1
|
Wu DQ, Kumari K, Wan Y, Gao X, Guo M, Liu G, Shao D, Zhai B, Singh SK. Binuclear cobalt(II) and two-dimensional manganese(II) coordination compounds self-assembled by mixed bipyridine-tetracarboxylic ligands with single-ion magnet properties. Dalton Trans 2023; 52:16197-16205. [PMID: 37873572 DOI: 10.1039/d3dt03016d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
A cobalt(II) complex and manganese(II) coordination polymer, formulated as [Co2(H2btca)(mbpy)4][H2btca]·4H2O (1) and {Mn2(btca)(mbpy)2(H2O)2}n (2) (H4btca = 1,2,4,5-benzenetetracarboxylic acid; mbpy = 4,4'-dimethyl-2,2'-bipyridyl), constructed by mixed bipyridine-tetracarboxylic ligands were synthesized and characterized. Single-crystal structural analyses reveal that compound 1 is a discrete neutral binuclear molecule, while compound 2 is a two-dimensional (2D) coordination polymer. The metal ions in these compounds are well isolated, with an intramolecular Co2+⋯Co2+ distance of 9.170 Å for 1 and Mn2+⋯Mn2+ separation of 10.984 and 11.164 Å for 2 due to the bulk tetracarboxylic linker. This isolation gives rise to a single-ion magnetism origin of the compounds. Magnetic studies reveal a large zero-field splitting parameter D of 82.6 cm-1 for 1, while a very small D of 0.42 cm-1 was observed for 2. Interestingly, dynamic ac magnetic measurements exhibited slow magnetic relaxation under the external dc field of the two compounds, revealing the field-supported single-ion magnet (SIM) of 1 and 2. The detailed theoretical calculations were further applied to understand the electronic structures, magnetic anisotropy, and relaxation dynamics in 1 and 2. Combined with our recently reported compound (Eur. J. Inorg. Chem., 2022, e202200354), the foregoing results provide not only a rare binuclear cobalt(II) SIM and the first 2D manganese(II) SIM coordination polymer but also a bipyridine-tetracarboxylic ligand approach toward novel SIMs.
Collapse
Affiliation(s)
- Dong-Qing Wu
- Engineering Research Center of Photoelectric Functional Material, School of Chemistry and Chemical Engineering, Shangqiu Normal University, Shangqiu 476000, P. R. China.
| | - Kusum Kumari
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi-502285, Sangareddy, Telangana, India.
| | - Yi Wan
- Hubei Key Laboratory of Processing and Application of Catalytic Materials, College of Chemistry and Chemical Engineering, Huanggang Normal University, Huanggang 438000, P. R. China.
| | - Xueling Gao
- Engineering Research Center of Photoelectric Functional Material, School of Chemistry and Chemical Engineering, Shangqiu Normal University, Shangqiu 476000, P. R. China.
| | - Mengxi Guo
- Engineering Research Center of Photoelectric Functional Material, School of Chemistry and Chemical Engineering, Shangqiu Normal University, Shangqiu 476000, P. R. China.
| | - Genyan Liu
- Hubei Key Laboratory of Novel Reactor and Green Chemical Technology, Wuhan Institute of Technology, Wuhan 430205, P. R. China
| | - Dong Shao
- Hubei Key Laboratory of Processing and Application of Catalytic Materials, College of Chemistry and Chemical Engineering, Huanggang Normal University, Huanggang 438000, P. R. China.
| | - Bin Zhai
- Engineering Research Center of Photoelectric Functional Material, School of Chemistry and Chemical Engineering, Shangqiu Normal University, Shangqiu 476000, P. R. China.
| | - Saurabh Kumar Singh
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi-502285, Sangareddy, Telangana, India.
| |
Collapse
|
2
|
Li Y, Zeng Z, Guo Y, Liu X, Zhang YQ, Ouyang Z, Wang Z, Liu X, Zheng YZ. Synergy of Magnetic Anisotropy and Ferromagnetic Interaction Triggering a Dimeric Cr(II) Zero-Field Single-Molecule Magnet. Inorg Chem 2023; 62:6297-6305. [PMID: 37040590 DOI: 10.1021/acs.inorgchem.2c04359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
A novel CrII-dimeric complex, [CrIIN(SiiPr3)2(μ-Cl)(THF)]2 (1), has been successfully constructed using a bulky silyl-amide ligand. Single-crystal structure analysis reveals that complex 1 exhibits a binuclear motif, with a Cr2Cl2 rhombus core, where two equivalent tetra-coordinate CrII centers in the centrosymmetric unit display quasi-square planar geometry. The crystal structure has been well simulated and explored by density functional theory calculations. The axial zero-field splitting parameter (D < 0) with a small rhombic (E) value is unambiguously determined by systematic investigations of magnetic measurements, high-frequency electron paramagnetic resonance spectroscopy, and ab initio calculations. Remarkably, ac magnetic susceptibility data unveil that 1 features slow dynamic magnetic relaxation typical of single-molecule magnet behavior with Ueff = 22 K in the absence of a dc field. This increases up to 35 K under a corresponding static field. Moreover, magnetic studies and theoretical calculations point out that a non-negligible ferromagnetic coupling (FMC) exists in the dimeric Cr-Cr units of 1. The coexistence of magnetic anisotropy and FMC contributes to the first case of CrII-based single-molecule magnets (SMMs) under zero dc field.
