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Jabeur W, Korb M, Hamdi M, Holub M, Princík D, Zeleňák V, Sanchez-Coronilla A, Shalash M, Čižmár E, Naïli H. Structural, optical and magnetic properties of a new metal-organic Co II-based complex. RSC Adv 2024; 14:25048-25061. [PMID: 39135970 PMCID: PMC11317920 DOI: 10.1039/d4ra02149e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Accepted: 06/03/2024] [Indexed: 08/15/2024] Open
Abstract
A mononuclear cobalt(ii) complex [C5H8N3]2[CoCl4(C5H7N3)2] (I) was synthesized and structurally characterized. Single crystal X-ray diffraction analysis indicates that monometallic Co(ii) ions acted as coordination nodes in a distorted octahedral geometry, giving rise to a supramolecular architecture. The latter is made up of a ½ unit form composed of an anionic element [Co0.5Cl2(C5H7N3)]- and one 2-amino-4-methylpyrimidinium cation [C5H8N3]+. The crystalline arrangement of this compound adopts the sandwich form where inorganic parts are sandwiched between the organic sheets following the [100] direction. More information regarding the structure hierarchy has been supplied based on Hirshfeld surface analysis; the X⋯H (X = N, Cl) interactions play a crucial role in stabilizing the self-assembly process of I, complemented by the intervention of π⋯π electrostatic interaction created between organic entities. Thermal analyses were carried out to study the thermal behavior process. Static magnetic measurements and ab initio calculations of compound I revealed the easy-axis anisotropy character of the central Co(ii) ion. Two-channel field-induced slow-magnetic relaxation was observed; the high-frequency channel is characterized by underbarrier relaxation with U eff = 16.5 cm-1, and the low-frequency channel involves a direct relaxation process affected by the phonon-bottleneck effect.
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Affiliation(s)
- Wiem Jabeur
- Laboratory Physico Chemistry of the Solid State, Department of Chemistry, Faculty of Sciences of Sfax, Sfax University POBOX 1171 3000 Sfax Tunisia
| | - Marcus Korb
- The University of Western Australia, School of Molecular Sciences 35 Stirling Highway, Crawley Perth Western Australia 6009 Australia
| | - Mohamed Hamdi
- Department of Chemistry, College of Sciences and Arts Turaif, Northern Border University Arar Saudi Arabia
| | - Mariia Holub
- Institute of Physics, Faculty of Science, P. J. Šafárik University in Košice SK-041 54 Košice Slovakia
| | - Dávid Princík
- Department of Inorganic Chemistry, Faculty of Science, P. J. Šafárik University Košice SK-041 54 Slovakia
| | - Vladimír Zeleňák
- Department of Inorganic Chemistry, Faculty of Science, P. J. Šafárik University Košice SK-041 54 Slovakia
| | | | - Marwan Shalash
- Department of Chemistry, College of Sciences and Arts Turaif, Northern Border University Arar Saudi Arabia
| | - Erik Čižmár
- Institute of Physics, Faculty of Science, P. J. Šafárik University in Košice SK-041 54 Košice Slovakia
| | - Houcine Naïli
- Laboratory Physico Chemistry of the Solid State, Department of Chemistry, Faculty of Sciences of Sfax, Sfax University POBOX 1171 3000 Sfax Tunisia
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2
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Mikhailenko MV, Ivanov VV, Shestakov AF, Kuzmin AV, Khasanov SS, Otsuka A, Yamochi H, Kitagawa H, Konarev DV. Magnetic behavior and ground spin states for coordination {L·[M II(Hal) 2] 3} 3- assemblies (Hal = Cl or I) of radical trianion hexacyanohexaazatriphenylenes (L) with three coordinated high-spin Fe II ( S = 2) or Co II ( S = 3/2) centers. Dalton Trans 2023; 52:11222-11233. [PMID: 37525575 DOI: 10.1039/d3dt01571h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
A series of trianion assemblies of hexaazatriphenylenehexacarbonitrile {HAT(CN)6} and hexaazatrinaphthylenehexacarbonitrile {HATNA(CN)6} with three Fe(II) or Co(II) ions: {cryptand(K+)}3·{HATNA(CN)6·(FeIII2)3}3-·2C6H4Cl2 (1), {cryptand(K+)}3·{HATNA(CN)6·(CoIII2)3}3-·2C6H4Cl2 (2), and (CV+)3·{HAT(CN)6·(CoIICl2)3}3-·0.5(CVCl)·2.5C6H4Cl2 (3) are synthesized (CVCl = crystal violet). Salt 1 has a χMT value of 9.80 emu K mol-1 at 300 K, indicating a contribution of three high-spin FeII (S = 2) and one S = 1/2 of HATNA(CN)6˙3-. The χMT value increases with cooling up to 12.92 emu K mol-1 at 28 K, providing a positive Weiss temperature of +20 K. Such behavior is described using a strong antiferromagnetic coupling between S = 2 and S = 1/2 with J1 = -82.1 cm-1 and a weaker FeII-FeII antiferromagnetic coupling with J2 = -7.0 cm-1. As a result, the spins of three Fe(II) ions (S = 2) align parallel to each other forming a high-spin S = 11/2 system. Density functional theory (DFT) calculations support a high-spin state of CoII (S = 3/2) for 2 and 3. However, the χMT value of 2 and 3 is 2.25 emu K mol-1 at 300 K, which is smaller than 6 emu K mol-1 calculated for the system with three independent S = 3/2 and one S = 1/2 spins. In contrast to 1, the χMT values decrease with cooling to 0.13-0.36 emu K mol-1 at 1.9 K, indicating that spins of cobalt atoms align antiparallel to each other. Data fitting using PHI software for the model consisting of three high-spin Co(II) ions and an S = 1/2 radical ligand shows very large CoII-L˙3- coupling for 2 and 3 with J1 values of -442 and -349 cm-1. The CoII-CoII coupling via the ligand (J2) is also large, being -100 and -84 cm-1, respectively, which is more than 10 times larger than that of 1. One of the reasons for the J2 increase may be the shortening of the Co-N(L) bonds in 3 and 2 to 2.02(2) and 1.993(12) Å. DFT calculations support the population of the quartet state for the Co3 system, whereas the high-spin decet (S = 9/2) state is positioned higher by 680 cm-1 and is not populated at 300 K. This is explained by the large CoII-CoII coupling. Thus, a balance between J1 and J2 couplings provides parallel or antiparallel alignment of the FeII and CoII spins, leading to high- or low-spin ground states of {L·[MII(Hal)2]3}3-.
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Affiliation(s)
- Maxim V Mikhailenko
- Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAS, Chernogolovka, Moscow region, 142432, Russia.
| | - Vladislav V Ivanov
- Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAS, Chernogolovka, Moscow region, 142432, Russia.
- Moscow State University, Leninskie Gory, Moscow, 119991 Russia
| | - Alexander F Shestakov
- Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAS, Chernogolovka, Moscow region, 142432, Russia.
- Moscow State University, Leninskie Gory, Moscow, 119991 Russia
| | - Aleksey V Kuzmin
- Institute of Solid State Physics RAS, Chernogolovka, Moscow region, 142432 Russia
| | - Salavat S Khasanov
- Institute of Solid State Physics RAS, Chernogolovka, Moscow region, 142432 Russia
| | - Akihiro Otsuka
- Division of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideki Yamochi
- Division of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hiroshi Kitagawa
- Division of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Dmitri V Konarev
- Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAS, Chernogolovka, Moscow region, 142432, Russia.
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3
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Pohle MH, Böhme M, Lohmiller T, Ziegenbalg S, Blechschmidt L, Görls H, Schnegg A, Plass W. Magnetic Anisotropy and Relaxation of Pseudotetrahedral [N 2 O 2 ] Bis-Chelate Cobalt(II) Single-Ion Magnets Controlled by Dihedral Twist Through Solvomorphism. Chemistry 2023; 29:e202202966. [PMID: 36468847 DOI: 10.1002/chem.202202966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 12/04/2022] [Accepted: 12/05/2022] [Indexed: 12/07/2022]
Abstract
The methanol solvomorph 1 ⋅ 2MeOH of the cobalt(II) complex [Co(LSal,2-Ph )2 ] (1) with the sterically demanding Schiff-base ligand 2-(([1,1'-biphenyl]-2-ylimino)methyl)phenol (HLSal,2-Ph ) shows the thus far largest dihedral twist distortion between the two chelate planes compared to an ideal pseudotetrahedral arrangement. The cobalt(II) ion in 1 ⋅ 2MeOH exhibits an easy-axis anisotropy leading to a spin-reversal barrier of 55.3 cm-1 , which corresponds to an increase of about 17 % induced by the larger dihedral twist compared to the solvent-free complex 1. The magnetic relaxation for 1 ⋅ 2MeOH is significantly slower compared to 1. An in-depth frequency-domain Fourier-transform (FD-FT) THz-EPR study not only allowed the direct measurement of the magnetic transition between the two lowest Kramers doublets for the cobalt(II) complexes, but also revealed the presence of spin-phonon coupling. Interestingly, a similar dihedral twist correlation is also observed for a second pair of cobalt(II)-based solvomorphs, which could be benchmarked by FD-FT THz-EPR.
