1
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Sushila, Shivam K, Venugopalan P, Rani J, Tian H, Goswami S, Patra R. Design of Dinuclear Lanthanide Complexes from N
2
O
2
Donor Ligand for Single Molecule Magnets: Crystalline Architecture and Slow Magnetic Relaxation Studies. ChemistrySelect 2022. [DOI: 10.1002/slct.202103720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Sushila
- Department of Chemistry and Centre for Advance Studies Panjab University Chandigarh India
| | - Kumar Shivam
- Amity Institute of Click Chemistry Research & Studies (AICCRS) Amity University Noida India
| | - Paloth Venugopalan
- Department of Chemistry and Centre for Advance Studies Panjab University Chandigarh India
| | - Jyoti Rani
- School of Advance Chemical Sciences Shoolini University Solan Himachal Pradesh India
| | - Haiquan Tian
- Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry and Chemical Engineering Liaocheng University Liaocheng 252059 P. R. China
| | - Soumyabrata Goswami
- Department of Chemistry Amity Institute of Applied Sciences Amity University Kolkata India
| | - Ranjan Patra
- Department of Chemistry and Centre for Advance Studies Panjab University Chandigarh India
- Amity Institute of Click Chemistry Research & Studies (AICCRS) Amity University Noida India
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2
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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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3
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Shukla P, Roy S, Dolui D, Cañón-Mancisidor W, Das S. Pentanuclear Spirocyclic Ni4
Ln Derivatives: Field Induced Slow Magnetic Relaxation in the Dysprosium and Erbium Analogues. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.201901350] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Pooja Shukla
- Department of Chemistry; Institute of Infrastructure Technology Research And Management; Near Khokhra Circle, Maninagar East 380026 Ahmedabad Gujarat India
| | - Soumalya Roy
- Department of Chemistry; Institute of Infrastructure Technology Research And Management; Near Khokhra Circle, Maninagar East 380026 Ahmedabad Gujarat India
| | - Dependu Dolui
- Discipline of Chemistry; Indian Institute of Technology; 382355 Gandhinagar Gujarat India
| | - Walter Cañón-Mancisidor
- Facultad de Químicas y Biología; Departamento de Química de Materiales; Universidad de Santiago de Chile (USACH); Santiago Chile
- Departamento de Química de Materiales; Center for the Development of Nanoscience and Nanotechnology (CEDENNA); Santiago Chile
| | - Sourav Das
- Department of Chemistry; Institute of Infrastructure Technology Research And Management; Near Khokhra Circle, Maninagar East 380026 Ahmedabad Gujarat India
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4
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Zhang W, Xu SM, Zhu ZX, Ru J, Zhang YQ, Yao MX. Strong intramolecular DyIII–DyIII magnetic couplings up to 15.00 cm−1 in phenoxyl-bridged dinuclear 4f complexes. NEW J CHEM 2020. [DOI: 10.1039/c9nj05971g] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Unexpectedly, intramoleular DyIII–DyIII magnetic couplings are up to 15.00 cm−1 in the phenolate-bridged Dy2 complexes. And single-molecule magnet behavior is exhibited with effective energy of 76.18 K under zero dc field.
