1
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Juráková J, Santana VT, Pavlik J, Moncoľ J, Nemec I, Clemente-León M, Kuppusamy SK, Ruben M, Čižmár E, Šalitroš I. Magnetic anisotropy and slow relaxation of magnetisation in double salts containing four- and six-coordinate cobalt(II) complex ions. Dalton Trans 2024; 53:12962-12972. [PMID: 39026489 DOI: 10.1039/d4dt01509f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Four novel Co(II) coordination compounds 1-4 of the general formula [Co(Ln)2][Co(NCY)4]·mCH3CN (where Ln are tridentate ligands L1 = 2,6-bis(1-hexyl-1H-benzimidazol-2-yl)pyridine for 1 and 2; L2 = 2,6-bis(1-octyl-1H-benzimidazol-2-yl)pyridine for 3; L3 = 2,6-bis(1-dodecyl-1H-benzimidazol-2-yl)pyridine for 4, Y = O for 1, 3, and 4 and Y = S for 2; m = 0 for 1 and 3, m = 0.5 for 2 and m = 2 for 4) were prepared and characterised. The molecular structures of all four compounds consist of the hexacoordinate complex cation [Co(Ln)2]2+ and tetracoordinate complex anion [Co(NCY)4]2-, with distorted octahedral and tetrahedral symmetry of coordination polyhedra, respectively. The electronic structures of all compounds feature an orbitally non-degenerate ground state well-separated from the lowest excited state, which allows the analysis of the magnetic anisotropy by the spin Hamiltonian model. ZFS parameters, derived from both CASSCF-NEVPT2 calculations and magnetic data analysis, indicate that tetrahedral anions [Co(NCY)4]2- exhibit small axial parameters |D| spanning the range of 2.2 to 7.7 cm-1, while octahedral cations [Co(Ln)2]2+ display significantly larger |D| parameters in the range of 37 to 95 cm-1. For 1-3, the Fourier-transform infrared magnetic spectroscopy (FIRMS) revealed a reasonable transmission with a magnetic absorption around the expected value for the ZFS accompanied by features allowing to identify phonon frequencies and simulate spin-phonon couplings. Dynamic magnetic investigations unveiled the field-induced slow relaxation of magnetisation, with maximal relaxation times (τ) of 92(2) μs for 2 at 2 K and BDC = 0.3 T. The temperature evolution of τ was analysed using a combination of Orbach, direct and Raman relaxations (Ueff = 8(1) K (5.6 cm-1)) or Orbach, direct and spin-phonon induced relaxations (Ueff = 10.3(9) K (7.2 cm-1)). The rest of the complexes, namely 1, 3, and 4 show field-induced slow relaxation of magnetisation with τ smaller than 16 μs.
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Affiliation(s)
- Jana Juráková
- Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 61200 Brno, Czech Republic
- Department of Inorganic Chemistry, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Bratislava SK-81237, Slovakia.
| | - Vinicius Tadeu Santana
- Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 61200 Brno, Czech Republic
| | - Ján Pavlik
- Department of Inorganic Chemistry, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Bratislava SK-81237, Slovakia.
| | - Ján Moncoľ
- Department of Inorganic Chemistry, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Bratislava SK-81237, Slovakia.
| | - Ivan Nemec
- Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 61200 Brno, Czech Republic
- Department of Inorganic Chemistry, Faculty of Science, Palacký University, 17. listopadu 12, 771 46 Olomouc, Czech Republic
| | - Miguel Clemente-León
- Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, Catedrático José Beltrán 2, 46980 Paterna, Spain
| | - Senthil Kumar Kuppusamy
- Institute of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Mario Ruben
- Institute of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Erik Čižmár
- Institute of Physics, Faculty of Science, P.J. Šafárik University, Park Angelinum 9, 04154 Košice, Slovakia
| | - Ivan Šalitroš
- Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 61200 Brno, Czech Republic
- Department of Inorganic Chemistry, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Bratislava SK-81237, Slovakia.
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Rabelo R, Toma L, Julve M, Lloret F, Pasán J, Cangussu D, Ruiz-García R, Cano J. How the spin state tunes the slow magnetic relaxation field dependence in spin crossover cobalt(II) complexes. Dalton Trans 2024; 53:5507-5520. [PMID: 38416047 DOI: 10.1039/d4dt00059e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
A novel family of cobalt(II) compounds with tridentate pyridine-2,6-diiminephenyl type ligands featuring electron-withdrawing substituents of general formula [Co(n-XPhPDI)2](ClO4)2·S [n-XPhPDI = 2,6-bis(N-n-halophenylformimidoyl)pyridine with n = 4 (1-3) and 3 (4); X = I (1), Br (2 and 4) and Cl (3); S = MeCN (1 and 2) and EtOAc (3)] has been synthesised and characterised by single-crystal X-ray diffraction, electron paramagnetic resonance, and static (dc) and dynamic (ac) magnetic measurements combined with theoretical calculations. The structures of 1-4 consist of mononuclear bis(chelating) cobalt(II) complex cations, [CoII(n-XPhPDI)2]2+, perchlorate anions, and acetonitrile (1 and 2) or ethyl acetate (3) molecules of crystallisation. This unique series of mononuclear six-coordinate octahedral cobalt(II) complexes displays both thermally-induced low-spin (LS)/high-spin (HS) transition and field-induced slow magnetic relaxation in both LS and HS states. A complete LS ↔ HS transition occurs for 1 and 2, while it is incomplete for 4, one-third of the complexes being HS at low temperatures. In contrast, 3 remains HS in all the temperature range. 1 and 2 show dual spin relaxation dynamics under the presence of an applied dc magnetic field (Hdc), with the occurrence of faster- (FR) and slower-relaxing (SR) processes at lower (Hdc = 1.0 kOe) and higher fields (Hdc = 2.5 kOe), respectively. On the contrary, 3 and 4 exhibit only SR and FR relaxations, regardless of Hdc. Overall, the distinct field-dependence of the single-molecule magnet (SMM) behaviour along with this family of spin-crossover (SCO) cobalt(II)-n-XPhPDI complexes is dominated by Raman mechanisms and, occasionally, with additional temperature-independent Intra-Kramer [LS or HS (D > 0)] or Quantum Tunneling of Magnetisation mechanisms [HS (D < 0)] also contributing.