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Affiliation(s)
- Maximilian H Pohle
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstraße 8, 07743, Jena, Germany
| | - Michael Böhme
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstraße 8, 07743, Jena, Germany
| | - Thomas Lohmiller
- EPR4Energy Joint Lab, Department Spins in Energy Conversion and Quantum Information Science, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Str. 16, 12489, Berlin, Germany.,present address: Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489, Berlin, Germany
| | - Sven Ziegenbalg
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstraße 8, 07743, Jena, Germany
| | - Louis Blechschmidt
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstraße 8, 07743, Jena, Germany
| | - Helmar Görls
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstraße 8, 07743, Jena, Germany
| | - Alexander Schnegg
- EPR4Energy Joint Lab, Department Spins in Energy Conversion and Quantum Information Science, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Str. 16, 12489, Berlin, Germany.,EPR Research Group, MPI for Chemical Energy Conversion, Stiftstr. 34-36, 45470, Mülheim an der Ruhr, Germany
| | - Winfried Plass
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstraße 8, 07743, Jena, Germany
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Böhme M, Rams M, Krebs C, Mangelsen S, Jess I, Plass W, Näther C. Co(NCS) 2 Chain Compound with Alternating 5- and 6-Fold Coordination: Influence of Metal Coordination on the Magnetic Properties. Inorg Chem 2022; 61:16841-16855. [PMID: 36218356 DOI: 10.1021/acs.inorgchem.2c02813] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reaction of Co(NCS)2 with 3-bromopyridine leads to the formation of discrete complexes [Co(NCS)2(3-bromopyridine)4] (1), [Co(NCS)2(3-bromopyridine)2(H2O)2] (2), and [Co(NCS)2(3-bromopyridine)2(MeOH)2] (3) depending on the solvent. Thermogravimetric measurements on 2 and 3 show a transformation into [Co(NCS)2(3-bromopyridine)2]n (4), which upon further heating is converted to [{Co(NCS)2}2(3-bromopyridine)3]n (5), whereas 1 transforms directly into 5 upon heating. Compound 5 can also be obtained from solution, which is not possible for 4. In 4 and 5, the cobalt(II) cations are linked by pairs of μ-1,3-bridging thiocyanate anions into chains. In compound 4, all cobalt(II) cations are octahedrally coordinated (OC-6), as is usually observed in such compounds, whereas in 5, a previously unkown alternating 5- and 6-fold coordination is observed, leading to vacant octahedral (vOC-5) and octahedral (OC-6) environments, respectively. In contrast to 4, the chains in 5 are very efficiently packed and linked by π···π stacking of the pyridine rings and interchain Co···Br interactions, which is the basis for the formation of this unusual chain. The spin chains in 4 demonstrate ferromagnetic intrachain exchange and much weaker interchain interactions, as is usually observed for such linear chain compounds. In contrast, compound 5 shows almost single-ion-like magnetic susceptibility, but the magnetic ordering temperature deduced from specific heat measurements is twice as high as that in 4, which might originate from π···π stacking and Co···Br interactions between neighboring chains. More importantly, unlike all linear Co(NCS)2 chain compounds, a dominant antiferromagnetic exchange is observed for 5, which is explained by density functional theory calculations predicting an alternating ferro- and aniferromagnetic exchange within the chains. Theoretical calculations on the two different cobalt(II) ions present in 5 predict an easy-axis anisotropy that is much stronger for the octahedral cobalt(II) ion than for the one with the vacant octahedral coordination, with the magnetic axes of the two ions being canted by an angle of 84°. This almost orthogonal orientation of the easy axis of magnetization for the two cobalt(II) ions is the rationale for the observed non-Ising behavior of 5.
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Affiliation(s)
- Michael Böhme
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstraße 8, Jena 07743, Germany
| | - Michał Rams
- Institute of Physics, Jagiellonian University, Łojasiewicza 11, Kraków 30348, Poland
| | - Christoph Krebs
- Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel, Max-Eyth-Straße 2, Kiel 24118, Germany
| | - Sebastian Mangelsen
- Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel, Max-Eyth-Straße 2, Kiel 24118, Germany
| | - Inke Jess
- Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel, Max-Eyth-Straße 2, Kiel 24118, Germany
| | - Winfried Plass
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstraße 8, Jena 07743, Germany
| | - Christian Näther
- Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel, Max-Eyth-Straße 2, Kiel 24118, Germany
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5
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Chen Y, Yang Q, Peng G, Zhang YQ, Ren XM. Influence of F-position and solvent on coordination geometry and single ion magnet behavior of Co(II) complexes. Dalton Trans 2021; 50:13830-13840. [PMID: 34522941 DOI: 10.1039/d1dt02148f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Three mononuclear Co(II) complexes with the compositions of [Co(L1)2] (1), [Co(L2)2(CH3CN)] (2) and [Co(L3)2] (3) (HL1 = 2-((E)-(2-fluorobenzylimino)methyl)-4,6-dibromophenol, HL2 = 2-((E)-(3-fluorobenzylimino)methyl)-4,6-dibromophenol and HL3 = 2-((E)-(4-fluorobenzylimino)methyl)-4,6-dibromophenol) were prepared and structurally determined. The changes in the F-positions in the ligands and solvents led to the formation of these products with various coordination geometries. Both complexes 1 and 3 are four-coordinated and their coordination geometries can be described as tetrahedron and seesaw, whereas complex 2 is five coordinated with a coordination configuration in between trigonal bipyramid and square pyramid. Static magnetic studies reveal that all these complexes exhibit considerable easy-axis magnetic anisotropy. The easy-axis magnetic anisotropy of 1 and 3 mainly derives from the first quartet excited state, whereas that of 2 primarily originates from the first, third and fourth quartet excited states established by theoretical calculations. All the resulting complexes display field-induced slow magnetic relaxation. Complex 3 represents the first Co(II) single ion magnet with a seesaw coordination geometry. Ab initio calculations predict that the magnetic anisotropy will enhance when the seesaw coordination geometry varies from distortion to regulation.
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Affiliation(s)
- Yue Chen
- School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, P. R. China.
| | - Qi Yang
- School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, P. R. China.
| | - Guo Peng
- School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, P. R. China.
| | - Yi-Quan Zhang
- Jiangsu Key Laboratory for NSLSCS, School of Physical Science and Technology, Nanjing Normal University, Nanjing 210023, P. R. China.
| | - Xiao-Ming Ren
- School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, P. R. China.
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Wang M, Xu H, Sun T, Cui H, Zhang YQ, Chen L, Tang Y. Optimal N–Co–N bite angle for enhancing the magnetic anisotropy of zero-field Co(II) single-ion magnets in tetrahedral [N4] coordination environment. J SOLID STATE CHEM 2021. [DOI: 10.1016/j.jssc.2021.122209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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7
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Akintola O, Buchholz A, Görls H, Plass W. Modulator Induced Formation of a Neutral Framework Based on Trinuclear Cobalt(II) Clusters and Nitrilotribenzoic Acid: Synthesis, Magnetism, and Sorption Properties. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Oluseun Akintola
- Institut für Anorganische und Analytische Chemie Friedrich-Schiller-Universität Jena Humboldtstr. 8 07743 Jena Germany
| | - Axel Buchholz
- Institut für Anorganische und Analytische Chemie Friedrich-Schiller-Universität Jena Humboldtstr. 8 07743 Jena Germany
| | - Helmar Görls
- Institut für Anorganische und Analytische Chemie Friedrich-Schiller-Universität Jena Humboldtstr. 8 07743 Jena Germany
| | - Winfried Plass
- Institut für Anorganische und Analytische Chemie Friedrich-Schiller-Universität Jena Humboldtstr. 8 07743 Jena Germany
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8
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Antkowiak M, Majee MC, Maity M, Mondal D, Kaj M, Lesiów M, Bieńko A, Kronik L, Chaudhury M, Kamieniarz G. Generalized Heisenberg-Type Magnetic Phenomena in Coordination Polymers with Nickel–Lanthanide Dinuclear Units. THE JOURNAL OF PHYSICAL CHEMISTRY C 2021; 125:11182-11196. [DOI: 10.1021/acs.jpcc.1c01947] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/19/2023]
Affiliation(s)
- Michał Antkowiak
- Faculty of Physics, A. Mickiewicz University, ul. Uniwersytetu Poznańskiego 2, 61-614 Poznań, Poland
| | - Mithun Chandra Majee
- Banwarilal Bhalotia College, Kazi Nazrul University, Asansol, West Bengal-713303, India
| | - Manoranjan Maity
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
| | - Dhrubajyoti Mondal
- Department of Chemistry, Government General Degree College Mangalkote, University of Burdwan, Burdwan, West Bengal-713143, India
| | - Michalina Kaj
- Faculty of Chemistry, University of Wroclaw, 14 F. Joliot-Curie, 50-383 Wroclaw, Poland
| | - Monika Lesiów
- Faculty of Chemistry, University of Wroclaw, 14 F. Joliot-Curie, 50-383 Wroclaw, Poland
| | - Alina Bieńko
- Faculty of Chemistry, University of Wroclaw, 14 F. Joliot-Curie, 50-383 Wroclaw, Poland
| | - Leeor Kronik
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovoth 7610000, Israel
| | - Muktimoy Chaudhury
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
| | - Grzegorz Kamieniarz
- Faculty of Physics, A. Mickiewicz University, ul. Uniwersytetu Poznańskiego 2, 61-614 Poznań, Poland
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovoth 7610000, Israel
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9
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Banerjee A, Banerjee S, Gómez García CJ, Benmansour S, Chattopadhyay S. Field-induced single molecule magnet behavior of a dinuclear cobalt(II) complex: a combined experimental and theoretical study. Dalton Trans 2020; 49:16778-16790. [PMID: 33174540 DOI: 10.1039/d0dt02158j] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two dinuclear cobalt(ii) complexes, [(dmso)CoIIL1(μ-(m-NO2)C6H4COO)CoII(NCS)] (1) and [(dmso)CoIIL2(μ-(m-NO2)C6H4COO)CoII(NCS)] (2) [dmso = dimethylsulfoxide, H2L1 = (2,2-dimethyl-1,3-propanediyl)bis(iminomethylene)bis(6-methoxyphenol) and H2L2 = (2,2-dimethyl-1,3-propanediyl)bis(iminomethylene)bis(6-ethoxyphenol)] have been synthesized and structurally characterized by single-crystal X-ray diffraction, magnetic-susceptibility measurements and various spectroscopic techniques. Each complex contains a cobalt(ii) center with a slightly distorted octahedral geometry and a second cobalt(ii) center with a distorted trigonal prismatic one. To obtain insight into the physical nature of weak non-covalent interactions, we have extensively used the Bader's quantum theory of atoms-in-molecules (QTAIM). In addition, the non-covalent interaction reduced density gradient (NCI-RDG) methods established the presence of such non-covalent intermolecular interactions. Variable temperature magnetic susceptibility measurements show that both cobalt centers in each complex are in the high spin state (S = 3/2) and both complexes show weak ferromagnetic couplings through the double phenoxido bridges (J = 3.36(3) cm-1 in 1 and 4.56(2) cm-1 in 2). The magnetic properties of both complexes can be fitted to a Co(ii) dimer model including similar orbital reduction factors (α = -0.94(1) for 1 and -0.85(1) for 2) although different zero field splitting parameters D(1) = 11.0(4) cm-1 and D(2) = 19.5(4) cm-1 in 1 and D(1) = 8.2(4) cm-1 and D(2) = -1.3(4) cm-1 in 2. AC magnetic measurements reveal that the CoII2 unit in complex 2 exhibits field-induced slow relaxation of the magnetization at low temperatures and high frequencies.
