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Halder D, Jana Y, Piwowarska D, Gnutek P, Rudowicz C. Tailoring single-ion magnet properties of coordination polymer C 11H 18DyN 3O 9 (Dy-CP) using the radial effective charge model (RECM) and superposition model (SPM). Phys Chem Chem Phys 2024; 26:19947-19959. [PMID: 38993160 DOI: 10.1039/d4cp01861c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/13/2024]
Abstract
We investigate Dy-based coordination polymer C11H18DyN3O9 (Dy-CP) exhibiting single-ion magnet (SIM) properties, e.g., quantum tunnelling of magnetization (QTM), magnetic anisotropy, magnetic relaxation, and effective energy barrier (Ueff). To elucidate the underlying mechanisms, crystal field parameters (CFPs) for Dy3+ ions were modelled using the radial effective charge model (RECM) and superposition model (SPM), and the computational packages SIMPRE and SPECTRE. The modelled CFPs enable the prediction of the energy levels and associated wave functions, which successfully explain the field-induced Dy-CP SIM properties. The so-calculated magnetic susceptibility and isothermal magnetization match the experimental data reasonably well. The smaller energy separations of the first (Δ0-1 ∼ 31 cm-1) and the second (Δ0-2 = 74 cm-1) excited Kramers doublets suggest small Ueff = 65 cm-1 for Dy-CP. The magnetic moments of Dy3+ ions exhibit an easy-axis type magnetic anisotropy in the ground state, but change orientation in the excited states due to mixing of states from different Kramers doublets. Low-symmetry CF components play a crucial role in connecting different |±MJ〉 states within the ground multiplet, resulting in QTM and magnetic relaxation to the ground state occurring via the excited states. The RECM and SPM calculated CFP sets are standardized employing the 3DD package to enable meaningful comparison and assessing their mutual equivalence. The results demonstrate the correlation between structural and electronic features of the molecule and site symmetry and distortion of the local coordination polyhedra with SIM properties, offering insights for rational design of new SIMs. The importance of considering low-symmetry aspects in CFP modelling for accurate predictions of magnetic properties is highlighted. This study provides deeper understanding of field-induced behaviour in rare-earth-based SIMs and approaches for rationalization of experimentally measured SIMs' properties.
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Affiliation(s)
- Dinabandhu Halder
- Department of Physics, University of Kalyani, Kalyani-741235, Nadia, WB, India.
| | - Yatramohan Jana
- Department of Physics, University of Kalyani, Kalyani-741235, Nadia, WB, India.
| | - Danuta Piwowarska
- Faculty of Mechanical Engineering and Mechatronics, West Pomeranian University of Technology in Szczecin, 70-311 Szczecin, Poland
| | - Paweł Gnutek
- Faculty of Mechanical Engineering and Mechatronics, West Pomeranian University of Technology in Szczecin, 70-311 Szczecin, Poland
| | - Czesław Rudowicz
- Faculty of Chemistry, Adam Mickiewicz University, 61-614 Poznań, Poland.
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Kumar Sahu P, Kharel R, Shome S, Goswami S, Konar S. Understanding the unceasing evolution of Co(II) based single-ion magnets. Coord Chem Rev 2023. [DOI: 10.1016/j.ccr.2022.214871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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3
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Dragancea D, Novitchi G, Madalan AM, Alexandru MG, Shova S, Andruh M. Trinuclear cyanido-bridged MII-WV complexes (M = Mn, Co): crystal structures and magnetic properties. Polyhedron 2022. [DOI: 10.1016/j.poly.2022.115839] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Sutter JP, Béreau V, Jubault V, Bretosh K, Pichon C, Duhayon C. Magnetic anisotropy of transition metal and lanthanide ions in pentagonal bipyramidal geometry. Chem Soc Rev 2022; 51:3280-3313. [PMID: 35353106 DOI: 10.1039/d2cs00028h] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The magnetic anisotropy associated with a pentagonal bipyramidal (PBP) coordination sphere is examined on the basis of experimental and theoretical investigations. The origin and the characteristics of this anisotropy are discussed in relation to the electronic configuration of the metal ions. The effects of crystal field, structural distortion, and a second-coordination sphere on the observed anisotropies for transition meal and lanthanide ions are outlined. For the Ln derivatives, we focus on compounds showing SMM-like behavior (i.e. slow relaxation of their magnetization) in order to highlight the essential chemical and structural parameters for achieving strong axial anisotropy. The use of PBP complexes to impart controlled magnetic anisotropy in polynuclear species such as SMMs or SCMs is also addressed. This review of the magnetic anisotropies associated with a pentagonal bipyramidal coordination sphere for transition metal and lanthanide ions is intended to highlight some general trends that can guide chemists towards designing a compound with specific properties.
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Affiliation(s)
- Jean-Pascal Sutter
- Laboratoire de Chimie de Coordination du CNRS (LCC-CNRS), Université de Toulouse, CNRS, Toulouse, France.
| | - Virginie Béreau
- Laboratoire de Chimie de Coordination du CNRS (LCC-CNRS), Université de Toulouse, CNRS, Toulouse, France. .,Université de Toulouse, Institut Universitaire de Technologie Paul Sabatier-Département de Chimie, Av. Georges Pompidou, F-81104 Castres, France
| | - Valentin Jubault
- Laboratoire de Chimie de Coordination du CNRS (LCC-CNRS), Université de Toulouse, CNRS, Toulouse, France.
| | - Kateryna Bretosh
- Laboratoire de Chimie de Coordination du CNRS (LCC-CNRS), Université de Toulouse, CNRS, Toulouse, France.
| | - Céline Pichon
- Laboratoire de Chimie de Coordination du CNRS (LCC-CNRS), Université de Toulouse, CNRS, Toulouse, France.
| | - Carine Duhayon
- Laboratoire de Chimie de Coordination du CNRS (LCC-CNRS), Université de Toulouse, CNRS, Toulouse, France.