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Affiliation(s)
- Renato Rabelo
- Instituto de Ciencia Molecular (ICMol), Universitat de València, 46980 Paterna, València, Spain.
- Instituto de Química, Universidade Federal de Goiás, Av. Esperança Campus Samambaia, Goiânia, GO, Brazil
| | - Luminita Toma
- Instituto de Ciencia Molecular (ICMol), Universitat de València, 46980 Paterna, València, Spain.
| | - Miguel Julve
- Instituto de Ciencia Molecular (ICMol), Universitat de València, 46980 Paterna, València, Spain.
| | - Francesc Lloret
- Instituto de Ciencia Molecular (ICMol), Universitat de València, 46980 Paterna, València, Spain.
| | - Jorge Pasán
- Laboratorio de Materiales para Análisis Químico (MAT4LL), Departamento de Química, Facultad de Ciencias, Universidad de La Laguna, 38200 Tenerife, Spain
| | - Danielle Cangussu
- Instituto de Química, Universidade Federal de Goiás, Av. Esperança Campus Samambaia, Goiânia, GO, Brazil
| | - Rafael Ruiz-García
- Instituto de Ciencia Molecular (ICMol), Universitat de València, 46980 Paterna, València, Spain.
| | - Joan Cano
- Instituto de Ciencia Molecular (ICMol), Universitat de València, 46980 Paterna, València, Spain.
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Choroba K, Palion-Gazda J, Machura B, Bieńko A, Wojtala D, Bieńko D, Rajnák C, Boča R, Ozarowski A, Ozerov M. Large Magnetic Anisotropy in Mono- and Binuclear cobalt(II) Complexes: The Role of the Distortion of the Coordination Sphere in Validity of the Spin-Hamiltonian Formalism. Inorg Chem 2024; 63:1068-1082. [PMID: 38166196 DOI: 10.1021/acs.inorgchem.3c03405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2024]
Abstract
To get a better insight into understanding the factors affecting the enhancement of the magnetic anisotropy in single molecule (single ion) magnets, two cobalt(II) complexes based on a tridentate ligand 2,6-di(thiazol-2-yl)pyridine substituted at the 4-position with N-methyl-pyrrol-2-yl have been synthesized and studied by X-ray crystallography, AC and DC magnetic data, FIRMS and HFEPR spectra, and theoretical calculations. The change of the counteranion in starting Co(II) salts results in the formation of pentacoordinated mononuclear [Co(mpyr-dtpy)Cl2]·2MeCN (1) complex and binuclear [Co(mpyr-dtpy)2][Co(NCS)4] (2) compound. The observed marked distortion of trigonal bipyramid geometry in 1 and cationic octahedral and anionic tetrahedral units in 2 brings up a question about the validity of the spin-Hamiltonian formalism and the possibility of determining the value and sign of the zero-field splitting D parameter. Both complexes exhibit field-induced slow magnetic relaxation with two or three relaxation channels at BDC = 0.3 T. The high-frequency relaxation time in the reciprocal form τ(HF)-1 = CTn develops according to the Raman relaxation mechanism (for 2, n = 8.8) and the phonon-bottleneck-like mechanism (for 1, n = 2.3). The high-frequency relaxation time at T = 2.0 K and BDC = 0.30 T is τ(HF) = 96 and 47 μs for 1 and 2, respectively.
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Affiliation(s)
- Katarzyna Choroba
- Institute of Chemistry, Faculty of Science and Technology, University of Silesia, Szkolna St. 9, Katowice 40-006, Poland
| | - Joanna Palion-Gazda
- Institute of Chemistry, Faculty of Science and Technology, University of Silesia, Szkolna St. 9, Katowice 40-006, Poland
| | - Barbara Machura
- Institute of Chemistry, Faculty of Science and Technology, University of Silesia, Szkolna St. 9, Katowice 40-006, Poland
| | - Alina Bieńko
- Faculty of Chemistry, Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Daria Wojtala
- Faculty of Chemistry, Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Dariusz Bieńko
- Faculty of Chemistry, Wroclaw University of Science Technology, Wybrzeze Wyspiańskiego 27, Wroclaw 50-370, Poland
| | - Cyril Rajnák
- Faculty of Health Science and Faculty of Natural Sciences, University of SS Cyril and Methodius, Trnava SK-917 01, Slovakia
| | - Roman Boča
- Institute of Chemistry, Faculty of Science and Technology, University of Silesia, Szkolna St. 9, Katowice 40-006, Poland
| | - Andrew Ozarowski
- National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, Florida 32310, United States
| | - Mykhaylo Ozerov
- National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, Florida 32310, United States
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Ghosh S, Ghosh S, Kamilya S, Mandal S, Mehta S, Mondal A. Impact of Counteranion on Reversible Spin-State Switching in a Series of Cobalt(II) Complexes Containing a Redox-Active Ethylenedioxythiophene-Based Terpyridine Ligand. Inorg Chem 2022; 61:17080-17088. [PMID: 36264687 DOI: 10.1021/acs.inorgchem.2c02313] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The self-assembly of a redox-active ethylenedioxythiophene (EDOT)-terpyridine-based tridentate ligand and cobalt(II) unit with different counteranions has led to a series of new cobalt(II) complexes [Co(L)2](X)2 (X = BF4 (1), ClO4 (2), and BPh4 (3)) (L = 4'-(3,4-ethylenedioxythiophene)-2,2':6',2″-terpyridine). The impact of various counteranions on stabilization and spin-state switching of the cobalt(II) center was explored through detailed magneto-structural investigation using variable temperature single-crystal X-ray diffraction, magnetic, spectroscopic, electrochemical, and spectroelectrochemical studies. All three complexes 1-3 consisted of an isostructural dicationic distorted octahedral CoN6 coordination environment offered by the two L ligands in a bis-meridional fashion and BF4-, ClO4-, and BPh4- as a counteranion, respectively. Complex 2 with ClO4- counteranion showed a reversible, gradual, and nearly complete spin-state switching between low-spin (LS) (S = 1/2) and high-spin (HS) (S = 3/2) states, while an incomplete spin-state switching behavior was observed for complexes 1 (BF4-) and 3 (BPh4-) in the measured temperature range of 350-2 K. The non-covalent cation-anion interactions played a significant role in stabilizing the spin-state in 1-3. Additionally, complexes 1-3 also exhibited interesting redox-stimuli-based reversible paramagnetic HS cobalt(II) (S = 3/2) to diamagnetic LS cobalt(III) (S = 0) conversion, offering an alternate way to switch the magnetic properties.