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Affiliation(s)
- Abhisek Banerjee
- Department of Chemistry, Inorganic Section, Jadavpur University, Kolkata - 700032, India.
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10
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Jochim A, Rams M, Böhme M, Ceglarska M, Plass W, Näther C. Thermodynamically metastable chain and stable layered Co(NCS) 2 coordination polymers: thermodynamic relations and magnetic properties. Dalton Trans 2020; 49:15310-15322. [PMID: 33118568 DOI: 10.1039/d0dt03227a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Reaction of Co(NCS)2 with 4-bromopyridine leads to the formation of discrete complexes with the composition Co(NCS)2(4-bromopyridine)4·(CH3CN)0.67 (1), Co(NCS)2(4-bromopyridine)2(H2O)2 (2), Co(NCS)2(4-bromopyridine)2(CH3OH)2 (3) and Co(NCS)2(4-bromopyridine)2(CH3CN)2 (4). Upon heating compounds 2 and 4 transform into a crystalline product with the composition Co(NCS)2(4-bromopyridine)2 (5-I) that also can easily be obtained from solution. In this compound, the Co cations are linked by single μ-1,3-bridging thiocyanate anions into layers. Thermal decomposition of 3 leads to a second isomer (5-II), which is thermodynamically metastable and can also be synthesized from solution under kinetic control. In contrast to 5-I, the Co cations are linked by pairs of anionic ligands into linear chains. The magnetic exchange is very weak in 5-I, but much stronger and ferromagnetic along the linear chains in 5-II. AF ordering in 5-II is reached at 3.05 K, and magnetic relaxation is observed at the metamagnetic transition with an Arrhenius barrier of 17.1(3) cm-1. Ab initio computational studies reveal a different type of magnetic anisotropy to be present in the two crystallographically - independent Co centers in 5-II.
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Affiliation(s)
- Aleksej Jochim
- Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel, Max-Eyth-Straße 2, 24118 Kiel, Germany.
| | - Michał Rams
- Institute of Physics, Jagiellonian University, Łojasiewicza 11, 30-348 Krakow, Poland
| | - Michael Böhme
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstr. 8, 07743 Jena, Germany
| | - Magdalena Ceglarska
- Institute of Physics, Jagiellonian University, Łojasiewicza 11, 30-348 Krakow, Poland
| | - Winfried Plass
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstr. 8, 07743 Jena, Germany
| | - Christian Näther
- Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel, Max-Eyth-Straße 2, 24118 Kiel, Germany.
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Saber MR, Przyojski JA, Tonzetich ZJ, Dunbar KR. Slow magnetic relaxation in cobalt N-heterocyclic carbene complexes. Dalton Trans 2020; 49:11577-11582. [PMID: 32749418 DOI: 10.1039/d0dt02286a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The combined experimental and theoretical investigation of the magnetic properties of the cobalt(ii) NHC complexes (NHC = N-heterocyclic carbene); [Co(CH2SiMe3)2(IPr)] (1), [CoCl2(IMes)2] (2) and [Co(CH3)2(IMes)2] (3) revealed a large easy plane anisotropy for 1 (D = +73.7 cm-1) and a moderate easy axis anisotropy for 2 (D = -7.7 cm-1) due to significant out-of-state spin-orbit coupling. Dynamic magnetic measurements revealed slow relaxation of the magnetization for 1 (Ueff = 22.5 K, τ0 = 3 × 10-7 s, 1000 Oe) and for 2 (Ueff = 20.2 K, τ0 = 1.73 × 10-8 s, 1500 Oe). The molecular origin of the slow relaxation phenomena was further supported by the retention of AC signal in 10% solutions in 2-MeTHF which reveals a second zero field AC signal in 1 at higher frequencies. Compound 3 was found to be an S = 1/2 system.
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Affiliation(s)
- Mohamed R Saber
- Department of Chemistry, Texas A&M University, College Station, TX 77842-3012, USA. and Chemistry Department, Faculty of Science, Fayoum University, Fayoum 63514, Egypt
| | - Jacob A Przyojski
- Department of Chemistry, University of Texas at San Antonio (UTSA), San Antonio, TX 78249, USA
| | - Zachary J Tonzetich
- Department of Chemistry, University of Texas at San Antonio (UTSA), San Antonio, TX 78249, USA
| | - Kim R Dunbar
- Department of Chemistry, Texas A&M University, College Station, TX 77842-3012, USA.
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12
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A combined experimental and theoretical study on an ionic cobalt(III/II) complex with a Schiff base ligand. Polyhedron 2020. [DOI: 10.1016/j.poly.2020.114432] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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13
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Świtlicka A, Machura B, Kruszynski R, Moliner N, Carbonell JM, Cano J, Lloret F, Julve M. Magneto-structural diversity of Co(ii) compounds with 1-benzylimidazole induced by linear pseudohalide coligands. Inorg Chem Front 2020. [DOI: 10.1039/d0qi00752h] [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 magneto-structural diversity of 1-benzylimidazole-containing cobalt(ii) compounds with linear pseudohalide ions (NCS−, NCO−, and N3−) is explored.
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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
| | - Rafał Kruszynski
- Department of X-ray Crystallography and Crystal Chemistry
- Institute of General and Ecological Chemistry
- Lodz University of Technology
- 90-924 Łodz
- Poland
| | - Nicolás Moliner
- Department of Química Inorgànica/Instituto de Ciencia Molecular (ICMol)
- Facultat de Quimica de la Universitat de València
- 46980 Paterna
- Spain
| | - José Miguel Carbonell
- Department of Química Inorgànica/Instituto de Ciencia Molecular (ICMol)
- Facultat de Quimica de la Universitat de València
- 46980 Paterna
- Spain
| | - Joan Cano
- Department of Química Inorgànica/Instituto de Ciencia Molecular (ICMol)
- Facultat de Quimica de la Universitat de València
- 46980 Paterna
- Spain
| | - 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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14
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Vallejo J, Viciano-Chumillas M, Lloret F, Julve M, Castro I, Krzystek J, Ozerov M, Armentano D, De Munno G, Cano J. Coligand Effects on the Field-Induced Double Slow Magnetic Relaxation in Six-Coordinate Cobalt(II) Single-Ion Magnets (SIMs) with Positive Magnetic Anisotropy. Inorg Chem 2019; 58:15726-15740. [PMID: 31738531 DOI: 10.1021/acs.inorgchem.9b01719] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two mononuclear cobalt(II) compounds of formula [Co(dmphen)2(OOCPh)]ClO4·1/2H2O·1/2CH3OH (1) and [Co(dmbipy)2(OOCPh)]ClO4 (2) (dmphen = 2,9-dimethyl-1,10-phenanthroline, dmbipy = 6,6'-dimethyl-2,2'-bipyridine and HOOCPh = benzoic acid) are prepared and magnetostructurally investigated. Each cobalt(II) ion is six-coordinate with a distorted octahedral CoN4O2 environment. The complex cations are interlinked leading to supramolecular chains (1) and pairs (2) that grow along the crystallographic c-axis with racemic mixtures of (Δ,Λ)-Co units. FIRMS allowed us to directly measure the zero-field splitting between the two lowest Kramers doublets, which led to axial anisotropy values of 58.3 cm-1 ≤ D < 60.7 cm-1 (1) and 63.8 cm-1 ≤ D < 64.1 cm-1 (2). HFEPR spectra of polycrystalline samples of 1 and 2 at low temperatures confirm the positive sign of D and provide an estimate of the E/D quotient [0.147/0.187 (1) and 0.052 (2)]. Detailed ac and dc magnetic studies reveal that 1 and 2 are new examples of field-induced single-ion magnets (SIMs) with small transversal anisotropy. CASSCF/NEVPT2 calculations support these results. Two Orbach processes or one Orbach plus a direct relaxation mechanism provide similar agreements with the nonlinear experimental Arrhenius plots at Hdc = 500 and 2500 G for 1. Two independent relaxation processes occur in 2, but in contrast to 1, an observed linear dependence of ln(τ) vs 1/T substantiates Orbach processes against the most widely proposed Raman and direct mechanisms. The analysis of each relaxation process in 2 provided values for Ea and τ0 that are very close to those found for 1, validating the predominant role of the Orbach relaxations in both compounds and, probably, also in other cobalt(II) SIMs. A mechanism based on a spin-phonon coupling is proposed to account for the SIM behavior in 1 and 2 with any Raman or direct processes being discarded.