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Affiliation(s)
- Wei Zhang
- College of Chemistry & Molecular Engineering
- Nanjing Tech University
- Nanjing
- P. R. China
| | - Shao-Min Xu
- College of Chemistry & Molecular Engineering
- Nanjing Tech University
- Nanjing
- P. R. China
| | - Zhao-Xia Zhu
- College of Chemistry & Molecular Engineering
- Nanjing Tech University
- Nanjing
- P. R. China
| | - Jing Ru
- School of Chemistry and Chemical Engineering
- Liaocheng University
- Liaocheng
- P. R. China
| | - Yi-Quan Zhang
- Jiangsu Key Lab for NSLSCS
- School of Physical Science and Technology
- Nanjing Normal University
- Nanjing 210023
- China
| | - Min-Xia Yao
- College of Chemistry & Molecular Engineering
- Nanjing Tech University
- Nanjing
- P. R. China
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5
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Bazhenova TA, Mironov VS, Yakushev IA, Svetogorov RD, Maximova OV, Manakin YV, Kornev AB, Vasiliev AN, Yagubskii EB. End-to-End Azido-Bridged Lanthanide Chain Complexes (Dy, Er, Gd, and Y) with a Pentadentate Schiff-Base [N 3O 2] Ligand: Synthesis, Structure, and Magnetism. Inorg Chem 2019; 59:563-578. [PMID: 31858796 DOI: 10.1021/acs.inorgchem.9b02825] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The syntheses, structure and magnetic properties are reported for five novel 1D polymeric azido-bridged lanthanide complexes with the general formula {[Ln(DAPMBH)(N3)C2H5OH]C2H5OH}n where H2DAPMBH = 2,6-diacetylpyridine bis(4-methoxybenzoylhydrazone)-a new pentadentate pyridine-base [N3O2] ligand and Ln = Dy (1), Y0.930Dy0.070 (2), Er (3), Y0.923Er0.077 (4), and Gd (5). X-ray diffraction analysis of 1-5 show that the central lanthanide atoms are eight-coordinated with the N5O3 donor set originating from the ligand DAPMBH, one coordinated ethanol molecule and two end-to-end type N3- bridges connecting the metal centers into infinite chain. The [LnN5O3] coordination polyhedron can be regarded as a distorted dodecahedron (D2d). AC magnetic measurements revealed that compounds 1-4 show field-induced single-molecule magnet behavior, with estimated energy barriers Ueff ≈ 47-17 K. The experimental study of magnetic properties was complemented by theoretical analysis based on crystal-field calculations. Direct current magnetic susceptibility studies revealed marginally weak intrachain exchange interaction between Ln3+ ions mediated by the end-to-end azide bridging groups (J ≈ -0.015 cm-1 for 5). Comparative analysis of static and dynamic magnetic properties of magnetically concentrated (1, 3) and diluted (2, 4) Dy and Er compounds showed that, despite fascinating 1D azido-bridged chain structure, compounds 1 and 3 are not single-chain magnets; their magnetic behavior is largely due to single-ion magnetic anisotropy of individual Ln3+ ions.
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Affiliation(s)
- Tamara A Bazhenova
- Institute of Problems of Chemical Physics IPCP RAS , Chernogolovka 142432 , Russia
| | - Vladimir S Mironov
- Institute of Problems of Chemical Physics IPCP RAS , Chernogolovka 142432 , Russia.,Shubnikov Institute of Crystallography of Federal Scientific Research Centre "Crystallography and Photonics" RAS , Moscow 119333 , Russia
| | - Ilya A Yakushev
- Institute of Problems of Chemical Physics IPCP RAS , Chernogolovka 142432 , Russia.,Kurnakov Institute of General and Inorganic Chemistry IGIC RAS , Moscow 119991 , Russia.,National Research Center "Kurchatov Institute" , Moscow 123182 , Russia
| | | | - Olga V Maximova
- Institute of Problems of Chemical Physics IPCP RAS , Chernogolovka 142432 , Russia.,Lomonosov Moscow State University , Moscow 119991 , Russia.,National University of Science and Technology "MISiS" , Moscow 119049 , Russia
| | - Yuriy V Manakin
- Institute of Problems of Chemical Physics IPCP RAS , Chernogolovka 142432 , Russia
| | - Alexey B Kornev
- Institute of Problems of Chemical Physics IPCP RAS , Chernogolovka 142432 , Russia
| | - Alexander N Vasiliev
- Lomonosov Moscow State University , Moscow 119991 , Russia.,National University of Science and Technology "MISiS" , Moscow 119049 , Russia.,National Research South Ural State University , Chelyabinsk 454080 , Russia
| | - Eduard B Yagubskii
- Institute of Problems of Chemical Physics IPCP RAS , Chernogolovka 142432 , Russia