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Affiliation(s)
- Subrata Ghosh
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C V Raman Road, Bangalore 560012, India
| | - Sounak Ghosh
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C V Raman Road, Bangalore 560012, India
| | - Sujit Kamilya
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C V Raman Road, Bangalore 560012, India
| | - Subhankar Mandal
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C V Raman Road, Bangalore 560012, India
| | - Sakshi Mehta
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C V Raman Road, Bangalore 560012, India
| | - Abhishake Mondal
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C V Raman Road, Bangalore 560012, India
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5
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Monitoring the Substrate‐Induced Spin‐State Distribution in a Cobalt(II)‐Salen Complex by EPR and DFT. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202101071] [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]
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6
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Steric Quenching of Mn(III) Thermal Spin Crossover: Dilution of Spin Centers in Immobilized Solutions. MAGNETOCHEMISTRY 2022. [DOI: 10.3390/magnetochemistry8010008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Structural and magnetic properties of a new spin crossover complex [Mn(4,6-diOMe-sal2323)]+ in lattices with ClO4−, (1), NO3−, (2), BF4−, (3), CF3SO3−, (4), and Cl− (5) counterions are reported. Comparison with the magnetostructural properties of the C6, C12, C18 and C22 alkylated analogues of the ClO4− salt of [Mn(4,6-diOMe-sal2323)]+ demonstrates that alkylation effectively switches off the thermal spin crossover pathway and the amphiphilic complexes are all high spin. The spin crossover quenching in the amphiphiles is further probed by magnetic, structural and Raman spectroscopic studies of the PF6− salts of the C6, C12 and C18 complexes of a related complex [Mn(3-OMe-sal2323)]+ which confirm a preference for the high spin state in all cases. Structural analysis is used to rationalize the choice of the spin quintet form in the seven amphiphilic complexes and to highlight the non-accessibility of the smaller spin triplet form of the ion more generally in dilute environments. We suggest that lattice pressure is a requirement to stabilize the spin triplet form of Mn3+ as the low spin form is not known to exist in solution.
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Huang YL, Zhong YJ, Ye HJ, Li YH, Kuang XM, Ouyang ZJ, Chen WB, Yang M, Dong W. Slow magnetic relaxation and spin crossover behavior in two mixed-valence Co( ii)/Co( iii) complexes. NEW J CHEM 2022. [DOI: 10.1039/d2nj03051a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two mixed-valence Co(ii)/Co(iii) complexes of [CoII(phen)3][CoIII(HATD)2]2·3DMA·3.5H2O (1) with field induced single-molecule magnet behavior, and [CoII(terpy)2][CoIII(HATD)2]2·4DMA·H2O (2) with a gradual thermal spin crossover (SCO).
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Affiliation(s)
- You-Lin Huang
- Guangzhou Key Laboratory for Environmentally Functional Materials and Technology, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
| | - Yun-Jing Zhong
- Guangzhou Key Laboratory for Environmentally Functional Materials and Technology, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
| | - Hua-Jian Ye
- Guangzhou Key Laboratory for Environmentally Functional Materials and Technology, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
| | - You-Hong Li
- Guangzhou Key Laboratory for Environmentally Functional Materials and Technology, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
| | - Xiao-Man Kuang
- Guangzhou Key Laboratory for Environmentally Functional Materials and Technology, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
| | - Zhi-Jian Ouyang
- Guangzhou Key Laboratory for Environmentally Functional Materials and Technology, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
| | - Wen-Bin Chen
- Guangzhou Key Laboratory for Environmentally Functional Materials and Technology, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
| | - Meng Yang
- Guangzhou Key Laboratory for Environmentally Functional Materials and Technology, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
| | - Wen Dong
- Guangzhou Key Laboratory for Environmentally Functional Materials and Technology, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
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Gharbi C, Fujita W, Lefebvre F, Kaminsky W, Jelsch C, Nasr CB, Khedhiri L. Synthesis, crystal structure, computational studies and spectroscopic characterization of a hybrid material self-assembly from tetra(isothiocyanate)cobalt(II) anion and 1-(4-methoxyphenyl)piperazinium. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2021.129929] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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9
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Świtlicka A, Machura B, Cano J, Lloret F, Julve M. A Study of the Lack of Slow Magnetic Relaxation in Mononuclear Trigonal Bipyramidal Cobalt(II) Complexes. ChemistrySelect 2021. [DOI: 10.1002/slct.202100061] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Anna Świtlicka
- Department Of Crystallography, Institute of Chemistry University of Silesia 9th Szkolna St., 40–006 Katowice Poland
| | - Barbara Machura
- Department Of Crystallography, Institute of Chemistry University of Silesia 9th Szkolna St., 40–006 Katowice Poland
| | - Joan Cano
- Department of Química Inorgànica/Instituto de Ciencia Molecular (ICMol) Facultat de Quimica de la Universitat de València C/ Catedrático Jose Beltrán 2 46980 Paterna, València Spain
| | - Francesc Lloret
- Department of Química Inorgànica/Instituto de Ciencia Molecular (ICMol) Facultat de Quimica de la Universitat de València C/ Catedrático Jose Beltrán 2 46980 Paterna, València Spain
| | - Miguel Julve
- Department of Química Inorgànica/Instituto de Ciencia Molecular (ICMol) Facultat de Quimica de la Universitat de València C/ Catedrático Jose Beltrán 2 46980 Paterna, València Spain
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Chen SY, Lv W, Cui HH, Chen L, Zhang YQ, Chen XT, Wang Z, Ouyang ZW, Yan H, Xue ZL. Magnetic anisotropies and slow magnetic relaxation of three tetrahedral tetrakis(pseudohalido)–cobalt( ii) complexes. NEW J CHEM 2021. [DOI: 10.1039/d1nj01916c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Magnetic anisotropies and slow magnetic relaxation of three homoleptic cobalt(ii) complexes with different pseudohalide ligands were studied via magnetometry, HFEPR and theoretical calculations.