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Srivastava AK, Mondal A, Konar S, Pal S. A tetra Co(II/III) complex with an open cubane Co 4O 4 core and square-pyramidal Co(II) and octahedral Co(III) centres: bifunctional electrocatalytic activity towards water splitting at neutral pH. Dalton Trans 2022; 51:4510-4521. [PMID: 35234225 DOI: 10.1039/d1dt04086c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The reaction of 2,6-diformyl-4-methylphenol, 4-methoxybenzoylhydrazine and Co(OAc)2·4H2O in 1 : 2 : 2 mole ratio in methanol under aerobic conditions produced in 61% yield a tetranuclear complex having the molecular formula [CoIICoIII(μ-OAc)(μ3-OH)(μ-L)]2 where OAc- and L3- represent acetate and N',N''-(5-methyl-2-oxido-1,3-phenylene)bis(methan-1-yl-1-ylidene)bis(4-methoxybenzoylhydrazonate), respectively. The elemental analysis and the mass spectrometric data confirmed the molecular formula of the complex. It is electrically non-conducting and paramagnetic. The complex crystallized as acetonitrile solvate. The X-ray structure shows that each Co(II) centre has a distorted square-pyramidal NO4 coordination sphere, while each Co(III) centre is in a distorted octahedral NO5 environment. The four metal atoms and the four bridging O-atoms form an open cubane type Co4O4 motif. In the crystal lattice, self-assembly of the solvated complex via intermolecular O-H⋯O interaction leads to a two-dimensional network structure. The infrared and electronic spectroscopic features of the complex are consistent with its molecular structure. Cryomagnetic measurements together with theoretical calculations suggest the presence of easy-axis anisotropy for the square-pyramidal Co(II) centres. The complex is redox-active and displays metal centred oxidation and reduction responses on the anodic and cathodic sides, respectively, of the Ag/AgCl electrode. Bifunctional heterogeneous electrocatalytic activity of the complex towards O2 and H2 evolution reactions (OER and HER) in neutral aqueous medium has been explored in detail.
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Affiliation(s)
| | - Arpan Mondal
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal 462066, India
| | - Sanjit Konar
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal 462066, India
| | - Samudranil Pal
- School of Chemistry, University of Hyderabad, Hyderabad 500 046, India.
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6
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Mondal A, Konar S. Effect of an axial coordination environment on quantum tunnelling of magnetization for dysprosium single-ion magnets with theoretical insight. Dalton Trans 2022; 51:1464-1473. [PMID: 34988577 DOI: 10.1039/d1dt03678e] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Herein, we report two mononuclear dysprosium complexes [Dy(H4L){B(OMe)2(Ph)2}2](Cl)·MeOH (1) and [Dy(H4L){MeOH)2(NCS)2}](Cl) (2) [where H4L = 2,2'-(pyridine-2,6-diylbis(ethan-1-yl-1-ylidene))bis(N-phenylhydrazinecarboxamide)] with different axial coordination environments. The structural analysis revealed that the pentadentate H4L ligand binds through the equatorial position in both complexes. In complex 1, the axial positions are occupied by bidentate dimethoxydiphenyleborate [B(OMe)2(Ph)2]-. On the other hand, in complex 2, one axial position is occupied by two NCS- and one MeOH molecule while another MeOH molecule is coordinated to the other axial position. Magnetic measurements disclose the presence of field-induced slow relaxation of magnetization with an energy barrier of Ueff = 30 K for 1 whereas no such effective barrier was observed in complex 2. Detailed analysis of field and temperature dependence of the relaxation time confirms the major role of Raman, QTM, and direct processes rather than the Orbach process in complex 1. It was observed that [B(OMe)2(Ph)2]- provides higher axial anisotropy which slows down the QTM process (relaxation time for the QTM process is 2.70 × 10-5 s) in 1 as compared to NCS anions and MeOH molecules in 2 (1.03 × 10-8 s), and is responsible for the absence of an effective energy barrier in the latter complex as confirmed by ab initio calculations. The calculations also show that the presence of a large bidentate dimethoxydiphenyleborate ligand in axial positions may result in high-performance Dy-based single-ion magnets.
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Affiliation(s)
- Arpan Mondal
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass road, Bhauri, Bhopal-462066, MP, India.
| | - Sanjit Konar
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass road, Bhauri, Bhopal-462066, MP, India.
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Qin Y, Wu Y, Luo S, Xi J, Guo Y, Ding Y, Zhang J, Liu X. Modulation of the magnetic dynamics of pentagonal-bipyramidal Co( ii) complexes by fine-tuning the coordination microenvironment. Dalton Trans 2022; 51:17089-17096. [DOI: 10.1039/d2dt02345h] [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
Dynamic magnetic behaviours of a series of Co(ii) SIMs with pentagonal-bipyramidal geometry have been modulated by an alteration of the ligand field effect.