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6
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Zorina LV, Simonov SV, Sasnovskaya VD, Talantsev AD, Morgunov RB, Mironov VS, Yagubskii EB. Slow Magnetic Relaxation, Antiferromagnetic Ordering, and Metamagnetism in Mn II (H 2 dapsc)-Fe III (CN) 6 Chain Complex with Highly Anisotropic Fe-CN-Mn Spin Coupling. Chemistry 2019; 25:14583-14597. [PMID: 31361924 DOI: 10.1002/chem.201902551] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 07/29/2019] [Indexed: 11/07/2022]
Abstract
Reactions of [Mn(H2 dapsc)Cl2 ]⋅H2 O (dapsc=2,6- diacetylpyridine bis(semicarbazone)) with K3 [Fe(CN)6 ] and (PPh4 )3 [Fe(CN)6 ] lead to the formation of the chain polymeric complex {[Mn(H2 dapsc)][Fe(CN)6 ][K(H2 O)3.5 ]}n ⋅1.5n H2 O (1) and the discrete pentanuclear complex {[Mn(H2 dapsc)]3 [Fe(CN)6 ]2 (H2 O)2 }⋅4 CH3 OH⋅3.4 H2 O (2), respectively. In the crystal structure of 1 the high-spin [MnII (H2 dapsc)]2+ cations and low-spin hexacyanoferrate(III) anions are assembled into alternating heterometallic cyano-bridged chains. The K+ ions are located between the chains and are coordinated by oxygen atoms of the H2 dapsc ligand and water molecules. The magnetic structure of 1 is built from ferrimagnetic chains, which are antiferromagnetically coupled. The complex exhibits metamagnetism and frequency-dependent ac magnetic susceptibility, indicating single-chain magnetic behavior with a Mydosh-parameter φ=0.12 and an effective energy barrier (Ueff /kB ) of 36.0 K with τ0 =2.34×10-11 s for the spin relaxation. Detailed theoretical analysis showed highly anisotropic intra-chain spin coupling between [FeIII (CN)6 ]3- and [MnII (H2 dapsc)]2+ units resulting from orbital degeneracy and unquenched orbital momentum of [FeIII (CN)6 ]3- complexes. The origin of the metamagnetic transition is discussed in terms of strong magnetic anisotropy and weak AF interchain spin coupling.
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Affiliation(s)
- Leokadiya V Zorina
- Institute of Solid State Physics, Russian Academy of Sciences, Academician Ossipyan Str. 2, Chernogolovka MD, Russia
| | - Sergey V Simonov
- Institute of Solid State Physics, Russian Academy of Sciences, Academician Ossipyan Str. 2, Chernogolovka MD, Russia
| | - Valentina D Sasnovskaya
- Institute of Problems of Chemical Physics, Russian Academy of Sciences, Semenov's av. 1, Chernogolovka, MD, Russia
| | - Artem D Talantsev
- Institute of Problems of Chemical Physics, Russian Academy of Sciences, Semenov's av. 1, Chernogolovka, MD, Russia
| | - Roman B Morgunov
- Institute of Problems of Chemical Physics, Russian Academy of Sciences, Semenov's av. 1, Chernogolovka, MD, Russia
| | - Vladimir S Mironov
- Shubnikov Institute of Crystallography of Federal Scientific Research, Centre "Crystallography and Photonics", Russian Academy of Sciences, Leninskii av. 59, Moscow, Russia
| | - Eduard B Yagubskii
- Institute of Problems of Chemical Physics, Russian Academy of Sciences, Semenov's av. 1, Chernogolovka, MD, Russia
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7
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Field Induced Single Ion Magnetic Behaviour in Square-Pyramidal Cobalt(II) Complexes with Easy-Plane Magnetic Anisotropy. MAGNETOCHEMISTRY 2019. [DOI: 10.3390/magnetochemistry5010012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Two penta-coordinate CoII complexes with formulae [Co(14-TMC)Cl](BF4) (1, 14-TMC = 1,4,8,11-Tetramethyl-1,4,8,11-tetraazacyclotetradecane) and [Co(12-TBC)Cl](ClO4)·(MeCN) (2, 12-TBC = 1,4,7,10-Tetrabenzyl-1,4,7,10-tetraazacyclododecane) were synthesized and characterized. Structural analysis revealed that ligand coordinates to the CoII centre in a tetradentate fashion and the fifth position is occupied by chloride ion and the geometries around CoII centres are best described as distorted square pyramidal. Detailed magnetic measurements disclose the presence of significant easy-plane magnetic anisotropy and field induced slow magnetic relaxation behaviours of the studied complexes. More insight into the magnetic anisotropy has been given using ab initio theory calculations, which agree well with the experimental values and further confirmed the easy-plane magnetic anisotropy.
