalden
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | | | | | | | | | | | - Victoria Kabanova
- European Synchrotron Radiation Facility (ESRF), 38000 Grenoble Cedex 9, France
| | - Michael Wulff
- European Synchrotron Radiation Facility (ESRF), 38000 Grenoble Cedex 9, France
| | - Jennifer Zimara
- Department of Dynamics at Surfaces, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Dirk Schwarzer
- Department of Dynamics at Surfaces, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Serhiy Demeshko
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstraße 4, 37077 Göttingen, Germany
| | - Vadim Murzin
- Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607 Hamburg, Germany
- Bergische Universität Wuppertal, Gaußstraße 20, 42119 Wuppertal, Germany
| | - David Gosztola
- Center for Nanoscale Materials, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, United States
| | | | - Jianxin Zhang
- State Key Laboratory of Hollow Fiber Membrane Materials and Processes, School of Environmental and Chemical Engineering, Tianjin Polytechnic University, Tianjin 300387, China
| | - Matthias Bauer
- Department Chemie and Center for Sustainable Systems Design (CSSD), University of Paderborn, Warburger Straße 100, D-33098 Paderborn, Germany
| | - Max Latevi Lawson Daku
- Département de Chimie Physique, Université de Genève, Quai E. Ansermet 30, CH-1211 Genève 4, Switzerland
| | - Wojciech Gawelda
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
- Faculty of Physics, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 2, 61-614 Poznań, Poland
| | | | - Christian Bressler
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
- The Hamburg Centre for Ultrafast Imaging, University of Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Franc Meyer
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstraße 4, 37077 Göttingen, Germany
| | - Kaibo Zheng
- Chemical Physics and NanoLund, Lund University, Box 124, 22100 Lund, Sweden
- Department of Chemistry, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Sophie E Canton
- Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607 Hamburg, Germany
- ELI-ALPS, ELI-HU Non-Profit Ltd., Dugonics ter 13, Szeged 6720, Hungary
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36
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Ivanova AD, Korotaev EV, Komarov VY, Sheludyakova LA, Varnek VA, Lavrenova LG. Spin-crossover in iron( ii) coordination compounds with 2,6-bis(benzimidazol-2-yl)pyridine. NEW J CHEM 2020. [DOI: 10.1039/d0nj00474j] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Novel iron(ii) bromide, nitrate and dicyanamide complexes with 2,6-bis(benzimidazol-2-yl)pyridine possessing high-temperature 1A1 ↔ 5T2 spin crossover were obtained.
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Affiliation(s)
- A. D. Ivanova
- Institute of Inorganic Chemistry Siberian Division of RAS
- Novosibirsk
- Russia
| | - E. V. Korotaev
- Institute of Inorganic Chemistry Siberian Division of RAS
- Novosibirsk
- Russia
| | - V. Yu. Komarov
- Institute of Inorganic Chemistry Siberian Division of RAS
- Novosibirsk
- Russia
- Novosibirsk National Research State University
- Novosibirsk
| | - L. A. Sheludyakova
- Institute of Inorganic Chemistry Siberian Division of RAS
- Novosibirsk
- Russia
| | - V. A. Varnek
- Institute of Inorganic Chemistry Siberian Division of RAS
- Novosibirsk
- Russia
| | - L. G. Lavrenova
- Institute of Inorganic Chemistry Siberian Division of RAS
- Novosibirsk
- Russia
- Novosibirsk National Research State University
- Novosibirsk
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37
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Shakirova O, Korotaev E, Evtushok D, Kuratieva N, Sheludyakova L, Shestopalov M, Lavrenova L. Spin-crossover in iron(II) complexes with tris(pyrazol-1-yl)methane and сluster anions [{W6X8}X6]2– (X = Cl, Br, I). J Mol Struct 2019. [DOI: 10.1016/j.molstruc.2019.03.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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38
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Structural Insights into the Two-Step Spin-Crossover Compound Fe(3,4-dimethyl-pyridine)2[Ag(CN)2]2. CRYSTALS 2019. [DOI: 10.3390/cryst9060316] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The crystal structure of the polymeric spin crossover compound Fe(3,4-dimethyl-pyridine)2[Ag(CN)2]2 has been solved and its temperature dependence followed by means of single-crystal and powder X-ray diffraction. This compound presents a two-step spin transition with relatively abrupt steps centred at ca. 170 K and 145 K and a plateau at around 155 K. The origin of the two-step transition is discussed in light of these structural studies. The observations are compatible with a mostly disordered state between the two steps, consisting of mixing of high-spin and low-spin species, while weak substructure reflections in the mixed phase could indicate some degree of long-range order of the high-spin and low-spin sites.