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Affiliation(s)
- Shu-Yang Chen
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Wei Lv
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Hui-Hui Cui
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Lei Chen
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China
| | - Yi-Quan Zhang
- Jiangsu Key Laboratory for NSLSCS, School of Physical Science and Technology, Nanjing Normal University, Nanjing 210023, China
| | - Xue-Tai Chen
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Zhenxing Wang
- Wuhan National High Magnetic Field Center & School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Zhong-Wen Ouyang
- Wuhan National High Magnetic Field Center & School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Hong Yan
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Zi-Ling Xue
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee, 37996, USA
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11
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Kühne IA, Esien K, Gavin LC, Müller-Bunz H, Felton S, Morgan GG. Modulation of Mn 3+ Spin State by Guest Molecule Inclusion. Molecules 2020; 25:E5603. [PMID: 33260579 PMCID: PMC7730159 DOI: 10.3390/molecules25235603] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 11/25/2020] [Accepted: 11/26/2020] [Indexed: 11/29/2022] Open
Abstract
Spin state preferences for a cationic Mn3+ chelate complex in four different crystal lattices are investigated by crystallography and SQUID magnetometry. The [MnL1]+ complex cation was prepared by complexation of Mn3+ to the Schiff base chelate formed from condensation of 4-methoxysalicylaldehyde and 1,2-bis(3-aminopropylamino)ethane. The cation was crystallized separately with three polyatomic counterions and in one case was found to cocrystallize with a percentage of unreacted 4-methoxysalicylaldehyde starting material. The spin state preferences of the four resultant complexes [MnL1]CF3SO3·xH2O, (1), [MnL1]PF6·xH2O, (2), [MnL1]PF6·xsal·xH2O, (2b), and [MnL1]BPh4, (3), were dependent on their ability to form strong intermolecular interactions. Complexes (1) and (2), which formed hydrogen bonds between [MnL1]+, lattice water and in one case also with counterion, showed an incomplete thermal spin crossover over the temperature range 5-300 K. In contrast, complex (3) with the BPh4-, counterion and no lattice water, was locked into the high spin state over the same temperature range, as was complex (2b), where inclusion of the 4-methoxysalicylaldehyde guest blocked the H-bonding interaction.
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Affiliation(s)
- Irina A. Kühne
- School of Chemistry, University College Dublin (UCD), Belfield, D04 V1W8 Dublin, Ireland; (I.A.K.); (L.C.G.); (H.M.-B.)
| | - Kane Esien
- School of Mathematics and Physics, Queen’s University Belfast, Belfast BT7 1NN, UK; (K.E.); (S.F.)
| | - Laurence C. Gavin
- School of Chemistry, University College Dublin (UCD), Belfield, D04 V1W8 Dublin, Ireland; (I.A.K.); (L.C.G.); (H.M.-B.)
| | - Helge Müller-Bunz
- School of Chemistry, University College Dublin (UCD), Belfield, D04 V1W8 Dublin, Ireland; (I.A.K.); (L.C.G.); (H.M.-B.)
| | - Solveig Felton
- School of Mathematics and Physics, Queen’s University Belfast, Belfast BT7 1NN, UK; (K.E.); (S.F.)
| | - Grace G. Morgan
- School of Chemistry, University College Dublin (UCD), Belfield, D04 V1W8 Dublin, Ireland; (I.A.K.); (L.C.G.); (H.M.-B.)
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12
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New binuclear Hg(II)-2,3,5,6-tetrakis-(2-pyridyl)pyrazine complexes: Synthesis, characterization, luminescence study and crystal structure determination. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2019.127324] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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13
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Ghosh S, Selvamani S, Mehta S, Mondal A. Reversible thermo-induced spin crossover in a mononuclear cis-dicyanamido-cobalt(ii) complex containing a macrocyclic tetradentate ligand. Dalton Trans 2020; 49:9208-9212. [DOI: 10.1039/d0dt01888k] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
For the first time, a mononuclear cobalt(ii) complex with dicyanamide coligands exhibiting reversible spin crossover behavior at high temperature is reported.
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Affiliation(s)
- Subrata Ghosh
- Solid State and Structural Chemistry Unit
- Indian Institute of Science
- Bangalore 560012
- India
| | - Subramani Selvamani
- Solid State and Structural Chemistry Unit
- Indian Institute of Science
- Bangalore 560012
- India
| | - Sakshi Mehta
- Solid State and Structural Chemistry Unit
- Indian Institute of Science
- Bangalore 560012
- India
| | - Abhishake Mondal
- Solid State and Structural Chemistry Unit
- Indian Institute of Science
- Bangalore 560012
- India
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14
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Świtlicka A, Machura B, Penkala M, Bieńko A, Bieńko DC, Titiš J, Rajnák C, Boča R, Ozarowski A. Slow magnetic relaxation in hexacoordinated cobalt(ii) field-induced single-ion magnets. Inorg Chem Front 2020. [DOI: 10.1039/d0qi00257g] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To gain an insight into the factors affecting the enhancement of the energy barrier in SMM/SIM, hexacoordinate pseudohalide Co(ii) complexes based on the tridentate ligand were investigated.