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8
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Field Induced Slow Magnetic Relaxation in a Non Kramers Tb(III) Based Single Chain Magnet. MAGNETOCHEMISTRY 2018. [DOI: 10.3390/magnetochemistry4040059] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Herein, we report a novel Tb(III) single chain magnet with the chemical formulae [Tb(μ-OH2)(phen)(μ-OH)(nb)2]n by using 4-nitrobenzoic acid (Hnb) and 1,10-phenanthroline (phen) as ligand system. The single-crystal X-ray diffraction reveals that 4-nitrobenzoic acid acts as a monodentate ligand, water and hydroxyl ions are the bridging ligand and the phen serves as a bidentate chelating ligand. The static magnetic susceptibility measurement (from 2 K to 300 K) shows ferromagnetic interaction at very low temperature (below 6 K). The alternating current (AC) susceptibility data of the complex show temperature and frequency dependence under an applied 2000 Oe DC (direct current) field. The phen moiety behaves as an antenna and enables the complex to show the green light fluorescence emission by absorption-energy transfer-emission mechanism. To calculate the exchange interaction, broken symmetry density functional theory (BS-DFT) calculations have been performed on a model compound which also reveals weak ferromagnetic interaction. Ab initio calculations reveals the anisotropic nature (gz = 15.8, gy, gy = 0) of the metal centre and the quasi doublet nature of ground state with small energy gap and that is well separated from the next excited energy state.
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9
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Mondal AK, Mondal A, Dey B, Konar S. Influence of the Coordination Environment on Easy-Plane Magnetic Anisotropy of Pentagonal Bipyramidal Cobalt(II) Complexes. Inorg Chem 2018; 57:9999-10008. [DOI: 10.1021/acs.inorgchem.8b01162] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Amit Kumar Mondal
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal, 462066 Madhya Pradesh, India
| | - Arpan Mondal
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal, 462066 Madhya Pradesh, India
| | - Bijoy Dey
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal, 462066 Madhya Pradesh, India
| | - Sanjit Konar
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal, 462066 Madhya Pradesh, India
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10
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Casanovas B, Font-Bardía M, Speed S, El Fallah MS, Vicente R. Field-Induced SMM and Visible/NIR-Luminescence Behaviour of Dinuclear LnIII
Complexes with 2-Fluorobenzoate. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201800229] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Berta Casanovas
- Departament de Química Inorgànica i Orgànica; Secció de Química Inorgànica; Universitat de Barcelona; Martí i Franquès 1-11 08028 Barcelona Spain
| | - Mercè Font-Bardía
- Departament de Mineralogia; Cristallografia i Dipòsits Minerals and Unitat de Difracció de R-X; Universitat de Barcelona; Solé i Sabarís 1-3 08028 Barcelona Spain
| | - Saskia Speed
- Departament de Química Inorgànica i Orgànica; Secció de Química Inorgànica; Universitat de Barcelona; Martí i Franquès 1-11 08028 Barcelona Spain
| | - Mohamed Salah El Fallah
- Departament de Química Inorgànica i Orgànica; Secció de Química Inorgànica; Universitat de Barcelona; Martí i Franquès 1-11 08028 Barcelona Spain
| | - Ramon Vicente
- Departament de Química Inorgànica i Orgànica; Secció de Química Inorgànica; Universitat de Barcelona; Martí i Franquès 1-11 08028 Barcelona Spain
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11
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Rasamsetty A, Das C, Sañudo EC, Shanmugam M, Baskar V. Effect of coordination geometry on the magnetic properties of a series of Ln2 and Ln4 hydroxo clusters. Dalton Trans 2018; 47:1726-1738. [DOI: 10.1039/c7dt00172j] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Tetra and di-nuclear Lanthanide hydroxo clusters have been synthesized and characterized magnetically.
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Affiliation(s)
| | - Chinmoy Das
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai
- India
| | - E. Carolina Sañudo
- Departament de Química Inorgànica i Institut de Nanociència i Nanotecnologia
- Universitat de Barcelona
- Barcelona
- Spain
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12
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Sasnovskaya VD, Kopotkov VA, Kazakova AV, Talantsev AD, Morgunov RB, Simonov SV, Zorina LV, Mironov VS, Yagubskii EB. Slow magnetic relaxation in mononuclear complexes of Tb, Dy, Ho and Er with the pentadentate (N3O2) Schiff-base dapsc ligand. NEW J CHEM 2018. [DOI: 10.1039/c8nj01928b] [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
AC measurements revealed field-induced single-ion magnet behavior of Dy and Er Kramers ion complexes. The properties of complexes were rationalized by superposition CF model.