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39
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Dragulescu-Andrasi A, Hietsoi O, Üngör Ö, Dunk PW, Stubbs V, Arroyave A, Kovnir K, Shatruk M. Dicyanometalates as Building Blocks for Multinuclear Iron(II) Spin-Crossover Complexes. Inorg Chem 2019; 58:11920-11926. [PMID: 31136155 DOI: 10.1021/acs.inorgchem.9b01121] [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
A synthetic strategy featuring dicyanometalates [M(CN)2]- (M = Ag, Au) as N-coordinating ditopic linkers connecting partially blocked FeII centers has been employed to produce heterometallic hexanuclear complexes, which exhibit spin-crossover (SCO) behavior at the FeII sites. The reaction between tris(2-pyridylmethyl)amine (tpma)-capped FeII ions and [Ag(CN)2]- proceeded with partial decomposition of the dicyanoargentate and led to the formation of {[Fe(tpma)]4(μ-CN)2[μ-Ag(CN)2]2}(ClO4)4·3H2O (1), in which both [Ag(CN)2]- and CN- act as bridging ligands, and the opposite [Ag(CN)2]- bridges are engaged in a pronounced argentophilic d10-d10 interaction. In an analogous synthesis, the more stable [Au(CN)2]- species remained intact and furnished the complex {[Fe(tpma)]2[μ-Au2(CN)4]2} (2), which features two FeII centers bridged by two [Au2(CN)4]2- dimers. The use of S,S'-bis(2-pyridylmethyl)-1,2-thioethane (bpte) as a mixed-donor, N2S2-coordinating capping ligand yielded {[Fe(bpte)]2[μ-Au2(CN)4]2} (3), with a structure analogous to that of 2. Variable-temperature magnetic susceptibility measurements revealed that complexes 1-3 exhibit an onset of SCO above 350 K. Measurements above 400 K further confirmed the occurrence of a gradual spin-state conversion for complex 2.
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Affiliation(s)
- Alina Dragulescu-Andrasi
- Department of Chemistry and Biochemistry , Florida State University , 95 Chieftan Way , Tallahassee , Florida 32306 , United States
| | - Oleksandr Hietsoi
- Department of Chemistry and Biochemistry , Florida State University , 95 Chieftan Way , Tallahassee , Florida 32306 , United States
| | - Ökten Üngör
- Department of Chemistry and Biochemistry , Florida State University , 95 Chieftan Way , Tallahassee , Florida 32306 , United States
| | - Paul W Dunk
- Department of Chemistry and Biochemistry , Florida State University , 95 Chieftan Way , Tallahassee , Florida 32306 , United States
| | - Victoria Stubbs
- Department of Chemistry and Biochemistry , Florida State University , 95 Chieftan Way , Tallahassee , Florida 32306 , United States
| | - Alejandra Arroyave
- Department of Chemistry and Biochemistry , Florida State University , 95 Chieftan Way , Tallahassee , Florida 32306 , United States
| | - Kirill Kovnir
- Department of Chemistry and Biochemistry , Florida State University , 95 Chieftan Way , Tallahassee , Florida 32306 , United States
| | - Michael Shatruk
- Department of Chemistry and Biochemistry , Florida State University , 95 Chieftan Way , Tallahassee , Florida 32306 , United States
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40
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Abstract
We report herein on five new Fe(II) complexes of general formula [Fe(L)2(NCCH3)2](BF4)2•xCH3CN (L = substituted 2-pyridylimine-based ligands). The influence of proximally located electron withdrawing groups (e.g., NO2, CN, CF3, Cl, Br) bound to coordinated pyridylimine ligands has been studied for the effect on spin crossover in their Fe(II) complexes. Variable-temperature UV-visible spectroscopic studies performed on complexes with more strongly electronegative ligand substituents revealed spin crossover (SCO) in the solution, and thermodynamic parameters associated with the spin crossover were estimated.