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Affiliation(s)
- Anna Świtlicka
- Department of Crystallography
- Institute of Chemistry
- University of Silesia
- 40-006 Katowice
- Poland
| | - Barbara Machura
- Department of Crystallography
- Institute of Chemistry
- University of Silesia
- 40-006 Katowice
- Poland
| | - Mateusz Penkala
- Department of Inorganic
- Organometallic Chemistry and Catalysis
- Institute of Chemistry
- University of Silesia
- 40-006 Katowice
| | - Alina Bieńko
- Faculty of Chemistry
- University of Wroclaw
- 50-383 Wroclaw
- Poland
| | - Dariusz C. Bieńko
- Faculty of Chemistry
- Wroclaw University of Technology
- 50-370 Wroclaw
- Poland
| | - Ján Titiš
- Department of Chemistry
- Faculty of Natural Sciences
- University of SS Cyril and Methodius
- 917 01 Trnava
- Slovakia
| | - Cyril Rajnák
- Department of Chemistry
- Faculty of Natural Sciences
- University of SS Cyril and Methodius
- 917 01 Trnava
- Slovakia
| | - Roman Boča
- Department of Chemistry
- Faculty of Natural Sciences
- University of SS Cyril and Methodius
- 917 01 Trnava
- Slovakia
| | - Andrew Ozarowski
- National High Magnetic Field Laboratory
- Florida State University
- Tallahassee
- USA
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15
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Ghosh S, Selvamani S, Kamilya S, Mehta S, Mondal A. Tuning of Spin Crossover Properties in a Series of Mononuclear Cobalt(II) Complexes Based on Macrocyclic Tetradentate Ligand and Pseudohalide Coligands. Dalton Trans 2020; 51:9642-9652. [DOI: 10.1039/d0dt02546a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The three mononuclear cobalt(II) complexes, [Co(L)(NCX)2] (L = N,N'-di-tert-butyl-2,11-diaza[3,3](2,6)pyridinophane, and X = S (1), Se (2), and [C(CN)2] (3)), have been synthesized and characterized using variable temperature single-crystal X-ray crystallography,...
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16
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Zhao FH, Jia XM, He YC, Huang LW, Yan XQ, Li ZL, Li JX, Feng R, You JM. Syntheses and magnetic properties of three transition metal complexes based on 4′-p-tolyl-2,2′:6′,2″-terpyridine and SCN−. Polyhedron 2019. [DOI: 10.1016/j.poly.2019.114124] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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17
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Yang L, Zhou J, Zou HH, Tang Q. Three new metal coordination polymers of bifunctional imidazolate/tetrazolate bridges: the only example of a three-dimensional framework based on rare [Co 4(μ 3-OH) 2(μ 2-Cl) 2] 4+ mixed oxo-chloro-clusters. RSC Adv 2019; 9:13082-13087. [PMID: 35520796 PMCID: PMC9063806 DOI: 10.1039/c9ra01327j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 04/23/2019] [Indexed: 11/21/2022] Open
Abstract
Three new metal coordination polymers [Ni(μ2-L)2(H2O)2] n (1, HL = 1-tetrazole-4-imidazole-benzene), [Co(μ2-L)2] n (2), and [Co4(μ3-OH)2(μ2-Cl)2(μ5-L)2(μ2-L)2] n ·7nH2O (3) were hydrothermally synthesized and structurally characterized. 1 displays a neutral [Ni(μ2-L)2(H2O)2] n chain built up from the Ni2+ ions bridged by deprotonated L- ligands, while 2 shows another rare neutral [Co(μ2-L)2] n chain based on Co2+ ions connected by two different coordination modes of the L- ligand. 3 exhibits a rare [Co4(μ3-OH)2(μ2-Cl)2]4+ mixed oxo-chloro-cluster-based three-dimensional framework with large elliptical channels, which are filled by unprecedented chilopod [(H2O)7] n chains. Both 1 and 2 show antiferromagnetic behavior, while 3 exhibits unusual spin-canting.
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Affiliation(s)
- Lili Yang
- Chongqing Key Laboratory of Inorganic Functional Materials, College of Chemistry, Chongqing Normal University Chongqing 401331 P. R. China
| | - Jian Zhou
- Chongqing Key Laboratory of Inorganic Functional Materials, College of Chemistry, Chongqing Normal University Chongqing 401331 P. R. China
| | - Hua-Hong Zou
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry & Pharmacy of Guangxi Normal University Guilin 541004 P. R. China
| | - Qiuling Tang
- Chongqing Key Laboratory of Inorganic Functional Materials, College of Chemistry, Chongqing Normal University Chongqing 401331 P. R. China
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18
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Xie Y. Electrochemical Performance of Transition Metal‐Coordinated Polypyrrole: A Mini Review. CHEM REC 2019; 19:2370-2384. [DOI: 10.1002/tcr.201800192] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 02/20/2019] [Accepted: 02/24/2019] [Indexed: 01/21/2023]
Affiliation(s)
- Yibing Xie
- School of Chemistry and Chemical EngineeringSoutheast University Nanjing 211189 China
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19
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Świtlicka A, Palion-Gazda J, Machura B, Cano J, Lloret F, Julve M. Field-induced slow magnetic relaxation in pseudooctahedral cobalt(ii) complexes with positive axial and large rhombic anisotropy. Dalton Trans 2019; 48:1404-1417. [DOI: 10.1039/c8dt03965h] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The preparation, X-ray crystal structure, spectroscopic and variable-temperature dc and ac magnetic properties of two six-coordinate cobalt(ii) complexes of formula [Co(bim)4(tcm)2] (1) and [Co(bmim)4(tcm)2] (2) are reported.