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Affiliation(s)
- Yuanyuan Qin
- State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China
| | - Yuewei Wu
- State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China
| | - Shuchang Luo
- College of Chemical Engineering, Guizhou University of Engineering Science, Bijie 551700, China
| | - Jing Xi
- 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
| | - Yi Ding
- State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China
| | - Jun Zhang
- State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, 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
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Peng M, Wu XF, Wang LX, Chen SH, Xiang J, Jin XX, Yiu SM, Wang BW, Gao S, Lau TC. Slow magnetic relaxation in high-coordinate Co(II) and Fe(II) compounds bearing neutral tetradentate ligands. Dalton Trans 2021; 50:15327-15335. [PMID: 34636819 DOI: 10.1039/d1dt02575a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The first-row transition metal compounds, [MII(L1)2](ClO4)2 (M = Ni (1); Co (2)), have been prepared by treatment of a neutral tetradentate ligand (L1 = N2,N9-dibutyl-1,10-phenanthroline-2,9-dicarboxamide) with metal perchlorate salts in MeOH. Both compounds have been structurally characterized by X-ray crystallography and it was found that the coordination numbers are 6 and 7, respectively. The reaction of 6,6'-bis(2-tbutyl-tetrazol-5-yl)-2,2'-bipyridine (L2) with hydrated FeII(ClO4)2 afforded a 8-coordinate Fe(II) compound, [FeII(L2)2](ClO4)2 (3); however its reaction with hydrated CoII(ClO4)2 resulted in 6-coordinate [CoII(L2)2](ClO4)2. It is interesting to observe field-induced slow magnetic relaxation in the 7-coordinate Co(II) compound 2 and 8-coordinate Fe(II) compound 3, which further supports the validity of designing high coordination number compounds as single-molecule magnets. Direct current magnetic studies demonstrate that 2 has a very large positive D value (56.2 cm-1) and a small E value (0.66 cm-1), indicating easy plane magnetic anisotropy. Consistent with the larger D value, an effective spin-reversal barrier of Ueff = 100 K (71.4 cm-1) is obtained, which is the highest value reported for 7-coordinate Co(II) complexes with a pentagonal bipyramidal geometry. In contrast, 8-coordinate Fe(II) compound 3 exhibits uniaxial magnetic anisotropy.
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Affiliation(s)
- Min Peng
- College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou 434020, HuBei, P. R. China.
| | - Xiao-Fan Wu
- State Key Laboratory of Rare Earth Materials Chemistry and Applications and PKU-HKU Joint Laboratory on Rare Earth Materials and Bioinorganic Chemistry, Peking University, Beijing 100871, P. R. China.
| | - Li-Xin Wang
- College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou 434020, HuBei, P. R. China.
| | - Si-Huai Chen
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430073, P. R. China
| | - Jing Xiang
- College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou 434020, HuBei, P. R. China.
| | - Xin-Xin Jin
- State Key Laboratory of Rare Earth Materials Chemistry and Applications and PKU-HKU Joint Laboratory on Rare Earth Materials and Bioinorganic Chemistry, Peking University, Beijing 100871, P. R. China.
| | - Shek-Man Yiu
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong, P. R. China.
| | - Bing-Wu Wang
- State Key Laboratory of Rare Earth Materials Chemistry and Applications and PKU-HKU Joint Laboratory on Rare Earth Materials and Bioinorganic Chemistry, Peking University, Beijing 100871, P. R. China.
| | - Song Gao
- State Key Laboratory of Rare Earth Materials Chemistry and Applications and PKU-HKU Joint Laboratory on Rare Earth Materials and Bioinorganic Chemistry, Peking University, Beijing 100871, P. R. China. .,South China University of Technology, P. R. China
| | - Tai-Chu Lau
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong, P. R. China.
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Mondal A, Konar S. A remarkable energy barrier for spin reversal in a field induced dinuclear ytterbium single molecule magnet. Dalton Trans 2021; 50:13666-13670. [PMID: 34586116 DOI: 10.1039/d1dt02130c] [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
A dinuclear ytterbium complex has been designed with a strong ligand field in equatorial positions. Magnetic studies reveal the presence of easy-axis anisotropy and field induced slow relaxation of magnetization with a remarkable energy barrier, Ueff = 53.58 cm-1, the highest value reported for any Yb-based SMMs to date. Furthermore, the ab initio calculations disclose the importance of a weak axial ligand field to design high-performance Yb-based SMMs.
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Affiliation(s)
- Arpan Mondal
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal (IISERB), Bhopal By-pass Road, Bhauri, Bhopal-462066, India.
| | - Sanjit Konar
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal (IISERB), Bhopal By-pass Road, Bhauri, Bhopal-462066, India.