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Affiliation(s)
- Julia Vallejo
- Institut de Ciència Molecular (ICMol) and Departament de Química Inorgànica , Universitat de València , 46980 Paterna , València
| | - Marta Viciano-Chumillas
- Institut de Ciència Molecular (ICMol) and Departament de Química Inorgànica , Universitat de València , 46980 Paterna , València
| | - Francisco Lloret
- Institut de Ciència Molecular (ICMol) and Departament de Química Inorgànica , Universitat de València , 46980 Paterna , València
| | - Miguel Julve
- Institut de Ciència Molecular (ICMol) and Departament de Química Inorgànica , Universitat de València , 46980 Paterna , València
| | - Isabel Castro
- Institut de Ciència Molecular (ICMol) and Departament de Química Inorgànica , Universitat de València , 46980 Paterna , València
| | - J Krzystek
- National High Magnetic Field Laboratory , Florida State University , Tallahassee , Florida 32310 , United States
| | - Mykhaylo Ozerov
- National High Magnetic Field Laboratory , Florida State University , Tallahassee , Florida 32310 , United States
| | - Donatella Armentano
- Dipartamento di Chimica e Tecnologie Chimiche , Università della Calabria , 87036 Rende , Cosenza Italy
| | - Giovanni De Munno
- Dipartamento di Chimica e Tecnologie Chimiche , Università della Calabria , 87036 Rende , Cosenza Italy
| | - Joan Cano
- Institut de Ciència Molecular (ICMol) and Departament de Química Inorgànica , Universitat de València , 46980 Paterna , València
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15
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Böhme M, Plass W. How to link theory and experiment for single-chain magnets beyond the Ising model: magnetic properties modeled from ab initio calculations of molecular fragments. Chem Sci 2019; 10:9189-9202. [PMID: 32055306 PMCID: PMC6979495 DOI: 10.1039/c9sc02735a] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 08/15/2019] [Indexed: 12/23/2022] Open
Abstract
Magnetic properties of coordination polymers like single-chain magnets (SCMs) are based on magnetic domains, which are formed due to magnetic exchange between neighboring anisotropic spin centers. However, the computational restrictions imposed by the high level of theory needed for an adequate ab initio quantum mechanical treatment on the basis of multi-reference methods for these systems limit the feasibility of such calculations to mononuclear fragments as appropriate structural cutouts for the metal centers along the chains. Hence, results from such calculations describe single-ion properties and cannot be directly correlated with experimental data representing magnetic domains. We present a theoretical approach based on n-membered Ising-spin rings with n = 3-12, which allows us to simulate magnetic domains and to derive important magnetic properties for SCM compounds. Magnetic exchange, which is not provided by calculations of mononuclear fragments, is obtained by fitting the theoretical magnetic susceptibility against experimental data. The presented approach is tested for cobalt(ii)-based SCMs with three types of repeating sequences, which differ in nuclearity and symmetry. The magnetic parameters derived using the presented approach were found to be in good agreement with the experimental data. Moreover, the energy spectra obtained for the three test cases using the presented approach are characteristic of a deviation of the individual systems from the ideal Ising behavior. An extrapolation technique towards larger systems (n > 12) is presented which can provide information on the statistical mean length of the magnetic domains in the three investigated SCM compounds.
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Affiliation(s)
- Michael Böhme
- Institut für Anorganische und Analytische Chemie , Friedrich-Schiller-Universität Jena , Humboldtstraße 8 , 07743 Jena , Germany . ; ; Tel: +49 3641 948130
| | - Winfried Plass
- Institut für Anorganische und Analytische Chemie , Friedrich-Schiller-Universität Jena , Humboldtstraße 8 , 07743 Jena , Germany . ; ; Tel: +49 3641 948130
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16
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Kong JJ, Shao D, Zhang JC, Jiang YX, Ji CL, Huang XC. From mononuclear to two-dimensional cobalt(ii) complexes based on a mixed benzimidazole–dicarboxylate strategy: syntheses, structures, and magnetic properties. CrystEngComm 2019. [DOI: 10.1039/c8ce01931b] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Three cobalt(ii) complexes with diverse structure dimensions based on a mixed benzimidazole–dicarboxylate strategy have been synthesized hydrothermally and characterized structurally and magnetically.
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Affiliation(s)
- Jiao-Jiao Kong
- School of Chemistry and Environmental Engineering
- Yancheng Teachers University
- Yancheng
- China
| | - Dong Shao
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing
- China
| | - Jia-Chen Zhang
- School of Chemistry and Environmental Engineering
- Yancheng Teachers University
- Yancheng
- China
| | - Yu-Xuan Jiang
- School of Chemistry and Environmental Engineering
- Yancheng Teachers University
- Yancheng
- China
| | - Cheng-Long Ji
- School of Chemistry and Environmental Engineering
- Yancheng Teachers University
- Yancheng
- China
| | - Xing-Cai Huang
- School of Chemistry and Environmental Engineering
- Yancheng Teachers University
- Yancheng
- China
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17
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Tupolova YP, Shcherbakov IN, Popov LD, Lebedev VE, Tkachev VV, Zakharov KV, Vasiliev AN, Korchagin DV, Palii AV, Aldoshin SM. Field-induced single-ion magnet behaviour of a hexacoordinated Co(ii) complex with easy-axis-type magnetic anisotropy. Dalton Trans 2019; 48:6960-6970. [DOI: 10.1039/c9dt00770a] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This study presents the novel hexacoordinated Co(ii) mononuclear complex with SIM behavior.
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Affiliation(s)
- Yulia P. Tupolova
- Department of Chemistry
- Southern Federal University
- Rostov-on-Don
- Russia
| | | | - Leonid D. Popov
- Department of Chemistry
- Southern Federal University
- Rostov-on-Don
- Russia
| | | | - Valery V. Tkachev
- Institute of Problems of Chemical Physics of the Russian Academy of Sciences
- Moscow Region
- Russia
| | | | - Alexander N. Vasiliev
- Physics Faculty
- M.V. Lomonosov Moscow State University
- Moscow 119991
- Russia
- National University of Science and Technology “MISiS”
| | - Denis V. Korchagin
- Institute of Problems of Chemical Physics of the Russian Academy of Sciences
- Moscow Region
- Russia
| | - Andrei V. Palii
- Institute of Problems of Chemical Physics of the Russian Academy of Sciences
- Moscow Region
- Russia
- Institute of Applied Physics
- Chisinau
| | - Sergey M. Aldoshin
- Institute of Problems of Chemical Physics of the Russian Academy of Sciences
- Moscow Region
- Russia
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18
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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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19
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Zhai YQ, Deng YF, Zheng YZ. Pseudotetrahedral cobalt(ii) complexes with PNP-ligands showing uniaxial magnetic anisotropy. Dalton Trans 2018; 47:8874-8878. [PMID: 29922787 DOI: 10.1039/c8dt01683f] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Two mononuclear pseudotetrahedral cobalt(ii) complexes with the formula Co(PNP)X2, where X = Cl (1) or X = SCN (2) and PNP = bis(2-(diphenylphosphaneyl)-4-methylphenyl)amine, have been synthesised. Magnetic and high-frequency/field electron paramagnetic resonance (HF-EPR) spectroscopy and ab initio calculation studies reveal that both complexes show uniaxial magnetic anisotropy.
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Affiliation(s)
- Yuan-Qi Zhai
- Frontier Institute of Science and Technology (FIST), State Key Laboratory for Mechanical Behavior of Materials, MOE Key Laboratory for Nonequilibrium Synthesis of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy and Materials Chemistry and School of Science, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi 710054, P. R. China.