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Affiliation(s)
- Anna Świtlicka
- Department of Crystallography
- Institute of Chemistry
- University of Silesia
- 40-006 Katowice
- Poland
| | - Joanna Palion-Gazda
- Department of Crystallography
- Institute of Chemistry
- University of Silesia
- 40-006 Katowice
- Poland
| | - Barbara Machura
- Department of Crystallography
- Institute of Chemistry
- University of Silesia
- 40-006 Katowice
- Poland
| | - Joan Cano
- Department of Química Inorgànica/Instituto de Ciencia Molecular (ICMol)
- Facultat de Quimica de la Universitat de València
- 46980 Paterna
- Spain
- Fundació General de la Universitat de València (FGUV)
| | - Francesc Lloret
- Department of Química Inorgànica/Instituto de Ciencia Molecular (ICMol)
- Facultat de Quimica de la Universitat de València
- 46980 Paterna
- Spain
| | - Miguel Julve
- Department of Química Inorgànica/Instituto de Ciencia Molecular (ICMol)
- Facultat de Quimica de la Universitat de València
- 46980 Paterna
- Spain
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20
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Roy M, Adhikary A, Mondal AK, Mondal R. Multifunctional Properties of a 1D Helical Co(II) Coordination Polymer: Toward Single-Ion Magnetic Behavior and Efficient Dye Degradation. ACS OMEGA 2018; 3:15315-15324. [PMID: 31458193 PMCID: PMC6644332 DOI: 10.1021/acsomega.8b02212] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 10/31/2018] [Indexed: 05/16/2023]
Abstract
This contribution deals with the synthesis and utilization of a new pyrazole-based unsymmetrical ligand, 3-(3-carboxyphenyl)-1H-pyrazole-5-carboxylic acid (H2CPCA), for generating multifunctional materials. The reaction with the Co(II) salt in the presence of a co-ligand 2,9-dimethyl phenanthroline (dmphen) results in the formation of the helical compound {[Co2(dmphen)2(CPCA)2]DMF} n (1). However, two isostructural monomeric complexes are formed {[M(HCPCA)2(H2O)2], M = Co(II), (2) and Mn(II) (3)} when reactions were carried out in the absence of dmphen. Compound 1 shows some highly encouraging single-ion magnetic (SIM) properties. Detailed magnetic studies unveil slow relaxation of magnetization of compound 1, driven by the higher magnetic anisotropy of the cobalt ion, with the energy barrier of ∼9.2 K and relaxation time of 9.1 × 10-5 s, suggesting a SIM behavior. Moreover, UV-vis and fluorescence studies confirm the selective dye degradation of compound 1 with methylene blue both in the presence and absence of H2O2, with the remarkable degradation efficiency of ∼98 and ∼82%, respectively.
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Affiliation(s)
- Manasi Roy
- School
of Chemical Sciences, Indian Association
for the Cultivation of Science, 2A & 2B, Raja S.C. Mullick Road, Kolkata 700032, West Bengal, India
| | - Amit Adhikary
- School
of Chemical Sciences, Indian Association
for the Cultivation of Science, 2A & 2B, Raja S.C. Mullick Road, Kolkata 700032, West Bengal, India
- E-mail: (A.A.)
| | - Amit Kumar Mondal
- Department
of Chemical and Biological Physics, Weizmann
Institute of Science, 234 Herzl Street, P.O. Box 26, Rehovot 7610001, Israel
| | - Raju Mondal
- School
of Chemical Sciences, Indian Association
for the Cultivation of Science, 2A & 2B, Raja S.C. Mullick Road, Kolkata 700032, West Bengal, India
- E-mail: (R.M.)
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21
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Chen L, Song J, Zhao W, Yi G, Zhou Z, Yuan A, Song Y, Wang Z, Ouyang ZW. A mononuclear five-coordinate Co(ii) single molecule magnet with a spin crossover between the S = 1/2 and 3/2 states. Dalton Trans 2018; 47:16596-16602. [PMID: 30417917 DOI: 10.1039/c8dt03783c] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Although a great number of single-ion magnets (SIMs) and spin-crossover (SCO) compounds have been discovered, multifunctional materials with the combination of SCO and SIM properties are extremely scarce. Here magnetic studies have been carried out for a mononuclear, five-coordinate cobalt(ii) complex [Co(3,4-lut)4Br]Br (1) with square pyramidal geometry. Direct-current magnetic measurement confirms the spin transition between the S = 1/2 and 3/2 states in the range of 150-290 K with a small hysteresis loop. Frequency- and temperature-dependent alternating-current magnetic susceptibility reveals slow magnetization relaxation under an applied dc field of 3000 Oe. The work here presents the first instance of the five-coordinate mononuclear cobalt(ii)-based SIM exhibiting the thermally induced complete SCO.
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Affiliation(s)
- Lei Chen
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, P. R. China.
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22
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23
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Burrows KE, Kulmaczewski R, Cespedes O, Barrett SA, Halcrow MA. The speciation of homochiral and heterochiral diastereomers of homoleptic cobalt(II) and zinc(II) PyBox complexes. Polyhedron 2018. [DOI: 10.1016/j.poly.2018.04.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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24
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Ma X, Suturina EA, De S, Négrier P, Rouzières M, Clérac R, Dechambenoit P. A Redox-Active Bridging Ligand to Promote Spin Delocalization, High-Spin Complexes, and Magnetic Multi-Switchability. Angew Chem Int Ed Engl 2018; 57:7841-7845. [PMID: 29714814 DOI: 10.1002/anie.201803842] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Indexed: 11/08/2022]
Abstract
A dinuclear CoII complex, [Co2 (tphz)(tpy)2 ]n+ (n=4, 3 or 2; tphz: tetrapyridophenazine; tpy: terpyridine), has been assembled using the redox-active and strongly complexing tphz bridging ligand. The magnetic properties of this complex can be tuned from spin-crossover with T1/2 ≈470 K for the pristine compound (n=4) to single-molecule magnet with an ST =5/2 spin ground state when once reduced (n=3) to finally a diamagnetic species when twice reduced (n=2). The two successive and reversible reductions are concomitant with an increase of the spin delocalization within the complex, promoting remarkably large magnetic exchange couplings and high-spin species even at room temperature.