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Affiliation(s)
- Valentina D. Sasnovskaya
- Institute of Problems of Chemical Physics of Russian Academy of Sciences
- Chernogolovka
- Russian Federation
| | - Vyacheslav A. Kopotkov
- Institute of Problems of Chemical Physics of Russian Academy of Sciences
- Chernogolovka
- Russian Federation
| | - Anna V. Kazakova
- Institute of Problems of Chemical Physics of Russian Academy of Sciences
- Chernogolovka
- Russian Federation
| | - Artem D. Talantsev
- Institute of Problems of Chemical Physics of Russian Academy of Sciences
- Chernogolovka
- Russian Federation
| | - Roman B. Morgunov
- Institute of Problems of Chemical Physics of Russian Academy of Sciences
- Chernogolovka
- Russian Federation
| | - Sergey V. Simonov
- Institute of Solid State Physics of Russian Academy of Sciences
- Chernogolovka
- Russian Federation
| | - Leokadiya V. Zorina
- Institute of Solid State Physics of Russian Academy of Sciences
- Chernogolovka
- Russian Federation
| | - Vladimir S. Mironov
- Shubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics” of Russian Academy of Sciences
- Moscow
- Russian Federation
| | - Eduard B. Yagubskii
- Institute of Problems of Chemical Physics of Russian Academy of Sciences
- Chernogolovka
- Russian Federation
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13
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Mandal L, Biswas S, Cosquer G, Shen Y, Yamashita M. Anion-driven structures and SMM behavior of dinuclear terbium and ytterbium complexes. Dalton Trans 2018; 47:17493-17499. [DOI: 10.1039/c8dt04049d] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
SMM behavior is observed for [Ln2(HL)4(NO3)6] (Ln = Tb and Yb, HL = 8-hydroxyquinaldine) complexes having nine-coordinated lanthanide centres, whereas, [Ln2(HL)4Cl6]·2EtOH complexes, having hexa-coordinated lanthanide centres do not show any SMM property.
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Affiliation(s)
- Leena Mandal
- Department of Chemistry
- Graduate School of Science
- Tohoku University
- Sendai 980-8578
- Japan
| | - Soumava Biswas
- WPI Research Center
- Advanced Institute for Materials Research
- Tohoku University
- Sendai 980-8577
- Japan
| | - Goulven Cosquer
- Department of Chemistry
- Graduate School of Science
- Tohoku University
- Sendai 980-8578
- Japan
| | - Yongbing Shen
- Department of Chemistry
- Graduate School of Science
- Tohoku University
- Sendai 980-8578
- Japan
| | - Masahiro Yamashita
- Department of Chemistry
- Graduate School of Science
- Tohoku University
- Sendai 980-8578
- Japan
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14
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Mondal AK, Goswami T, Misra A, Konar S. Probing the Effects of Ligand Field and Coordination Geometry on Magnetic Anisotropy of Pentacoordinate Cobalt(II) Single-Ion Magnets. Inorg Chem 2017; 56:6870-6878. [PMID: 28561569 DOI: 10.1021/acs.inorgchem.7b00233] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In this work, the effects of ligand field strength as well as the metal coordination geometry on magnetic anisotropy of pentacoordinated CoII complexes have been investigated using a combined experimental and theoretical approach. For that, a strategic design and synthesis of three pentacoordinate CoII complexes [Co(bbp)Cl2]·(MeOH) (1), [Co(bbp)Br2]·(MeOH) (2), and [Co(bbp)(NCS)2] (3) has been achieved by using the tridentate coordination environment of the ligand in conjunction with the accommodating terminal ligands (i.e., chloride, bromide, and thiocyanate). Detailed magnetic studies disclose the occurrence of slow magnetic relaxation behavior of CoII centers with an easy-plane magnetic anisotropy. A quantitative estimation of ZFS parameters has been successfully performed by density functional theory (DFT) calculations. Both the sign and magnitude of ZFS parameters are prophesied well by this DFT method. The theoretical results also reveal that the α → β (SOMO-SOMO) excitation contributes almost entirely to the total ZFS values for all complexes. It is worth noting that the excitation pertaining to the most positive contribution to the ZFS parameter is the dxy → dx2-y2 excitation for complexes 1 and 2, whereas for complex 3 it is the dz2 → dx2-y2 excitation.
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Affiliation(s)
- Amit Kumar Mondal
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal , Bhopal Bypass Road, Bhauri, Bhopal 462066, Madhya Pradesh, India
| | - Tamal Goswami
- Department of Chemistry, University of North Bengal , Siliguri, Darjeeling 734013, West Bengal, India
| | - Anirban Misra
- Department of Chemistry, University of North Bengal , Siliguri, Darjeeling 734013, West Bengal, India
| | - Sanjit Konar
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal , Bhopal Bypass Road, Bhauri, Bhopal 462066, Madhya Pradesh, India
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