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10
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Kharwar AK, Mondal A, Sarkar A, Rajaraman G, Konar S. Modulation of Magnetic Anisotropy and Exchange Interaction in Phenoxide-Bridged Dinuclear Co(II) Complexes. Inorg Chem 2021; 60:11948-11956. [PMID: 34314144 DOI: 10.1021/acs.inorgchem.1c00956] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report a new class of four dimeric Co(II) complexes [Co2(bbpen)(X)2] (H2bbpen = N,N'-bis(2-hydroxybenzyl)-N,N'-bis(2-methylpyridyl)ethylenediamine) [X- = SCN (1), Cl (2), Br (3), and I (4)] with different coordination geometry of two Co(II) centers (trigonal-prismatic and pseudo-tetrahedral) and their magnetic study. Interestingly, the two Co(II) centers show two different types of magnetic anisotropy. State of the art ab initio CASSCF analysis reveals that the six-coordinate or the trigonal-prismatic Co(II) center possesses a consistently large negative axial zero-field splitting (negative D) parameter (∼-60 cm-1), while the four-coordinate or the pseudo-tetrahedral Co(II) center exhibits a range of D values from +13 to -23 cm-1. Ab initio calculations employing the lines model were used to estimate the magnetic exchange as both the Co(II) centers possess significant magnetic anisotropy. All the complexes display rare ferromagnetic interaction, and the strength of this interaction decreases as the ligand field on the pseudo-tetrahedral Co(II) center decreases from SCN- > Cl- > Br- > I-.
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Affiliation(s)
- Ajit Kumar Kharwar
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Bhopal, Bypass Road, Bhauri, Bhopal 462066, India
| | - Arpan Mondal
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Bhopal, Bypass Road, Bhauri, Bhopal 462066, India
| | - Arup Sarkar
- Department of Chemistry, Indian Institute of Technology, Bombay, Powai, Mumbai 400076, India
| | - Gopalan Rajaraman
- Department of Chemistry, Indian Institute of Technology, Bombay, Powai, Mumbai 400076, India
| | - Sanjit Konar
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Bhopal, Bypass Road, Bhauri, Bhopal 462066, India
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11
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Sahu PK, Mondal A, Konar S. A trapped hexaaqua Co II complex between the polyanionic sheets of decavanadate reveals high axial anisotropy and field induced SIM behaviour. Dalton Trans 2021; 50:3825-3831. [PMID: 33599634 DOI: 10.1039/d0dt04339g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work, we report an inorganic compound [{Co(H2O)6}2+{Na4V10O28}2-] (1) in which the polyanionic sheets of decavanadate play the role of a diamagnetic matrix that reduces the dipolar-dipolar and spin-spin interactions between [Co(H2O)6]+2 units to suppress the fast tunnelling of magnetization. Structural analysis reveals that each [Co(H2O)6]+2 complex is surrounded by four decavanadates and separated by a large internuclear distance (9 Å). It was also found that the adjacent decavanadates are connected via sodium ions and form a 2D sheet of the inorganic layer in which the [Co(H2O)6]2+ ions are present in between two layers. Detailed dc (direct current) and ac (alternating current) magnetic measurements disclose the presence of large easy-axis anisotropy (D = -102 cm-1) and field induced slow magnetic relaxation behaviour with a spin reversal barrier of Ueff = 50 K. Additionally, the temperature dependence of the relaxation time reveals that the Raman and QTM processes mainly play an important role rather than the thermally activated Orbach process in the overall relaxation dynamics of the studied compound. To analyse the electronic structure and magnetic properties of compound 1, ab initio calculations were performed which further support the experimental observations. Notably, the Ueff value of 1 represents the highest energy barrier reported for POM based SMMs with transition metal ions to date.
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Affiliation(s)
- Pradip Kumar Sahu
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal 462066, MP, India.
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12
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Mondal A, Konar S. Strong Equatorial Crystal Field Enhances the Axial Anisotropy and Energy Barrier for Spin Reversal Process in Yb 2 Single Molecule Magnets. Chemistry 2021; 27:3449-3456. [PMID: 33084133 DOI: 10.1002/chem.202004379] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/20/2020] [Indexed: 02/03/2023]
Abstract
The importance of equatorial crystal fields on magnetic anisotropy of ytterbium single molecule magnets (SMMs) is observed for the first time. Herein, we report three similar dinuclear ytterbium complexes with the formula [Yb2 (3-OMe-L)2 (DMF)2 (NO3 )2 ]⋅DMF (1), [Yb2 (3-H-L)2 (DMF)2 (NO3 )2 ]⋅DMF⋅H2 O (2), and [Yb2 (3-NO3 -L)2 (DMF)2 (NO3 )2 ] (3), [where 3-X-H2 L=N'-(2-hydroxy-3-X-benzylidene)picolinohydrazide, X=OMe (1), H (2) NO2 (3)]. Detailed magnetic measurements reveal the presence of weak antiferromagnetic interactions between the Yb centers and a field-induced slow relaxation of magnetization in all complexes. A higher energy barrier for spin reversal was observed for complex 1 (Ueff =50 K) and it decreases in the order of 2 (47 K) to 3 (40 K). Notably, complex 1 shows a remarkable energy barrier within the frequency range of 1-850 Hz reported for Yb-based SMMs. Further, ab initio calculations show a higher axial anisotropy and lower quantum tunneling of magnetization (QTM) in the ground state for 1 compared to 2 and 3. It was also observed that the presence of a strong crystal field in the equatorial plane (when the ∡ O1-Yb-O3 bond angle is close to 90°) enhances the axial anisotropy and improves the SMM behavior in the studied complexes. Both the experimental and theoretical analysis of relaxation dynamics discloses that Raman and QTM play major role on slow relaxation process for all complexes. To provide more insight into the exchange interactions, broken-symmetry DFT calculations were performed.
