Publication in Dalton Transactions

A tridentate ligand L (2,6-bis(1-(3,5-di-tert-butylbenzyl)-1H-benzimidazol-2-yl)pyridine) was synthesized and used for the preparation of three pentacoordinated Co(II) complexes of formula [Co(L)X2] (where X = NCS for 1, X = Cl for 2 and X = Br for 3) and one ionic compound 4 ([Co(L)2]Br2·2CH3OH·H2O) containing a hexacoordinated Co(II) centre. Static magnetic data were analysed with respect to the spin (1–3) or the Griffith–Figgis (4) Hamiltonian. Ab initio calculations enable us to identify the positive axial magnetic anisotropy parameter D accompanied by a significant degree of rhombicity in the reported complexes. Also, magneto-structural correlation was outlined for this class of compounds. Moreover, all four compounds exhibit slow relaxation of magnetisation at an applied static magnetic field with either both low- and high-frequency relaxation channels (3) or a single high-frequency relaxation process (1, 2 and 4). The interplay between the stereochemistry of coordination polyhedra, magnetic anisotropy and the relaxation processes was investigated and discussed in detail.

Date: 6. feb 2020 | Author: agch

Department of Inorganic Chemistry

Faculty of Science
Palacký University in Olomouc

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CZ-771 46 Olomouc
Czech Republic

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email : agch(at)upol.cz