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41
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Geoghegan BL, Phonsri W, Horton PN, Orton JB, Coles SJ, Murray KS, Cragg PJ, Dymond MK, Gass IA. Hysteretic thermal spin-crossover in heteroleptic Fe(ii) complexes using alkyl chain substituted 2,2′-dipyridylamine ligands. Dalton Trans 2019; 48:17340-17348. [DOI: 10.1039/c9dt03412a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The complexes trans-[FeII(LC4)2(NCS)2] (1C4) and trans-[FeII(LC10)2(NCS)2] (1C10) undergo thermally hysteretic spin-crossover with T1/2 = 127.5 K and 119.0 K respectively.
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Affiliation(s)
- Blaise L. Geoghegan
- School of Pharmacy and Biomolecular Sciences
- Huxley Building
- University of Brighton
- Brighton
- UK
| | - Wasinee Phonsri
- School of Chemistry
- Building 23
- Monash University
- Clayton
- Australia
| | - Peter N. Horton
- The UK National Crystallography Service
- School of Chemistry
- University of Southampton
- Southampton
- UK
| | - James B. Orton
- The UK National Crystallography Service
- School of Chemistry
- University of Southampton
- Southampton
- UK
| | - Simon J. Coles
- The UK National Crystallography Service
- School of Chemistry
- University of Southampton
- Southampton
- UK
| | - Keith S. Murray
- School of Chemistry
- Building 23
- Monash University
- Clayton
- Australia
| | - Peter J. Cragg
- School of Pharmacy and Biomolecular Sciences
- Huxley Building
- University of Brighton
- Brighton
- UK
| | - Marcus K. Dymond
- School of Pharmacy and Biomolecular Sciences
- Huxley Building
- University of Brighton
- Brighton
- UK
| | - Ian A. Gass
- School of Pharmacy and Biomolecular Sciences
- Huxley Building
- University of Brighton
- Brighton
- UK
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42
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Lazaro SE, Alkaş A, Lee SJ, Telfer SG, Murray KS, Phonsri W, Harding P, Harding DJ. Abrupt spin crossover in iron(iii) complexes with aromatic anions. Dalton Trans 2019; 48:15515-15520. [DOI: 10.1039/c9dt02373a] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two iron(iii) complexes, [Fe(qsal-X)2]OTs·nH2O, are found to exhibit abrupt spin crossover with the spin transition temperature substituent dependent, and X⋯O halogen bonds linking the spin centres.
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Affiliation(s)
- Sharon E. Lazaro
- Functional Materials and Nanotechnology Center of Excellence
- Walailak University
- Thasala
- Thailand
| | - Adil Alkaş
- MacDiarmid Institute for Advanced Materials and Nanotechnology
- Institute of Fundamental Sciences
- Massey University
- New Zealand
| | - Seok J. Lee
- MacDiarmid Institute for Advanced Materials and Nanotechnology
- Institute of Fundamental Sciences
- Massey University
- New Zealand
| | - Shane G. Telfer
- MacDiarmid Institute for Advanced Materials and Nanotechnology
- Institute of Fundamental Sciences
- Massey University
- New Zealand
| | | | | | - Phimphaka Harding
- Functional Materials and Nanotechnology Center of Excellence
- Walailak University
- Thasala
- Thailand
| | - David J. Harding
- Functional Materials and Nanotechnology Center of Excellence
- Walailak University
- Thasala
- Thailand
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43
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44
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Wolny JA, Schünemann V, Németh Z, Vankó G. Spectroscopic techniques to characterize the spin state: Vibrational, optical, Mössbauer, NMR, and X-ray spectroscopy. CR CHIM 2018. [DOI: 10.1016/j.crci.2018.10.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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45