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Affiliation(s)
- Arpan Mondal
- Department of Chemistry, Indian Institute of Science Education and Research, Bhopal, Bhopal By-pass Road, Bhauri, Bhopal, 462066, Madhya Pradesh, India
| | - Sanjit Konar
- Department of Chemistry, Indian Institute of Science Education and Research, Bhopal, Bhopal By-pass Road, Bhauri, Bhopal, 462066, Madhya Pradesh, India
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13
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Kharwar AK, Mondal A, Konar S. Alignment of axial anisotropy of a mononuclear hexa-coordinated Co(ii) complex in a lattice shows improved single molecule magnetic behavior over a 2D coordination polymer having a similar ligand field. Dalton Trans 2021; 50:2832-2840. [DOI: 10.1039/d0dt04065g] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The parallel orientation of the anisotropic axes minimizes the transverse component and slow down the relaxation process and results in a higher energy barrier in 0D complex as compared to 2D framework where anisotropic axes are randomly oriented.
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Affiliation(s)
- Ajit Kumar Kharwar
- Department of Chemistry
- Indian Institute of Science Education and Research Bhopal
- Bhouri
- India
| | - Arpan Mondal
- Department of Chemistry
- Indian Institute of Science Education and Research Bhopal
- Bhouri
- India
| | - Sanjit Konar
- Department of Chemistry
- Indian Institute of Science Education and Research Bhopal
- Bhouri
- India
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14
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Mondal A, Raizada M, Sahu PK, Konar S. A new family of Fe 4Ln 4 (Ln = Dy III, Gd III, Y III) wheel type complexes with ferromagnetic interaction, magnetocaloric effect and zero-field SMM behavior. Inorg Chem Front 2021. [DOI: 10.1039/d1qi00781e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Observation of ferromagnetic interactions and single molecule toroic (SMT) behavior in Fe4Ln4 wheel complexes.
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Affiliation(s)
- Arpan Mondal
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal-462066, MP, India
| | - Mukul Raizada
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal-462066, MP, India
| | - Pradip Kumar Sahu
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal-462066, MP, India
| | - Sanjit Konar
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal-462066, MP, India
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15
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Wu Y, Xi J, Xiao T, Ferrando-Soria J, Ouyang Z, Wang Z, Luo S, Liu X, Pardo E. Switching of easy-axis to easy-plane anisotropy in cobalt( ii) complexes. Inorg Chem Front 2021. [DOI: 10.1039/d1qi01208h] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In situ microcalorimetry monitored assembly and coligand induced switching of the magnetic anisotropy sign have been observed in a β-diketonate-Co(ii) system.
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Affiliation(s)
- Yuewei Wu
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China
| | - Jing Xi
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China
| | - Tongtong Xiao
- Wuhan National High Magnetic Field Center & School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Jesús Ferrando-Soria
- Departamento de Química Inorgánica, Instituto de Ciencia Molecular (ICMOL), Universidad de Valencia, Paterna 46980, Valencia, Spain
| | - Zhongwen Ouyang
- Wuhan National High Magnetic Field Center & School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Zhenxing Wang
- Wuhan National High Magnetic Field Center & School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Shuchang Luo
- College of Chemical Engineering, Guizhou University of Engineering Science, Bijie 551700, 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
- China State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing, 210023, China
| | - Emilio Pardo
- Departamento de Química Inorgánica, Instituto de Ciencia Molecular (ICMOL), Universidad de Valencia, Paterna 46980, Valencia, Spain
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16
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Yang M, Ouyang ZJ, Zhong YJ, Cai JW, Li XH, Dong W. Field-induced slow magnetic relaxation from linear trinuclear Co III-Co II-Co III to grid [2 × 2] tetranuclear mixed-valence cobalt complexes. Dalton Trans 2020; 49:17017-17025. [PMID: 33191419 DOI: 10.1039/d0dt02863k] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
By employing the ligand azotetrazolyl-2,7-dihydroxynaphthalene (H3ATD), two linear trinuclear mixed-valence cobalt complexes [CoIICoIII2(HATD)4(H2O)4]·4DMA·3H2O (1, DMA = N,N-dimethylacetamide) and [CoIICoIII2(HATD)4(DMF)2(H2O)2]·2DMF·2H2O (2, DMF = N,N-dimethylformamide) were synthesized. Two [2 × 2] grid-like tetranuclear ion-pair complexes [CoII2CoIII2(HATD)4(bpp)2(H2O)2][CoIII(HATD)2]2·8DMF·6H2O (3, bpp = 2,6-di(pyrazol-1-yl)pyridine) and [CoII2CoIII2(HATD)4(bpp)2(H2O)2][CoIII(HATD)2]2·8DMSO·4MeOH (4, DMSO = dimethyl sulphoxide) were obtained by the reaction of complex 1/2 with tridentate-chelating bpp in DMF and DMSO, respectively. The single-crystal X-ray diffraction analysis indicated that complexes 1 and 2 have a similar core, in which the DMA in 1 acts as a guest molecule, and the DMF in 2 acts as a coordinated molecule and guest molecule. Complexes 3 and 4 are isostructural. All the Co(ii) ions in 1-4 are present in a distorted octahedral geometry. The ac susceptibility measurements show that all complexes display frequency-dependent peaks in the out-of-phase (χm'') component of the alternating-current (ac) magnetic susceptibility data, which is the characteristic behavior of single molecule magnets (SMMs).