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20
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Zhou J, Song J, Yuan A, Wang Z, Chen L, Ouyang ZW. Slow magnetic relaxation in two octahedral cobalt(II) complexes with positive axial anisotropy. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2018.04.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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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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22
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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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23
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Gupta T, Rajaraman G. Modelling spin Hamiltonian parameters of molecular nanomagnets. Chem Commun (Camb) 2018; 52:8972-9008. [PMID: 27366794 DOI: 10.1039/c6cc01251e] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Molecular nanomagnets encompass a wide range of coordination complexes possessing several potential applications. A formidable challenge in realizing these potential applications lies in controlling the magnetic properties of these clusters. Microscopic spin Hamiltonian (SH) parameters describe the magnetic properties of these clusters, and viable ways to control these SH parameters are highly desirable. Computational tools play a proactive role in this area, where SH parameters such as isotropic exchange interaction (J), anisotropic exchange interaction (Jx, Jy, Jz), double exchange interaction (B), zero-field splitting parameters (D, E) and g-tensors can be computed reliably using X-ray structures. In this feature article, we have attempted to provide a holistic view of the modelling of these SH parameters of molecular magnets. The determination of J includes various class of molecules, from di- and polynuclear Mn complexes to the {3d-Gd}, {Gd-Gd} and {Gd-2p} class of complexes. The estimation of anisotropic exchange coupling includes the exchange between an isotropic metal ion and an orbitally degenerate 3d/4d/5d metal ion. The double-exchange section contains some illustrative examples of mixed valance systems, and the section on the estimation of zfs parameters covers some mononuclear transition metal complexes possessing very large axial zfs parameters. The section on the computation of g-anisotropy exclusively covers studies on mononuclear Dy(III) and Er(III) single-ion magnets. The examples depicted in this article clearly illustrate that computational tools not only aid in interpreting and rationalizing the observed magnetic properties but possess the potential to predict new generation MNMs.
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Affiliation(s)
- Tulika Gupta
- Department of Chemistry, IIT Powai, Mumbai-400076, India.
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24
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Böhme M, Ziegenbalg S, Aliabadi A, Schnegg A, Görls H, Plass W. Magnetic relaxation in cobalt(ii)-based single-ion magnets influenced by distortion of the pseudotetrahedral [N2O2] coordination environment. Dalton Trans 2018; 47:10861-10873. [DOI: 10.1039/c8dt01530a] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Cobalt(ii) complexes with different dihedral angles between the bidentate ligands show a significant variation in their magnetic relaxation behavior.
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Affiliation(s)
- Michael Böhme
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität Jena
- 07745 Jena
- Germany
| | - Sven Ziegenbalg
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität Jena
- 07745 Jena
- Germany
| | - Azar Aliabadi
- Berlin Joint EPR Lab
- Institute for Nanospectroscopy
- Helmholtz-Zentrum Berlin für Materialien und Energie
- 12489 Berlin
- Germany
| | - Alexander Schnegg
- Berlin Joint EPR Lab
- Institute for Nanospectroscopy
- Helmholtz-Zentrum Berlin für Materialien und Energie
- 12489 Berlin
- Germany
| | - Helmar Görls
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität Jena
- 07745 Jena
- Germany
| | - Winfried Plass
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität Jena
- 07745 Jena
- Germany
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25
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Doroshenko I, Babiak M, Buchholz A, Görls H, Plass W, Pinkas J. New molecular heptanuclear cobalt phosphonates: synthesis, structures and magnetic properties. NEW J CHEM 2018. [DOI: 10.1039/c8nj00902c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Synthesis, structures and magnetic properties (strong anisotropy, ferromagnetic and antiferromagnetic interactions) of novel {Co7} homoleptic molecular cobalt phosphonates with a similar structure motif are described.
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Affiliation(s)
- Iaroslav Doroshenko
- Department of Chemistry
- Masaryk University
- CZ-61137 Brno
- Czech Republic
- CEITEC MU
| | - Michal Babiak
- Department of Chemistry
- Masaryk University
- CZ-61137 Brno
- Czech Republic
- CEITEC MU
| | - Axel Buchholz
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität Jena
- 07743 Jena
- Germany
| | - Helmar Görls
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität Jena
- 07743 Jena
- Germany
| | - Winfried Plass
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität Jena
- 07743 Jena
- Germany
| | - Jiri Pinkas
- Department of Chemistry
- Masaryk University
- CZ-61137 Brno
- Czech Republic
- CEITEC MU
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26
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Plaul D, Böhme M, Ostrovsky S, Tomkowicz Z, Görls H, Haase W, Plass W. Modeling Spin Interactions in a Triangular Cobalt(II) Complex with Triaminoguanidine Ligand Framework: Synthesis, Structure, and Magnetic Properties. Inorg Chem 2017; 57:106-119. [DOI: 10.1021/acs.inorgchem.7b02229] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daniel Plaul
- Institut für
Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstr. 8, 07743 Jena, Germany
| | - Michael Böhme
- Institut für
Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstr. 8, 07743 Jena, Germany
| | - Serghei Ostrovsky
- Institute of Applied Physics, Academy of Sciences of Moldova, Academiei str.5, MD-2028, Chisinau, Moldova
| | - Zbigniew Tomkowicz
- Institute of Physics, Jagiellonian University, Łojasiewicza 11, 30-348 Krakow, Poland
| | - Helmar Görls
- Institut für
Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstr. 8, 07743 Jena, Germany
| | - Wolfgang Haase
- Eduard-Zintl-Institute
of Inorganic and Physical Chemistry, Darmstadt University of Technology, Alarich-Weiss-Str. 4, 64287 Darmstadt, Germany
| | - Winfried Plass
- Institut für
Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstr. 8, 07743 Jena, Germany
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27
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Nandy M, Saha A, Shit S. Synthesis, characterization, and crystal structure of a four-coordinate cobalt(II) compound incorporating bis(3,5-dimethylpyrazol-1-yl)methane and cyanate. INORG NANO-MET CHEM 2017. [DOI: 10.1080/24701556.2017.1284123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Madhusudan Nandy
- Department of Basic Engineering Science & Humanities, Netaji Subhash Engineering College, Panchpota, Garia, India
| | - Arindam Saha
- Department of Chemistry, Jalpaiguri Government Engineering College, Jalpaiguri, India
- Department of Physics, Jalpaiguri Government Engineering College, Jalpaiguri, India
| | - Shyamapada Shit
- Department of Chemistry, Jalpaiguri Government Engineering College, Jalpaiguri, India
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28
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Palion-Gazda J, Machura B, Kruszynski R, Grancha T, Moliner N, Lloret F, Julve M. Spin Crossover in Double Salts Containing Six- and Four-Coordinate Cobalt(II) Ions. Inorg Chem 2017; 56:6281-6296. [DOI: 10.1021/acs.inorgchem.7b00360] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Joanna Palion-Gazda
- Department of Crystallography, Institute of Chemistry, University of Silesia, Ninth Szkolna Street, 40006 Katowice, Poland
| | - Barbara Machura
- Department of Crystallography, Institute of Chemistry, University of Silesia, Ninth Szkolna Street, 40006 Katowice, Poland
| | - Rafal Kruszynski
- Department of X-ray Crystallography and Crystal Chemistry, Institute
of General and Ecological Chemistry, Lodz University of Technology, 116 Żeromski Street, 90-924 Łódź, Poland
| | - Thais Grancha
- Departament de Química Inorgànica/Instituto de Ciencia
Molecular (ICMol), Universitat de València, C/Catedrático José
Beltrán 2, 46980 Paterna, València, Spain
| | - Nicolás Moliner
- Departament de Química Inorgànica/Instituto de Ciencia
Molecular (ICMol), Universitat de València, C/Catedrático José
Beltrán 2, 46980 Paterna, València, Spain
| | - Francesc Lloret
- Departament de Química Inorgànica/Instituto de Ciencia
Molecular (ICMol), Universitat de València, C/Catedrático José
Beltrán 2, 46980 Paterna, València, Spain
| | - Miguel Julve
- Departament de Química Inorgànica/Instituto de Ciencia
Molecular (ICMol), Universitat de València, C/Catedrático José
Beltrán 2, 46980 Paterna, València, Spain
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29
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Peng Y, Mereacre V, Anson CE, Zhang Y, Bodenstein T, Fink K, Powell AK. Field-Induced Co(II) Single-Ion Magnets with mer-Directing Ligands but Ambiguous Coordination Geometry. Inorg Chem 2017; 56:6056-6066. [PMID: 28485955 DOI: 10.1021/acs.inorgchem.6b02743] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Three air-stable Co(II) mononuclear complexes with different aromatic substituents have been prepared and structurally characterized by single-crystal X-ray diffraction. The mononuclear complexes [Co(H2L1)2]·2THF (1), [Co(HL2)2] (2), and [Co(H2L3)2]·CH2Cl2 (3) (where H3L1, H2L2, and H3L3 represent 3-hydroxy-naphthalene-2-carboxylic acid (6-hydroxymethyl-pyridin-2-ylmethylene) hydrazide, nicotinic acid (6-hydroxymethyl-pyridin-2-ylmethylene) hydrazide, and 2-hydroxy-benzoic acid (6-hydroxymethyl-pyridin-2-ylmethylene) hydrazide, respectively) feature a distorted mer octahedral coordination geometry. Detailed magnetic studies of 1-3 have been conducted using direct and alternating current magnetic susceptibility data. Field-induced slow magnetic relaxation was observed for these three complexes. There are few examples of such behavior in (distorted) octahedral coordination geometry (OC) Co(II) mononuclear complexes with uniaxial anisotropy. Analysis of the six-coordinate Co(II) mononuclear single-ion magnets (SIMs) in the literature using the SHAPE program revealed that they all show what is best described as distorted trigonal prismatic (TRP) coordination geometry, and in general, these show negative D zero-field splitting (ZFS) values. On the other hand, all the Co(II) mononuclear complexes displaying what is best approximated as distorted octahedral (OC) coordination geometry show positive D values. In the new Co(II) mononuclear complexes we describe here, there is an ambiguity, since the rigid tridentate ligands confer what is best described for an octahedral complex as a mer coordination geometry, but the actual shape of the first coordination sphere is between octahedral and trigonal prismatic. The negative D values observed experimentally and supported by high-level electronic structure calculations are thus in line with a trigonal prismatic geometry. However, a consideration of the rhombicity as indicated by the E value of the ZFS in conjunction with the SHAPE analysis shows that in this case it is difficult to distinguish between the OC and TRP descriptions.