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Affiliation(s)
- Xiaozhou Ma
- CNRS, CRPP, UMR 5031, 33600, Pessac, France.,Univ. Bordeaux, CRPP, UMR 5031, 33600, Pessac, France
| | - Elizaveta A Suturina
- School of Chemistry, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK
| | - Siddhartha De
- CNRS, CRPP, UMR 5031, 33600, Pessac, France.,Univ. Bordeaux, CRPP, UMR 5031, 33600, Pessac, France
| | - Philippe Négrier
- CNRS, LOMA, UMR 5798, 33400, Talence, France.,Univ. Bordeaux, LOMA, UMR 5798, 33400, Talence, France
| | - Mathieu Rouzières
- CNRS, CRPP, UMR 5031, 33600, Pessac, France.,Univ. Bordeaux, CRPP, UMR 5031, 33600, Pessac, France
| | - Rodolphe Clérac
- CNRS, CRPP, UMR 5031, 33600, Pessac, France.,Univ. Bordeaux, CRPP, UMR 5031, 33600, Pessac, France
| | - Pierre Dechambenoit
- CNRS, CRPP, UMR 5031, 33600, Pessac, France.,Univ. Bordeaux, CRPP, UMR 5031, 33600, Pessac, France
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25
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Ma X, Suturina EA, De S, Négrier P, Rouzières M, Clérac R, Dechambenoit P. A Redox-Active Bridging Ligand to Promote Spin Delocalization, High-Spin Complexes, and Magnetic Multi-Switchability. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201803842] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Xiaozhou Ma
- CNRS; CRPP, UMR 5031; 33600 Pessac France
- Univ. Bordeaux; CRPP, UMR 5031; 33600 Pessac France
| | - Elizaveta A. Suturina
- School of Chemistry; University of Southampton; Highfield Campus Southampton SO17 1BJ UK
| | - Siddhartha De
- CNRS; CRPP, UMR 5031; 33600 Pessac France
- Univ. Bordeaux; CRPP, UMR 5031; 33600 Pessac France
| | - Philippe Négrier
- CNRS; LOMA, UMR 5798; 33400 Talence France
- Univ. Bordeaux; LOMA, UMR 5798; 33400 Talence France
| | - Mathieu Rouzières
- CNRS; CRPP, UMR 5031; 33600 Pessac France
- Univ. Bordeaux; CRPP, UMR 5031; 33600 Pessac France
| | - Rodolphe Clérac
- CNRS; CRPP, UMR 5031; 33600 Pessac France
- Univ. Bordeaux; CRPP, UMR 5031; 33600 Pessac France
| | - Pierre Dechambenoit
- CNRS; CRPP, UMR 5031; 33600 Pessac France
- Univ. Bordeaux; CRPP, UMR 5031; 33600 Pessac France
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26
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Switlicka A, Machura B, Kruszynski R, Cano J, Toma LM, Lloret F, Julve M. The influence of pseudohalide ligands on the SIM behaviour of four-coordinate benzylimidazole-containing cobalt(ii) complexes. Dalton Trans 2018; 47:5831-5842. [PMID: 29648565 DOI: 10.1039/c7dt04735e] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Three, mononuclear complexes of the formula [Co(bmim)2(SCN)2] (1), [Co(bmim)2(NCO)2] (2) and [Co(bmim)2(N3)2] (3) [bmim = 1-benzyl-2-methylimidazole] were prepared and structurally analyzed by single-crystal X-ray crystallography. The cobalt(ii) ions in 1-3 are tetrahedrally coordinated with two bmim molecules and two pseudohalide anions. The angular distortion parameter δ was calculated and the SHAPE program (based on the CShM concept) was used for 1-3 to estimate the angular distortion from an ideal tetrahedron. The molecules of 1-3 are effectively separated, and the values of the shortest distance of cobalt-cobalt are 8.442(6) and 6.774(8) Å for 1, 10.349(8) and 10.716(8) Å for 2 and 6.778(1) and 9.232(1) Å for 3. Direct current (dc) magnetic susceptibility measurements on the crushed crystals of 1-3 were carried out in the temperature range 1.9-295 K. The variable-temperature magnetic data of 1-3 mainly obey the zero-field splitting effect (D) of the 4A2 ground term of the tetrahedral cobalt(ii) complexes (2D being the energy gap between the |±1/2 and |±3/2 levels of the spin). The analysis of their magnetic data through the Hamiltonian H = D[S2z - S(S + 1)/3] + E(Sx2 - Sy2) + gβHS led to the following best-fit parameters: g = 2.29, D = -7.5 cm-1 and E/D = 0.106 (1), g = 2.28, D = + 6.3 cm-1 and E/D = 0.007 (2) and g = 2.36, D = + 6.7 cm-1 and E/D = 0.090 (3). The signs of D for 1-3 were confirmed by Q-band EPR spectra on powdered samples in the temperature range 4.0-20 K. Field-induced SIM behaviour was observed for 1-3 below 4.0 K, and the frequency-dependent maxima of χ''M were observed for 1 and only incipient signals of χ''M occurred for 2 and 3. The values of the exponential factor (τ0) and activation energy (Ea) for 1-3 which were obtained from the Arrhenius plot suggest a single relaxation process characteristic of an Orbach mechanism.
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Affiliation(s)
- A Switlicka
- Department of Crystallography, Institute of Chemistry, University of Silesia, 9th Szkolna St., 40-006 Katowice, Poland.