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Affiliation(s)
- Meng Yang
- 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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17
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Slow Magnetic Relaxation in a One-Dimensional Coordination Polymer Constructed from Hepta-Coordinate Cobalt(II) Nodes. MAGNETOCHEMISTRY 2020. [DOI: 10.3390/magnetochemistry6040045] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A one-dimensional coordination polymer was synthesized employing hepta-coordinate CoII as nodes and dicyanamide as linkers. Detailed direct current (DC) and alternating current (AC) magnetic susceptibility measurements reveal the presence of field-induced slow magnetic relaxation behavior of the magnetically isolated seven-coordinate CoII center with an easy-plane magnetic anisotropy. Detailed ab initio calculations were performed to understand the magnetic relaxation processes. To our knowledge, the reported complex represents the first example of slow magnetic relaxation in a one-dimensional coordination polymer constructed from hepta-coordinate CoII nodes and dicyanamide linkers.
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18
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Shi T, Xu Y, Li MX, Liu CM, Nfor EN, Wang ZX. A 10-coordinate cerium(III) complex with a ferrocene-based terpyridine ligand exhibiting field-induced slow magnetic relaxation. Polyhedron 2020. [DOI: 10.1016/j.poly.2020.114695] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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19
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Mondal A, Kharwar AK, Sahu PK, Konar S. Alignment of Axial Anisotropy in a 1D Coordination Polymer shows Improved Field Induced Single Molecule Magnet Behavior over a Mononuclear Seven Coordinated Fe II Complex. Chem Asian J 2020; 15:2681-2688. [PMID: 32603028 DOI: 10.1002/asia.202000666] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 06/26/2020] [Indexed: 11/11/2022]
Abstract
Herein, we report a CN-bridged alternating FeII -NiII 1D chain to ensure the alignment of axial anisotropy and improve the single molecule magnet (SMM) behavior in seven coordinated FeII compound. The chain was constructed from hepta coordinated Fe(II) complex as an anisotropic building unit and diamagnetic nickel tetra cyanate as a bridging ligand. The magnetic measurements show the easy-axis anisotropy of the seven coordinated Fe(II) complex and field induced SMM behavior with spin reversal energy barrier Ueff =61(2) K (42 cm-1 ) and pre-exponential relaxation time τ0 =1.9×10-8 s. The detailed analysis of the relaxation dynamics discloses that the Orbach process plays an important role in slow relaxation of magnetization for this compound. Notably, this example represents a remarkable energy barrier observed in hepta coordinated Fe(II) SMMs. The ab initio calculations estimate the magnitude of axial anisotropy and show the parallel orientation of the anisotropic axis throughout the 1D polymeric chain. In addition, it is also reported that the presence of weak π accepter ligands in the distorted axial position enhance the easy-axis anisotropy.
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Affiliation(s)
- Arpan Mondal
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass road, Bhauri, Bhopal, 462066, MP, India
| | - Ajit Kumar Kharwar
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass road, Bhauri, Bhopal, 462066, MP, India
| | - Pradip Kumar Sahu
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass road, Bhauri, Bhopal, 462066, MP, India
| | - Sanjit Konar
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass road, Bhauri, Bhopal, 462066, MP, India
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20
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Mondal A, Roy S, Konar S. Remarkable Energy Barrier for Magnetization Reversal in 3D and 2D Dysprosium-Chloranilate-Based Coordination Polymers. Chemistry 2020; 26:8774-8783. [PMID: 32315101 DOI: 10.1002/chem.202000438] [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: 01/27/2020] [Revised: 04/16/2020] [Indexed: 12/26/2022]
Abstract
Herein, two coordination polymers (CPs) [{Dy(Cl2 An)1.5 (CH3 OH)}⋅4.5 H2 O]n (1) and [Dy(Cl2 An)1.5 (DMF)2 ]n (2), in which Cl2 An is chloranilate (2,5-dihydroxy-1,4-benzoquinone dianion), exhibiting field-induced single-molecule magnet behavior with moderate barrier of magnetization reversal are reported. Detailed structural and topological analysis disclosed that 1 has a 3D network, whereas 2 has a 2D layered-type structure. In both CPs, magnetic measurements showed weak antiferromagnetic exchange interaction between the dysprosium centers and field-induced slow magnetic relaxation with barriers of 175(9)K and 145(7)K for 1 and 2, respectively. Notably, the energy barriers of magnetization reversal of 1 and 2 are remarkable for metal-chloranilate-based 3D (1) and 2D (2) CPs. The temperature and field dependence of relaxation time indicate the presence of multiple relaxation pathways, such as direct, quantum tunneling of magnetization, Raman, and Orbach processes, in both CPs. Ab initio theoretical calculations reinforced the experimentally observed higher energy barrier in 1 as compared with 2 due to the presence of large transverse anisotropy in the ground state in the latter. The average transition magnetic moment between the computed low-lying spin-orbit states also rationalized the relaxation as Orbach and Raman processes through the first excited state. BS-DFT calculations were carried out for both CPs to provide more insight into the exchange interaction.