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Affiliation(s)
- Yan Peng
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology , Engesserstrasse 15, 76131 Karlsruhe, Germany.,Institute of Nanotechnology, Karlsruhe Institute of Technology , Postfach 3640, 76021 Karlsruhe, Germany
| | - Valeriu Mereacre
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology , Engesserstrasse 15, 76131 Karlsruhe, Germany
| | - Christopher E Anson
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology , Engesserstrasse 15, 76131 Karlsruhe, Germany
| | - Yiquan Zhang
- Jiangsu Key Laboratory for NSLSCS, School of Physical Science and Technology, Nanjing Normal University , 210023 Nanjing, China
| | - Tilmann Bodenstein
- qLEAP Center fpr Theoretical Chemistry, Department of Chemistry, Aarhus University , Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Karin Fink
- Institute of Nanotechnology, Karlsruhe Institute of Technology , Postfach 3640, 76021 Karlsruhe, Germany
| | - Annie K Powell
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology , Engesserstrasse 15, 76131 Karlsruhe, Germany.,Institute of Nanotechnology, Karlsruhe Institute of Technology , Postfach 3640, 76021 Karlsruhe, Germany
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30
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Peters GM, Winegrad JB, Gau MR, Imler GH, Xu B, Ren S, Wayland BB, Zdilla MJ. Synthesis and Structure of 2,5-Bis[N-(2,6-mesityl)iminomethyl]pyrrolylcobalt(II): Evidence for One-Electron-Oxidized, Redox Noninnocent Ligand Behavior. Inorg Chem 2017; 56:3377-3385. [DOI: 10.1021/acs.inorgchem.6b02898] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Garvin M. Peters
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Jacob B. Winegrad
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Michael R. Gau
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Gregory H. Imler
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Beibei Xu
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Shenqiang Ren
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Bradford B. Wayland
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Michael J. Zdilla
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
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31
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Bruno R, Vallejo J, Marino N, De Munno G, Krzystek J, Cano J, Pardo E, Armentano D. Cytosine Nucleobase Ligand: A Suitable Choice for Modulating Magnetic Anisotropy in Tetrahedrally Coordinated Mononuclear CoII Compounds. Inorg Chem 2017; 56:1857-1864. [DOI: 10.1021/acs.inorgchem.6b02448] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Rosaria Bruno
- Dipartimento di
Chimica e Tecnologie Chimiche (CTC), Università della Calabria, 87036 Cosenza, Italy
| | - Julia Vallejo
- Departament de Química
Inorgànica/Instituto de Ciencia Molecular (ICMol), Universitat de València, 46980 Paterna, València, Spain
| | - Nadia Marino
- Dipartimento di
Chimica e Tecnologie Chimiche (CTC), Università della Calabria, 87036 Cosenza, Italy
| | - Giovanni De Munno
- Dipartimento di
Chimica e Tecnologie Chimiche (CTC), Università della Calabria, 87036 Cosenza, Italy
| | - J. Krzystek
- National
High Magnetic Field Laboratory (NHMFL), Florida State University, Tallahassee, Florida 32310, United States
| | - Joan Cano
- Departament de Química
Inorgànica/Instituto de Ciencia Molecular (ICMol), Universitat de València, 46980 Paterna, València, Spain
| | - Emilio Pardo
- Departament de Química
Inorgànica/Instituto de Ciencia Molecular (ICMol), Universitat de València, 46980 Paterna, València, Spain
| | - Donatella Armentano
- Dipartimento di
Chimica e Tecnologie Chimiche (CTC), Università della Calabria, 87036 Cosenza, Italy
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32
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Akintola O, Hornig D, Buchholz A, Görls H, Plass W. Solvent-dependent selective cation exchange in anionic frameworks based on cobalt(ii) and triphenylamine linkers: reactor-dependent synthesis and sorption properties. Dalton Trans 2017; 46:8037-8050. [DOI: 10.1039/c7dt01405h] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Two anionic cobalt(ii) MOFs were obtained dependent on the reactor design and show a solvent-dependent cation exchange leading to a remarkable increase in the surface area of post-synthetic modified materials.
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Affiliation(s)
- Oluseun Akintola
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität
- 07743 Jena
- Germany
| | - David Hornig
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität
- 07743 Jena
- Germany
| | - Axel Buchholz
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität
- 07743 Jena
- Germany
| | - Helmar Görls
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität
- 07743 Jena
- Germany
| | - Winfried Plass
- Institut für Anorganische und Analytische Chemie
- Friedrich-Schiller-Universität
- 07743 Jena
- Germany
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33
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Akintola O, Ziegenbalg S, Buchholz A, Görls H, Plass W. A robust anionic pillared-layer framework with triphenylamine-based linkers: ion exchange and counterion-dependent sorption properties. CrystEngComm 2017. [DOI: 10.1039/c7ce00369b] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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34
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Woods TJ, Ballesteros-Rivas MF, Gómez-Coca S, Ruiz E, Dunbar KR. Relaxation Dynamics of Identical Trigonal Bipyramidal Cobalt Molecules with Different Local Symmetries and Packing Arrangements: Magnetostructural Correlations and ab inito Calculations. J Am Chem Soc 2016; 138:16407-16416. [DOI: 10.1021/jacs.6b10154] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Toby J. Woods
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | | | - Silvia Gómez-Coca
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Eliseo Ruiz
- Departament
de Química Inorgànica i Orgànica and Institut
de Recerca en Química Teòrica i Computacional, Universitat de Barcelona, Barcelona 08028, Spain
| | - Kim R. Dunbar
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
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35
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Chen L, Cui HH, Stavretis SE, Hunter SC, Zhang YQ, Chen XT, Sun YC, Wang Z, Song Y, Podlesnyak AA, Ouyang ZW, Xue ZL. Slow Magnetic Relaxations in Cobalt(II) Tetranitrate Complexes. Studies of Magnetic Anisotropy by Inelastic Neutron Scattering and High-Frequency and High-Field EPR Spectroscopy. Inorg Chem 2016; 55:12603-12617. [PMID: 27989182 DOI: 10.1021/acs.inorgchem.6b01544] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Three mononuclear cobalt(II) tetranitrate complexes (A)2[Co(NO3)4] with different countercations, Ph4P+ (1), MePh3P+ (2), and Ph4As+ (3), have been synthesized and studied by X-ray single-crystal diffraction, magnetic measurements, inelastic neutron scattering (INS), high-frequency and high-field EPR (HF-EPR) spectroscopy, and theoretical calculations. The X-ray diffraction studies reveal that the structure of the tetranitrate cobalt anion varies with the countercation. 1 and 2 exhibit highly irregular seven-coordinate geometries, while the central Co(II) ion of 3 is in a distorted-dodecahedral configuration. The sole magnetic transition observed in the INS spectroscopy of 1-3 corresponds to the zero-field splitting (2(D2 + 3E2)1/2) from 22.5(2) cm-1 in 1 to 26.6(3) cm-1 in 2 and 11.1(5) cm-1 in 3. The positive sign of the D value, and hence the easy-plane magnetic anisotropy, was demonstrated for 1 by INS studies under magnetic fields and HF-EPR spectroscopy. The combined analyses of INS and HF-EPR data yield the D values as +10.90(3), +12.74(3), and +4.50(3) cm-1 for 1-3, respectively. Frequency- and temperature-dependent alternating-current magnetic susceptibility measurements reveal the slow magnetization relaxation in 1 and 2 at an applied dc field of 600 Oe, which is a characteristic of field-induced single-molecule magnets (SMMs). The electronic structures and the origin of magnetic anisotropy of 1-3 were revealed by calculations at the CASPT2/NEVPT2 level.