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Petzold H, Hörner G, Schnaubelt L, Rüffer T. Slow spin crossover in bis-meridional Fe 2+ complexes through spin-state auto-adaptive N6/N8 coordination. Dalton Trans 2018; 47:17257-17265. [PMID: 30488935 DOI: 10.1039/c8dt03652g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Fe2+ spin crossover (SCO) complexes with long-lived excited high-spin (HS) states are promising molecular switches. An enhanced kinetic stability of spin-state isomers can be expected to foster applications beyond the limits of cooperative SCO. In this study, we describe a new approach to slow down the spin-state exchange by simple commutation of a phenyl substituent by a pyridyl substituent. To this end, N4 ligand 6-(3-(pyridin-2-yl)-1H-pyrazol-1-yl)-2,2'-bipyridine (3b) is synthesized as an N4 homologue of the well-established meridional N3 ligands motif. Phenyl-substituted 6-(3-phenyl-1H-pyrazol-1-yl)-2,2'-bipyridine (3a) serves as an intrinsic N3 reference throughout. 3b offers variable coordination numbers, N3 versus N3(+1) and N4, reflecting the preferences of the metal center. As is shown herein through an extended solid-state structure-chemical and solution-state NMR study, which is augmented by density-functional theory modeling, both the coordination geometry and its structural dynamics are indeed highly sensitive towards the expansion of the nominal donor number. The additional donors in 3b introduced through the phenyl-pyridine commutation actually give rise to a rich and diverse stereochemistry of the derived Zn2+ and Fe2+ complexes. Notably, even within a single complex unit coordination of 3b ranges from strongly distorted N3 coordination with a long assisting additional contact (Zn2+ and Fe2+) to a more symmetric N2(+2) or N4 situation in Fe2+. DFT modeling unravels that the additional donors are hemi-labile and coordinate to the Fe2+ only in HS state, leaving the elusive low-spin (LS) state in a fairly undisturbed octahedral environment with 3b being N3 coordinate. That is, the coordination number of the complex autogeneously responds to the altered spin-state. Necessarily this switch in coordination number requires strong structural changes upon SCO. This leads to increased activation barriers for SCO as could be deduced from a temperature-dependent analysis of the dynamic 1H NMR-line broadening and corroborated by accompanying theoretical analysis of the SCO reaction coordinate. For [Fe(3b)2]2+ long spin-state lifetimes τ > 1 ms prevail below the characteristic temperature T (1 ms) = 235 K; this value should be compared with a lifetime of only 150 ns derived for the close analogue [Fe(3a)2]2+. The principle applied herein is general and allows transferring of LS Fe2+ complexes with suitably placed phenyl substituents into SCO complexes with spin-state adaptive coordination number and hence long-lived HS excited states.
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Affiliation(s)
- Holm Petzold
- TU Chemnitz, Institut für Chemie, Anorganische Chemie, Straße der Nationen 62, 09111 Chemnitz, Germany.
| | - Gerald Hörner
- TU Berlin, Institut für Chemie, Straße des 17. Juni 135, 10623 Berlin, Germany.
| | - Linda Schnaubelt
- TU Chemnitz, Institut für Chemie, Anorganische Chemie, Straße der Nationen 62, 09111 Chemnitz, Germany.
| | - Tobias Rüffer
- TU Chemnitz, Institut für Chemie, Anorganische Chemie, Straße der Nationen 62, 09111 Chemnitz, Germany.