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Affiliation(s)
- Arpan Mondal
- Department of Chemistry, Indian Institute of Science Education and Research, Bhopal, Bhopal By-pass Road, Bhauri, Bhopal, 462066, Madhya Pradesh, India
| | - Subhadip Roy
- Department of Chemistry, The ICFAI University Tripura, Kamalghat, Mohanpur, Agartala, Tripura, 799210, India
| | - Sanjit Konar
- Department of Chemistry, Indian Institute of Science Education and Research, Bhopal, Bhopal By-pass Road, Bhauri, Bhopal, 462066, Madhya Pradesh, India
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21
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Mondal A, Wu S, Sato O, Konar S. Effect of Axial Ligands on Easy‐Axis Anisotropy and Field‐Induced Slow Magnetic Relaxation in Heptacoordinated Fe
II
Complexes. Chemistry 2020; 26:4780-4789. [DOI: 10.1002/chem.201905166] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Indexed: 11/11/2022]
Affiliation(s)
- Arpan Mondal
- Department of ChemistryIndian Institute of, Science Education and Research, Bhopal Bhopal By-pass Road, Bhauri Bhopal 462066 Madhya Pradesh India
| | - Shu‐Qi Wu
- Institute for Materials Chemistry and Engineering & IRCCSKyushu University 744 Motooka Nishi-ku 819-0395 Fukuoka Japan
| | - Osamu Sato
- Institute for Materials Chemistry and Engineering & IRCCSKyushu University 744 Motooka Nishi-ku 819-0395 Fukuoka Japan
| | - Sanjit Konar
- Department of ChemistryIndian Institute of, Science Education and Research, Bhopal Bhopal By-pass Road, Bhauri Bhopal 462066 Madhya Pradesh India
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22
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Zoufalý P, Čižmár E, Kuchár J, Herchel R. The Structural and Magnetic Properties of Fe II and Co II Complexes with 2-(furan-2-yl)-5-pyridin-2-yl-1,3,4-oxadiazole. Molecules 2020; 25:molecules25020277. [PMID: 31936620 PMCID: PMC7024161 DOI: 10.3390/molecules25020277] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 01/06/2020] [Accepted: 01/07/2020] [Indexed: 11/16/2022] Open
Abstract
Two novel coordination compounds containing heterocyclic bidentate N,N-donor ligand 2-(furan-2-yl)-5-(pyridin-2-yl)-1,3,4-oxadiazole (fpo) were synthesized. A general formula for compounds originating from perchlorates of iron, cobalt, and fpo can be written as: [M(fpo)2(H2O)2](ClO4)2 (M = Fe(II) for (1) Co(II) for (2)). The characterization of compounds was performed by general physico-chemical methods-elemental analysis (EA), Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR) in case of organics, and single crystal X-ray diffraction (sXRD). Moreover, magneto-chemical properties were studied employing measurements in static field (DC) for 1 and X-band EPR (Electron paramagnetic resonance), direct current (DC), and alternating current (AC) magnetic measurements in case of 2. The analysis of DC magnetic properties revealed a high spin arrangement in 1, significant rhombicity for both complexes, and large magnetic anisotropy in 2 (D = -21.2 cm-1). Moreover, 2 showed field-induced slow relaxation of the magnetization (Ueff = 65.3 K). EPR spectroscopy and ab initio calculations (CASSCF/NEVPT2) confirmed the presence of easy axis anisotropy and the importance of the second coordination sphere.
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Affiliation(s)
- Pavel Zoufalý
- Department of Inorganic Chemistry, Faculty of Science, Palacký University, 17. Listopadu 12, CZ-771 46 Olomouc, Czech Republic; (P.Z.); or
| | - Erik Čižmár
- Institute of Physics, Faculty of Science, P.J. Šafárik University in Košice, Park Angelinum 9, SK-041 54 Košice, Slovakia;
| | - Juraj Kuchár
- Department of Inorganic Chemistry, Faculty of Science, Palacký University, 17. Listopadu 12, CZ-771 46 Olomouc, Czech Republic; (P.Z.); or
- Department of Inorganic Chemistry, Institute of Chemistry, Faculty of Science, P.J. Šafárik University in Košice, Moyzesova 11, SK-041 54 Košice, Slovakia
| | - Radovan Herchel
- Department of Inorganic Chemistry, Faculty of Science, Palacký University, 17. Listopadu 12, CZ-771 46 Olomouc, Czech Republic; (P.Z.); or
- Correspondence: ; Tel.: +420-58563-4435
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23
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Kharwar AK, Konar S. Exchange coupled Co(ii) based layered and porous metal-organic frameworks: structural diversity, gas adsorption, and magnetic properties. Dalton Trans 2020; 49:4012-4021. [PMID: 32154532 DOI: 10.1039/d0dt00211a] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Four new Co(ii) based metal-organic frameworks (MOFs) ({[Co3(L)(TDCA)3(DMF)2]n·2nCH3CN}) (1), ({[Co3(L)2(BDCA)3]n·2nCH3CN}) (2), {[Co2(L)2(CA)2]n·4nCH3CN} (3) and {[Co2(L)(OBBA)2]n·3nCH3CN} (4) are synthesized, where L is [4'-(4-methoxyphenyl)-4,2':6',4''-terpyridine], a V-shaped flexible neutral spacer, and the four dicarboxylates are TDCA = thiophene 2,5-dicarboxylic acid, BDCA = benzene 1,4-dicarboxylic acid, CA = (1R,3S)-(+)-camphoric acid and OBBA = 4,4'-oxybisbenzoic acid. Structural analysis reveals that 1 and 2 are two dimensional (2D) layered structures having interesting sql and hxl topologies respectively with trinuclear SBUs (secondary building units). Compound 3 has a 3D structure, whereas 4 has a 2-fold interpenetrated 3D packing structure with a paddlewheel dinuclear SBU and both have pcu topology. Magnetic investigation revealed that 1, 3 and 4 show dominant antiferromagnetic behavior, while 2 shows ferromagnetic interaction at very low temperature. Interestingly 4 shows a sharp decrease in the χMT value from room temperature and this may be because of the direct Co(ii)Co(ii) interaction. Gas sorption studies reveal that 1, 2 and 3 show surface areas of 11.8 m2 g-1, 8.3 m2 g-1 and 28.5 m2 g-1 respectively and better adsorption behavior for CO2 over CH4, whereas 4 is nonporous in nature due to its 2-fold interpenetrated structure.