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Affiliation(s)
- Lei Chen
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University , Nanjing 210023, People's Republic of China
| | - Hui-Hui Cui
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University , Nanjing 210023, People's Republic of China
| | - Shelby E Stavretis
- Department of Chemistry, University of Tennessee , Knoxville, Tennessee 37996, United States
| | - Seth C Hunter
- Department of Chemistry, University of Tennessee , Knoxville, Tennessee 37996, United States
| | - Yi-Quan Zhang
- Jiangsu Key Laboratory for NSLSCS, School of Physical Science and Technology, Nanjing Normal University , Nanjing 210023, People's Republic of China
| | - Xue-Tai Chen
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University , Nanjing 210023, People's Republic of China
| | - Yi-Chen Sun
- Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology , Wuhan 430074, People's Republic of China
| | - Zhenxing Wang
- Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology , Wuhan 430074, People's Republic of China
| | - You Song
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University , Nanjing 210023, People's Republic of China
| | - Andrey A Podlesnyak
- Quantum Condensed Matter Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Zhong-Wen Ouyang
- Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology , Wuhan 430074, People's Republic of China
| | - Zi-Ling Xue
- Department of Chemistry, University of Tennessee , Knoxville, Tennessee 37996, United States
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36
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Alipour M, Akintola O, Buchholz A, Mirzaei M, Eshtiagh-Hosseini H, Görls H, Plass W. Size-Dependent Self-Assembly of Lanthanide-Based Coordination Frameworks with Phenanthroline-2,9-dicarboxylic Acid as a Preorganized Ligand in Hybrid Materials. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600936] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Mahboubeh Alipour
- Department of Chemistry; Ferdowsi University of Mashhad; 917751436 Mashhad Iran
- Institute für Anorganische und Analytische Chemie; Friedrich-Schiller Universität Jena; Humboldtstraße 8 07743 Jena Germany
| | - Oluseun Akintola
- Institute für Anorganische und Analytische Chemie; Friedrich-Schiller Universität Jena; Humboldtstraße 8 07743 Jena Germany
| | - Axel Buchholz
- Institute für Anorganische und Analytische Chemie; Friedrich-Schiller Universität Jena; Humboldtstraße 8 07743 Jena Germany
| | - Masoud Mirzaei
- Department of Chemistry; Ferdowsi University of Mashhad; 917751436 Mashhad Iran
| | | | - Helmar Görls
- Institute für Anorganische und Analytische Chemie; Friedrich-Schiller Universität Jena; Humboldtstraße 8 07743 Jena Germany
| | - Winfried Plass
- Institute für Anorganische und Analytische Chemie; Friedrich-Schiller Universität Jena; Humboldtstraße 8 07743 Jena Germany
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37
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Villa-Pérez C, Oyarzabal I, Echeverría GA, Valencia-Uribe GC, Seco JM, Soria DB. Single-Ion Magnets Based on Mononuclear Cobalt(II) Complexes with Sulfadiazine. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600777] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Cristian Villa-Pérez
- CEQUINOR; CONICET; CCT La Plata; Departamento de Química; Facultad de Ciencias Exactas; Universidad Nacional de la Plata; 47 y 115 1900 La Plata Argentina
| | - Itziar Oyarzabal
- Departamento de Química Aplicada Facultad de Química; UPV/EHU; Paseo Manuel de Lardizábal 3 20018 Donostia-San Sebastián Spain
| | - Gustavo A. Echeverría
- IFLP; CONICET; CCT La Plata; Departamento de Física; Facultad de Ciencias Exactas; Universidad Nacional de La Plata; 1900 La Plata Argentina
| | - Gloria C. Valencia-Uribe
- GIAFOT; Departamento de Química; Facultad de Ciencias; Universidad Nacional de Colombia-Sede Medellín; Calle 59 A No 63-020 Medellín Colombia
| | - José M. Seco
- Departamento de Química Aplicada Facultad de Química; UPV/EHU; Paseo Manuel de Lardizábal 3 20018 Donostia-San Sebastián Spain
| | - Delia B. Soria
- CEQUINOR; CONICET; CCT La Plata; Departamento de Química; Facultad de Ciencias Exactas; Universidad Nacional de la Plata; 47 y 115 1900 La Plata Argentina
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38
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Roy S, Oyarzabal I, Vallejo J, Cano J, Colacio E, Bauza A, Frontera A, Kirillov AM, Drew MGB, Das S. Two Polymorphic Forms of a Six-Coordinate Mononuclear Cobalt(II) Complex with Easy-Plane Anisotropy: Structural Features, Theoretical Calculations, and Field-Induced Slow Relaxation of the Magnetization. Inorg Chem 2016; 55:8502-13. [DOI: 10.1021/acs.inorgchem.6b01087] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Subhadip Roy
- Department
of Chemistry, National Institute of Technology Agartala, Pin 799046, Tripura, India
| | - Itziar Oyarzabal
- Departamento
de Química Aplicada, Facultad de Química, Universidad del País Vasco, UPV/EHU, Paseo Manuel Lardizabal, No. 3, 20018 Donostia-San Sebastián, Spain
| | - Julia Vallejo
- Institut
de Ciència Molecular, Universitat de València, 46980 Paterna, Valencia, Spain
| | - Joan Cano
- Institut
de Ciència Molecular, Universitat de València, 46980 Paterna, Valencia, Spain
- Fundació General de la Universitat de València, Valencia, Spain
| | - Enrique Colacio
- Departamento
de Química Inorgánica, Facultad de Ciencias, Universidad de Granada, Avenida de Fuentenueva s/n, 18071 Granada, Spain
| | - Antonio Bauza
- Departament
de Quimica, Universitat de les Illes Balears, Crta. de Valldemossa km 7.5, 07122 Palma de Mallorca (Baleares), Spain
| | - Antonio Frontera
- Departament
de Quimica, Universitat de les Illes Balears, Crta. de Valldemossa km 7.5, 07122 Palma de Mallorca (Baleares), Spain
| | - Alexander M. Kirillov
- Centro
de Química Estrutural, Complexo I, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - Michael G. B. Drew
- School
of Chemistry, The University of Reading, P.O. Box 224, Whiteknights, Reading RG66AD, U.K
| | - Subrata Das
- Department
of Chemistry, National Institute of Technology Patna, Ashok Rajpath, Patna 800005, Bihar, India
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39
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Zhang YZ, Gómez-Coca S, Brown AJ, Saber MR, Zhang X, Dunbar KR. Trigonal antiprismatic Co(ii) single molecule magnets with large uniaxial anisotropies: importance of Raman and tunneling mechanisms. Chem Sci 2016; 7:6519-6527. [PMID: 27928492 PMCID: PMC5125373 DOI: 10.1039/c6sc02035f] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 06/15/2016] [Indexed: 11/21/2022] Open
Abstract
A trigonal antiprismatic Co(ii) molecule exhibits counterion-dependent relaxation of the magnetization due to the importance of the Raman relaxation process.
The air-stable mononuclear Co(ii) compounds [CoII(Tpm)2][ClO4]2 (1, Tpm = tris(pyrazol-1-yl)methane), [CoII(Tpm)2][BPh4]2·2MeCN (2) with trigonal antiprismatic geometry (trigonally elongated octahedral geometry) are reported. Magnetic and theoretical studies reveal that the complexes exhibit single-molecule magnet behavior with uniaxial anisotropy and a huge energy difference between ground and first excited Karmers' doublets (∼200 cm–1). Under applied DC fields, compounds 1 and 2 exhibit frequency and temperature dependence of the imaginary susceptibility. The fit of the data to an Orbach relaxation process yields effective energy barriers of 30.6(1) and 44.7(6) cm–1 for 1 and 2, respectively, but there is no real state at that energy. The inclusion of tunneling, direct and Raman relaxation processes leads to the conclusion that the inclusion of an Orbach process is not required to provide a good fit to the data. More interestingly, a detailed study of the dependence of the relaxation time with field shows that for these Kramers' ions, tunneling is the predominant process at low temperature and that differences in the counteranion allow for a tuning of the Raman process at higher temperatures. These findings underscore the fact that large uniaxial anisotropy can be achieved in hexacoordinate Co(ii) trigonal antiprismatic complexes which is an unexplored geometry in mononuclear single molecule magnets.
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Affiliation(s)
- Yuan-Zhu Zhang
- Department of Chemistry , Texas A & M University , College Station , TX 77842-3012 , USA . ; ; Department of Chemistry , South University of Science and Technology of China , 518055 , Shenzhen , P. R. China
| | - Silvia Gómez-Coca
- Department of Chemistry , Texas A & M University , College Station , TX 77842-3012 , USA . ;
| | - Andrew J Brown
- Department of Chemistry , Texas A & M University , College Station , TX 77842-3012 , USA . ;
| | - Mohamed R Saber
- Department of Chemistry , Texas A & M University , College Station , TX 77842-3012 , USA . ; ; Department of Chemistry , Fayoum University , Fayoum 63514 , Egypt
| | - Xuan Zhang
- Department of Chemistry , Texas A & M University , College Station , TX 77842-3012 , USA . ;
| | - Kim R Dunbar
- Department of Chemistry , Texas A & M University , College Station , TX 77842-3012 , USA . ;
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Frost JM, Harriman KLM, Murugesu M. The rise of 3-d single-ion magnets in molecular magnetism: towards materials from molecules? Chem Sci 2016; 7:2470-2491. [PMID: 28660017 PMCID: PMC5477015 DOI: 10.1039/c5sc03224e] [Citation(s) in RCA: 421] [Impact Index Per Article: 52.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 12/22/2015] [Indexed: 12/22/2022] Open
Abstract
Single-molecule magnets (SMMs) that contain one spin centre (so-called single-ion magnets) theoretically represent the smallest possible unit for spin-based electronic devices. The realisation of this and related technologies, depends on first being able to design systems with sufficiently large energy barriers to magnetisation reversal, Ueff, and secondly, on being able to organise these molecules into addressable arrays. In recent years, significant progress has been made towards the former goal - principally as a result of efforts which have been directed towards studying complexes based on highly anisotropic lanthanide ions, such as Tb(iii) and Dy(iii). Since 2013 however, and the remarkable report by Long and co-workers of a linear Fe(i) system exhibiting Ueff = 325 K, single-ion systems of transition metals have undergone something of a renaissance in the literature. Not only do they have important lessons to teach us about anisotropy and relaxation dynamics in the quest to enhance Ueff, the ability to create strongly coupled spin systems potentially offers access to a whole of host of 1, 2 and 3-dimensional materials with interesting structural and physical properties. This perspective summarises recent progress in this rapidly expanding sub-genre of molecular magnetism from the viewpoint of the synthetic chemist, with a particular focus on the lessons that have so far been learned from single-ion magnets of the d-block, and, the future research directions which we feel are likely to emerge in the coming years.
