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Suppressing of slow magnetic relaxation in tetracoordinate Co(II) field-induced single-molecule magnet in hybrid material with ferromagnetic barium ferrite.

ABSTRACT: The novel field-induced single-molecule magnet based on a tetracoordinate mononuclear heteroleptic Co(II) complex involving two heterocyclic benzimidazole (bzi) and two thiocyanido ligands, [Co(bzi)2(NSC)2], (CoL4), was prepared and thoroughly characterized. The analysis of AC susceptibility data resulted in the spin reversal energy barrier U = 14.7 cm(-1), which is in good agreement with theoretical prediction, U(theor).?= 20.2 cm(-1), based on axial zero-field splitting parameter D =?-10.1 cm(-1) fitted from DC magnetic data. Furthermore, mutual interactions between CoL4 and ferromagnetic barium ferrite BaFe12O19 (BaFeO) in hybrid materials resulted in suppressing of slow relaxation of magnetization in CoL4 for 1:2, 1:1 and 2:1 mass ratios of CoL4 and BaFeO despite the lack of strong magnetic interactions between two magnetic phases.

SUBMITTER: Nemec I

PROVIDER: S-EPMC4454148 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Suppressing of slow magnetic relaxation in tetracoordinate Co(II) field-induced single-molecule magnet in hybrid material with ferromagnetic barium ferrite.

Nemec Ivan I Herchel Radovan R Trávníček Zdeněk Z

Scientific reports 20150603

The novel field-induced single-molecule magnet based on a tetracoordinate mononuclear heteroleptic Co(II) complex involving two heterocyclic benzimidazole (bzi) and two thiocyanido ligands, [Co(bzi)2(NSC)2], (CoL4), was prepared and thoroughly characterized. The analysis of AC susceptibility data resulted in the spin reversal energy barrier U = 14.7 cm(-1), which is in good agreement with theoretical prediction, U(theor). = 20.2 cm(-1), based on axial zero-field splitting parameter D = -10.1 cm( ...[more]

PMID: 26039085

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