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Affiliation(s)
- Ajit Kumar Kharwar
- Department of Chemistry, Indian Institute of Science Education and Research, (IISER), Bhopal By-pass Road, Bhauri, Bhopal-462066, India.
| | - Sanjit Konar
- Department of Chemistry, Indian Institute of Science Education and Research, (IISER), Bhopal By-pass Road, Bhauri, Bhopal-462066, India.
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24
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Li HY, Zhao SN, Zang SQ, Li J. Functional metal–organic frameworks as effective sensors of gases and volatile compounds. Chem Soc Rev 2020; 49:6364-6401. [DOI: 10.1039/c9cs00778d] [Citation(s) in RCA: 434] [Impact Index Per Article: 108.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This review summarizes the recent advances of metal organic framework (MOF) based sensing of gases and volatile compounds.
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Affiliation(s)
- Hai-Yang Li
- Green Catalysis Center, and College of Chemistry
- Zhengzhou University
- Zhengzhou 450001
- China
| | - Shu-Na Zhao
- Green Catalysis Center, and College of Chemistry
- Zhengzhou University
- Zhengzhou 450001
- China
| | - Shuang-Quan Zang
- Green Catalysis Center, and College of Chemistry
- Zhengzhou University
- Zhengzhou 450001
- China
| | - Jing Li
- Department of Chemistry and Chemical Biology
- Rutgers University
- Piscataway
- USA
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25
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Yi G, Zhang C, Zhao W, Cui H, Chen L, Wang Z, Chen XT, Yuan A, Liu YZ, Ouyang ZW. Structure, magnetic anisotropy and relaxation behavior of seven-coordinate Co(ii) single-ion magnets perturbed by counter-anions. Dalton Trans 2020; 49:7620-7627. [DOI: 10.1039/d0dt01232g] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A series of mononuclear seven-coordinate complexes with the same coordination unit [Co(BPA-TPA)]2+ (BPA-TPA = pentapyidyldiamine) display the different slow magnetic relaxation processes perturbed by the variation of the counter anions.
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Affiliation(s)
- Gangji Yi
- School of Environmental and Chemical Engineering
- Jiangsu University of Science and Technology
- Zhenjiang 212003
- P. R. China
| | - Chunyang Zhang
- School of Environmental and Chemical Engineering
- Jiangsu University of Science and Technology
- Zhenjiang 212003
- P. R. China
| | - Wen Zhao
- School of Environmental and Chemical Engineering
- Jiangsu University of Science and Technology
- Zhenjiang 212003
- P. R. China
| | - Huihui Cui
- State Key Laboratory of Coordination Chemistry
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210093
- P. R. China
| | - Lei Chen
- School of Environmental and Chemical Engineering
- Jiangsu University of Science and Technology
- Zhenjiang 212003
- P. R. China
| | - Zhenxing Wang
- Wuhan National High Magnetic Field Center& School of Physics
- Huazhong University of Science and Technology
- Wuhan 430074
- P. R. China
| | - Xue-Tai Chen
- State Key Laboratory of Coordination Chemistry
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210093
- P. R. China
| | - Aihua Yuan
- School of Environmental and Chemical Engineering
- Jiangsu University of Science and Technology
- Zhenjiang 212003
- P. R. China
| | - Yuan-Zhong Liu
- Suzhou Institute of Biomedical Engineering and Technology
- Chinese Academy of Sciences
- Suzhou 215163
- P. R. China
- Jinan Guoke Medical Technology Development Co
| | - Zhong-Wen Ouyang
- Wuhan National High Magnetic Field Center& School of Physics
- Huazhong University of Science and Technology
- Wuhan 430074
- P. R. China
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26
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Maity S, Mondal A, Konar S, Ghosh A. The role of 3d–4f exchange interaction in SMM behaviour and magnetic refrigeration of carbonato bridged CuII2LnIII2 (Ln = Dy, Tb and Gd) complexes of an unsymmetrical N2O4 donor ligand. Dalton Trans 2019; 48:15170-15183. [DOI: 10.1039/c9dt02627d] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The role of exchange interaction between Cu(ii) and Ln(iii) ions in SMM behaviour and magnetocaloric effects has been extensively investigated by both experimental and theoretical CASSCF/RASSI-SO/SINGLE_ANISO methods.
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Affiliation(s)
- Souvik Maity
- Department of Chemistry
- University College of Science
- University of Calcutta
- Kolkata 700009
- India
| | - Arpan Mondal
- Department of Chemistry
- Indian Institute of Science Education and Research Bhopal
- Bhopal 462066
- India
| | - Sanjit Konar
- Department of Chemistry
- Indian Institute of Science Education and Research Bhopal
- Bhopal 462066
- India
| | - Ashutosh Ghosh
- Department of Chemistry
- University College of Science
- University of Calcutta
- Kolkata 700009
- India
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