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Affiliation(s)
- Jamie M Frost
- Department of Chemistry and Biomolecular Sciences , University of Ottawa , Ontario , Canada K1N 6N5 . ; ; Tel: +1 613-562-5800 ext. 2733
| | - Katie L M Harriman
- Department of Chemistry and Biomolecular Sciences , University of Ottawa , Ontario , Canada K1N 6N5 . ; ; Tel: +1 613-562-5800 ext. 2733
| | - Muralee Murugesu
- Department of Chemistry and Biomolecular Sciences , University of Ottawa , Ontario , Canada K1N 6N5 . ; ; Tel: +1 613-562-5800 ext. 2733
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Ziegenbalg S, Hornig D, Görls H, Plass W. Cobalt(II)-Based Single-Ion Magnets with Distorted Pseudotetrahedral [N2O2] Coordination: Experimental and Theoretical Investigations. Inorg Chem 2016; 55:4047-58. [DOI: 10.1021/acs.inorgchem.6b00373] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sven Ziegenbalg
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstrasse 8, 07743 Jena, Germany
| | - David Hornig
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstrasse 8, 07743 Jena, Germany
| | - Helmar Görls
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstrasse 8, 07743 Jena, Germany
| | - Winfried Plass
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstrasse 8, 07743 Jena, Germany
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Rechkemmer Y, Breitgoff FD, van der Meer M, Atanasov M, Hakl M, Orlita M, Neugebauer P, Neese F, Sarkar B, van Slageren J. A four-coordinate cobalt(II) single-ion magnet with coercivity and a very high energy barrier. Nat Commun 2016; 7:10467. [PMID: 26883902 PMCID: PMC4757785 DOI: 10.1038/ncomms10467] [Citation(s) in RCA: 309] [Impact Index Per Article: 38.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 12/11/2015] [Indexed: 12/23/2022] Open
Abstract
Single-molecule magnets display magnetic bistability of molecular origin, which may one day be exploited in magnetic data storage devices. Recently it was realised that increasing the magnetic moment of polynuclear molecules does not automatically lead to a substantial increase in magnetic bistability. Attention has thus increasingly focussed on ions with large magnetic anisotropies, especially lanthanides. In spite of large effective energy barriers towards relaxation of the magnetic moment, this has so far not led to a big increase in magnetic bistability. Here we present a comprehensive study of a mononuclear, tetrahedrally coordinated cobalt(II) single-molecule magnet, which has a very high effective energy barrier and displays pronounced magnetic bistability. The combined experimental-theoretical approach enables an in-depth understanding of the origin of these favourable properties, which are shown to arise from a strong ligand field in combination with axial distortion. Our findings allow formulation of clear design principles for improved materials. Bistable single-molecule magnets potentially allow information storage at extremely high densities. Here, the authors study an air- and moisture-stable mononuclear tetrahedral cobalt(II) complex, elucidating the origin of its pronounced magnetic bistability.
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Affiliation(s)
- Yvonne Rechkemmer
- Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, Stuttgart D-70569, Germany
| | - Frauke D Breitgoff
- Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, Stuttgart D-70569, Germany
| | - Margarethe van der Meer
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, Berlin D-14195, Germany
| | - Mihail Atanasov
- Max Planck Institute for Chemical Energy Conversion, Stiftstraße 34-36, Mülheim an der Ruhr D-45470, Germany.,Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria
| | - Michael Hakl
- Laboratoire national des champs magnétiques intenses, CNRS-UJF-UPS-INS, Grenoble F-38042, France
| | - Milan Orlita
- Laboratoire national des champs magnétiques intenses, CNRS-UJF-UPS-INS, Grenoble F-38042, France.,Institute of Physics, Charles University in Prague, Prague CZ-12116, Czech Republic
| | - Petr Neugebauer
- Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, Stuttgart D-70569, Germany
| | - Frank Neese
- Max Planck Institute for Chemical Energy Conversion, Stiftstraße 34-36, Mülheim an der Ruhr D-45470, Germany
| | - Biprajit Sarkar
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, Berlin D-14195, Germany
| | - Joris van Slageren
- Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, Stuttgart D-70569, Germany
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Świtlicka-Olszewska A, Palion-Gazda J, Klemens T, Machura B, Vallejo J, Cano J, Lloret F, Julve M. Single-ion magnet behaviour in mononuclear and two-dimensional dicyanamide-containing cobalt(ii) complexes. Dalton Trans 2016; 45:10181-93. [DOI: 10.1039/c6dt01160h] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The magneto-structural features of one mononuclear and two layered Co(ii) complexes being new examples of Single-Ion Magnets (SIMs) are reported.
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Affiliation(s)
| | - Joanna Palion-Gazda
- Department of Crystallography
- Institute of Chemistry
- University of Silesia
- 40-006 Katowice
- Poland
| | - Tomasz Klemens
- 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
| | - Julia Vallejo
- Department of Química Inorgànica/Instituto de Ciencia Molecular (ICMol)
- Facultat de Quimica de la Universitat de València
- València
- Spain
| | - Joan Cano
- Department of Química Inorgànica/Instituto de Ciencia Molecular (ICMol)
- Facultat de Quimica de la Universitat de València
- València
- 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
- València
- Spain
| | - Miguel Julve
- Department of Química Inorgànica/Instituto de Ciencia Molecular (ICMol)
- Facultat de Quimica de la Universitat de València
- València
- Spain
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Banik R, Roy S, Dlháň Ľ, Titiš J, Boča R, Kirillov AM, Martin AD, Bauza A, Frontera A, Rodríguez-Diéguez A, Salas JM, Das S. Self-assembly synthesis, structure, topology, and magnetic properties of a mononuclear Fe(iii)-violurate derivative: a combined experimental and theoretical study. Dalton Trans 2016; 45:16166-16172. [DOI: 10.1039/c6dt03139k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
New Fe(iii) complex features remarkable supramolecular assembly, antiferromagnetic exchange coupling, and ordering temperature.
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Abstract
One of the determining factors in whether single-molecule magnets (SMMs) may be used as the smallest component of data storage, is the size of the barrier to reversal of the magnetisation, Ueff. This physical quantity depends on the magnitude of the magnetic anisotropy of a complex and the size of its spin ground state. In recent years, there has been a growing focus on maximising the anisotropy generated for a single 3d transition metal (TM) ion, by an appropriate ligand field, as a means of achieving higher barriers. Because the magnetic properties of these compounds arise from a single ion in a ligand field, they are often referred to as single-ion magnets (SIMs). Here, the synthetic chemist has a significant role to play, both in the design of ligands to enforce propitious splitting of the 3d orbitals and in the judicious choice of TM ion. Since the publication of the first 3d-based SIM, which was based on Fe(ii), many other contributions have been made to this field, using different first row TM ions, and exploring varied coordination environments for the paramagnetic ions.
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Affiliation(s)
- Gavin A Craig
- WestCHEM, School of Chemistry, University of Glasgow, Glasgow, G12 8QQ, UK.
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Carl E, Demeshko S, Meyer F, Stalke D. Triimidosulfonates as Acute Bite-Angle Chelates: Slow Relaxation of the Magnetization in Zero Field and Hysteresis Loop of a CoIIComplex. Chemistry 2015; 21:10109-15. [DOI: 10.1002/chem.201406083] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Indexed: 11/07/2022]
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Saber MR, Dunbar KR. Ligands effects on the magnetic anisotropy of tetrahedral cobalt complexes. Chem Commun (Camb) 2015; 50:12266-9. [PMID: 25183324 DOI: 10.1039/c4cc05724d] [Citation(s) in RCA: 160] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The effect of ligands with heavy donor atoms on the magnetic anisotropy of the pseudo-tetrahedral cobalt complexes, Co(quinoline)2I2 (1) and Co(EPh3)2I2 (2-3) (E = P, As) has been investigated. The axial zero-field splitting parameter D was found to vary from +9.2 cm(-1) in 1 to -36.9 cm(-1) in 2 and -74.7 cm(-1) in 3. Compounds 2 and 3 exhibit slow relaxation of the magnetization up to 4 K under an applied dc field, indicating SMM behavior.
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Affiliation(s)
- Mohamed R Saber
- Department of Chemistry, Texas A&M University, College Station, TX 77842-3012, USA.
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Gómez-Coca S, Aravena D, Morales R, Ruiz E. Large magnetic anisotropy in mononuclear metal complexes. Coord Chem Rev 2015. [DOI: 10.1016/j.ccr.2015.01.021] [Citation(s) in RCA: 241] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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