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27
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Kalinke LHG, Cardoso JCO, Rabelo R, Valdo AK, Martins FT, Cano J, Julve M, Lloret F, Cangussu D. From Paramagnetic to Single‐Molecule Magnet Behaviour in Heterobimetallic Compounds Containing the Tetrakis(thiocyanato‐
κN
)cobaltate(II) Anion. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201701177] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Lucas H. G. Kalinke
- IFG Instituto Federal Goiás Av. Pedro Ludovico, s/n, Reny Cury 75131‐457 Anápolis GO Brazil
- Instituto de Química Universidade Federal de Goiás Av. Esperança, s/n Campus Samabaia 74690‐900 Goiânia GO Brazil
| | - Jocielle C. O. Cardoso
- IFG Instituto Federal Goiás Av. Pedro Ludovico, s/n, Reny Cury 75131‐457 Anápolis GO Brazil
| | - Renato Rabelo
- Instituto de Química Universidade Federal de Goiás Av. Esperança, s/n Campus Samabaia 74690‐900 Goiânia GO Brazil
| | - Ana K. Valdo
- Instituto de Química Universidade Federal de Goiás Av. Esperança, s/n Campus Samabaia 74690‐900 Goiânia GO Brazil
| | - Felipe T. Martins
- Instituto de Química Universidade Federal de Goiás Av. Esperança, s/n Campus Samabaia 74690‐900 Goiânia GO Brazil
| | - Joan Cano
- Departament de Química Inorgànica, Instituto de Ciencia Molecular (ICMol) C/ Catedrático José Beltrán 2 46980 Paterna,Valencia Spain
| | - Miguel Julve
- Departament de Química Inorgànica, Instituto de Ciencia Molecular (ICMol) C/ Catedrático José Beltrán 2 46980 Paterna,Valencia Spain
| | - Francesc Lloret
- Departament de Química Inorgànica, Instituto de Ciencia Molecular (ICMol) C/ Catedrático José Beltrán 2 46980 Paterna,Valencia Spain
| | - Danielle Cangussu
- Instituto de Química Universidade Federal de Goiás Av. Esperança, s/n Campus Samabaia 74690‐900 Goiânia GO Brazil
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28
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Huang W, Li Y, Yong J, Liu Y, Wu D. Hydrazone-based cobalt complexes toward multielectron redox and spin crossover. RSC Adv 2018; 8:17159-17167. [PMID: 35539225 PMCID: PMC9081832 DOI: 10.1039/c8ra02963f] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 04/19/2018] [Indexed: 01/14/2023] Open
Abstract
Hydrazone-based derivatives modified by substitution at different positions were utilized to prepare a series of bis-homoleptic cobalt complexes. One species, [CoIII(L1)2]+ (1), which incorporated deprotonated ligands, adopted a Co(iii) diamagnetic ground state. However, the substituent of a hydrogen atom with a methyl group precluded the possibility of deprotonation upon metal coordination, which led to two species, [CoII(L2Me)2]2+ (2) and [CoII(L3NO2)2]2+, (3) which underwent a gradual spin crossover with an adjustable substituent effect and a mixed character of low-spin (doublet) and high-spin (quartet) populations in wide temperature ranges. Depending on the electronic effects of the substituents on the ligand, the multielectron redox behavior of the cobalt center was systematically modulated as well. This result demonstrates redox-switchable spin crossover in a new hydrazone-based Co(ii) system, in which the deprotonation of the coordination pocket and substituent groups in aromatic ligands can have a profound effect on the redox potential and spin state of the metal center. Hydrazone-based derivatives modified by substitution at different positions were utilized to prepare a series of bis-homoleptic cobalt complexes toward multielectron redox and spin crossover.![]()
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Affiliation(s)
- Wei Huang
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology
- Collaborative Innovation Center of Advanced Catalysis & Green Manufacturing
- School of Petrochemical Engineering
- Changzhou University
- Changzhou
| | - Yujie Li
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology
- Collaborative Innovation Center of Advanced Catalysis & Green Manufacturing
- School of Petrochemical Engineering
- Changzhou University
- Changzhou
| | - Juan Yong
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology
- Collaborative Innovation Center of Advanced Catalysis & Green Manufacturing
- School of Petrochemical Engineering
- Changzhou University
- Changzhou
| | - Yang Liu
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology
- Collaborative Innovation Center of Advanced Catalysis & Green Manufacturing
- School of Petrochemical Engineering
- Changzhou University
- Changzhou
| | - Dayu Wu
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology
- Collaborative Innovation Center of Advanced Catalysis & Green Manufacturing
- School of Petrochemical Engineering
- Changzhou University
- Changzhou
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29
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Wei HW, Yang QF, Lai XY, Wang XZ, Yang TL, Hou Q, Liu XY. Field-induced slow relaxation of magnetization in a distorted octahedral mononuclear high-spin Co(ii) complex. CrystEngComm 2018. [DOI: 10.1039/c7ce01981e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
By adopting the strategy of mixed rigid ligands, two novel mononuclear complexes with distorted octahedral geometries are obtained. SIM-type slow magnetic relaxation behavior is observed in Co(ii)-based complexes.
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Affiliation(s)
- Hai-Wen Wei
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering
- Ningxia University
- Yinchuan
- China
- College of Chemistry and Chemical Engineering
| | - Qing-Feng Yang
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering
- Ningxia University
- Yinchuan
- China
- College of Chemistry and Chemical Engineering
| | - Xiao-Yong Lai
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering
- Ningxia University
- Yinchuan
- China
- College of Chemistry and Chemical Engineering
| | - Xiao-Zhong Wang
- College of Chemistry and Chemical Engineering
- Ningxia University
- Yinchuan
- China
| | - Tian-Lin Yang
- College of Chemistry and Chemical Engineering
- Ningxia University
- Yinchuan
- China
| | - Qin Hou
- College of Chemistry and Material Science
- Shandong Agricultural University
- Taian
- China
| | - Xiang-Yu Liu
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering
- Ningxia University
- Yinchuan
- China
- College of Chemistry and Chemical Engineering
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30
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Shao D, Deng L, Shi L, Wu D, Wei X, Yang S, Wang X. Slow Magnetic Relaxation and Spin‐Crossover Behavior in a Bicomponent Ion‐Pair Cobalt(II) Complex. Eur J Inorg Chem 2017. [DOI: 10.1002/ejic.201700719] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Dong Shao
- School of Chemistry and Chemical Engineering State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced Microstructures Nanjing University 210023 Nanjing P. R. China
| | - Lin‐Dan Deng
- School of Chemistry and Chemical Engineering State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced Microstructures Nanjing University 210023 Nanjing P. R. China
| | - Le Shi
- School of Chemistry and Chemical Engineering State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced Microstructures Nanjing University 210023 Nanjing P. R. China
| | - Dong‐Qing Wu
- School of Chemistry and Chemical Engineering State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced Microstructures Nanjing University 210023 Nanjing P. R. China
| | - Xiao‐Qin Wei
- School of Chemistry and Chemical Engineering State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced Microstructures Nanjing University 210023 Nanjing P. R. China
| | - Si‐Run Yang
- School of Chemistry and Chemical Engineering State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced Microstructures Nanjing University 210023 Nanjing P. R. China
| | - Xin‐Yi Wang
- School of Chemistry and Chemical Engineering State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced Microstructures Nanjing University 210023 Nanjing P. R. China
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