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46
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Naim A, Bouhadja Y, Cortijo M, Duverger-Nédellec E, Flack HD, Freysz E, Guionneau P, Iazzolino A, Ould Hamouda A, Rosa P, Stefańczyk O, Valentín-Pérez Á, Zeggar M. Design and Study of Structural Linear and Nonlinear Optical Properties of Chiral [Fe(phen)3]2+ Complexes. Inorg Chem 2018; 57:14501-14512. [DOI: 10.1021/acs.inorgchem.8b01089] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Ahmad Naim
- ICMCB, CNRS, Université de Bordeaux, UMR 5026, F-33600 Pessac, France
| | - Yacine Bouhadja
- Department of Chemistry, University of Annaba, BP 12-23200 Sidi-Ammar, Algérie
| | - Miguel Cortijo
- ICMCB, CNRS, Université de Bordeaux, UMR 5026, F-33600 Pessac, France
- CRPP, CNRS, Université de Bordeaux, UMR 5031, F-33600 Pessac, France
| | | | - Howard D. Flack
- Chimie Minérale, Analytique et Appliquée, Sciences II, Université de Genève, 30, Quai Ernest-Ansermet CH-1211 Geneva Switzerland
| | - Eric Freysz
- LOMA, UMR CNRS 5798, 351 Cours de la Libération, FR-33405 Talence Cedex, France
| | | | - Antonio Iazzolino
- LOMA, UMR CNRS 5798, 351 Cours de la Libération, FR-33405 Talence Cedex, France
| | - Amine Ould Hamouda
- LOMA, UMR CNRS 5798, 351 Cours de la Libération, FR-33405 Talence Cedex, France
| | - Patrick Rosa
- ICMCB, CNRS, Université de Bordeaux, UMR 5026, F-33600 Pessac, France
| | - Olaf Stefańczyk
- ICMCB, CNRS, Université de Bordeaux, UMR 5026, F-33600 Pessac, France
| | - Ángela Valentín-Pérez
- ICMCB, CNRS, Université de Bordeaux, UMR 5026, F-33600 Pessac, France
- CRPP, CNRS, Université de Bordeaux, UMR 5031, F-33600 Pessac, France
| | - Mehdi Zeggar
- ICMCB, CNRS, Université de Bordeaux, UMR 5026, F-33600 Pessac, France
- Department of Chemistry, University of Annaba, BP 12-23200 Sidi-Ammar, Algérie
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47
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Sun Y, Pham AN, Waite TD. Mechanism Underlying the Effectiveness of Deferiprone in Alleviating Parkinson's Disease Symptoms. ACS Chem Neurosci 2018; 9:1118-1127. [PMID: 29381045 DOI: 10.1021/acschemneuro.7b00478] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Elevation in iron content as well as severe depletion of dopamine (DA) as a result of iron-induced loss of dopaminergic neurons has been recognized to accompany the progression of Parkinson's disease (PD). To better understand the mechanism of the mitigating effect of the iron chelator deferiprone (DFP) on PD, the interplay between iron and DFP was investigated both in the absence and presence of DA. The results show that DFP was extremely efficient in scavenging both aqueous iron and iron that was loosely bound to DA with the entrapment of iron in Fe-DFP complexed form critical to halting the iron catalyzed degradation of DA and associated generation of toxic metabolites. The DFP related scavenging of dopamine semiquinone (DA•-) and superoxide (O2•-) may also contribute to its positive effects in the treatment of PD.
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Affiliation(s)
- Yingying Sun
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
| | - An Ninh Pham
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
| | - T. David Waite
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
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48
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Scott HS, Staniland RW, Kruger PE. Spin crossover in homoleptic Fe(II) imidazolylimine complexes. Coord Chem Rev 2018. [DOI: 10.1016/j.ccr.2018.02.001] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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49
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Synthesis, crystal structures and high-temperature spin-crossover of new inclusion compounds of iron(II) tris (pyrazol-1-yl)methane complex with p -sulfonatocalix[4]arene. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2018.02.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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50
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Hrudka JJ, Phan H, Lengyel J, Rogachev AY, Shatruk M. Power of Three: Incremental Increase in the Ligand Field Strength of N-Alkylated 2,2′-Biimidazoles Leads to Spin Crossover in Homoleptic Tris-Chelated Fe(II) Complexes. Inorg Chem 2018; 57:5183-5193. [DOI: 10.1021/acs.inorgchem.8b00223] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Jeremy J. Hrudka
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, Florida 32306, United States
| | - Hoa Phan
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, Florida 32306, United States
| | - Jeff Lengyel
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, Florida 32306, United States
| | - Andrey Yu. Rogachev
- Department of Chemistry, Illinois Institute of Technology, 3101 South Dearborn St, Chicago, Illinois 60616, United States
| | - Michael Shatruk
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, Florida 32306, United States
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