Collapse
Affiliation(s)
- Yuzhu Li
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China
| | - Zhaopeng Zeng
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China
| | - Yan Guo
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China
| | - Xingman Liu
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China
| | - Yi-Quan Zhang
- Jiangsu Key Laboratory for NSLSCS, School of Physical Science and Technology, Nanjing Normal University, Nanjing 210023, China
| | - Zhongwen Ouyang
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Zhenxing Wang
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Xiangyu Liu
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China
| | - Yan-Zhen Zheng
- Frontier Institute of Science and Technology, School of Chemistry and School of Physics, Xi'an Jiaotong University, Xi'an, Shaanxi 710054, China
| |
Collapse
|
3
|
Yao B, Zhang YQ, Deng YF, Li T, Zhang YZ. Series of Benzoquinone-Bridged Dicobalt(II) Single-Molecule Magnets. Inorg Chem 2022; 61:15392-15397. [PMID: 36134570 DOI: 10.1021/acs.inorgchem.2c01851] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Mononuclear complexes within a particular coordination geometry have been well recognized for high-performance single-molecule magnets (SMMs), while the incorporation of such well-defined geometric ions into multinuclear complexes remains less explored. Using the rigid 2-(di(1H-pyrazol-1-yl)methyl)-6-(1H-pyrazol-1-yl)pyridine (PyPz3) ligand, here, we prepared a series of benzoquinone-bridged dicobalt(II) SMMs [{(PyPz3)Co}2(L)][PF6]2, (1, L = 2,5-dioxo-1,4-benzoquinone (dhbq2-); 2, L = chloranilate (CA2-); and 3, L = bromanilate (BA2-)), in which each Co(II) center adopts a distorted trigonal prismatic (TPR) geometry and the distortion increases with the sizes of 3,6-substituent groups (H (1) < Cl (2) < Br (3)). Accordingly, the magnetic study revealed that the axial anisotropy parameter (D) of the Co ions decreased from -78.5 to -56.5 cm-1 in 1-3, while the rhombic one (E) increased significantly. As a result, 1 exhibited slow relaxation of magnetization under a zero dc field, while both 2 and 3 showed only the field-induced SMM behaviors, likely due to the increased rhombic anisotropy that leads to the serious quantum tunneling of the magnetization. Our study demonstrated that the relaxation dynamics and performances of a multinuclear complex are strongly dependent on the coordination geometry of the local metal ions, which may be engineered by modifying the substituent groups.
Collapse
Affiliation(s)
- Binling Yao
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Yi-Quan Zhang
- Jiangsu Key Laboratory for NSLSCS, School of Physical Science and Technology, Nanjing Normal University, Nanjing 210023, China
| | - Yi-Fei Deng
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Tianran Li
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Yuan-Zhu Zhang
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| |
Collapse
|
4
|
Shao D, Moorthy S, Zhou Y, Wu ST, Zhu JY, Yang J, Wu D, Tian Z, Singh SKK. Field-induced slow magnetic relaxation behaviours in binuclear cobalt(II) metallocycle and exchange-coupled cluster. Dalton Trans 2022; 51:9357-9368. [DOI: 10.1039/d2dt01620f] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Precise control of structures and magnetic properties of a molecular material constitutes an important challenge to realize the tailor-made magnetic function. Herein, we reported that the ligand-directed coordination self-assembly of...
Collapse
|
5
|
Yao B, Singh MK, Deng YF, Zhang YZ. A Dicobalt(II) Single-Molecule Magnet via a Well-Designed Dual-Capping Tetrazine Radical Ligand. Inorg Chem 2021; 60:18698-18705. [PMID: 34823356 DOI: 10.1021/acs.inorgchem.1c02094] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The recent years have witnessed the glory development for the construction of high-performance mononuclear single molecule magnets (SMMs) within a specific coordination geometry, which, however, is not well applied in cluster-based SMMs due to the synthetic challenges. Given that the monocobalt(II) complexes within a trigonal-prismatic (TPR) coordination geometry have been classified as excellent SMMs with huge axial anisotropy (D ≈ -100 cm-1), here we designed and synthesized a new dual-capping tetrazine ligand, 3,6-bis(6-(di(1H-pyrazol-1-yl)methyl)pyridin-2-yl)-1,2,4,5-tetrazine (bpptz), and prepared a novel dicobalt(II) complex, [Cp2CoIII][{(hfac)CoII}2(bpptz•-)][hfac]2·2Et2O (1, hfac = hexafluoroacetylacetonate). In the structure of 1, the bpptz•- radical ligand enwraps two Co(II) centers within quasi-TPR geometries, which are further bridged by the tetrazine radical in the trans mode. The magnetic study revealed that the interaction between the Co centers and the tetrazine radical is strongly antiferromagnetic with a coupling constant (J) of -65.8 cm-1 (in the -2J formalism). Remarkably, 1 exhibited the typical SMM behavior with an effective energy barrier of 69 cm-1 under a 1.5 kOe dc field, among the largest for polynuclear transition metal SMMs. In addition, DFT and ab initio calculations suggested that the presence of a strong Co(II)-radical magnetic interaction effectively quenches the QTM effect and enhances the barrier height for the magnetization reversal.
Collapse
Affiliation(s)
- Binling Yao
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Mukesh Kumar Singh
- EastCHEM School of Chemistry, The University of Edinburgh, David Brewster Road, Edinburgh, Scotland EH9 3FJ, U.K
| | - Yi-Fei Deng
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Yuan-Zhu Zhang
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| |
Collapse
|