Thermal and magnetic behaviour of 5-chloro-2-nitrobenzoates of Co(II), Ni(II) and Cu(II)

Abstract

Chloro-2-nitrobenzoates of Co(II), Ni(II) and Cu(II) having formulae Co(C 7 H 3 O 4 NCl) 2 Á3H 2 O, Ni(C 7 H 3 O 4 NCl) 2 Á3H 2 O and Cu(C 7 H 3 O 4 NCl) 2 Á2H 2 O, were obtained as polycrystalline compounds. From the IR spectra analysis of complexes, sodium salt and according to the spectroscopic criteria the carboxylate ions seem bidentate groups. The complexes of Co(II) and Cu(II) lose the water of crystallization in one step at 363-523 K. The Ni(II) complex loses it in two stages in the ranges of 323-378 and 378-523 K, respectively. The compounds follow the Curie-Weiss law. The magnetic moment values experimentally determined change from 4.53 to 4.55 l B for Co(II) complex, from 2.34 to 2.97 l B for Ni(II) 5-chloro-2-nitrobenzoate and from 1.80 to 1.90 l B for Cu(II) complex. Keywords 5-Chloro-2-nitrobenzoates Á Thermal stability Á Magnetic moments Á Co(II) Á Ni(II) Cu(II) complexes

New Type of Single Chain Magnet: Pseudo-One-Dimensional Chain of High-Spin Co(II) Exhibiting Ferromagnetic Intrachain Interactions

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Effect of cobalt(II) complexes with dipyridylamine and salicylaldehydes on cultured tumor and non-tumor cells: Synthesis, crystal structure investigations and biological activity

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Synthesis, spectral and thermal aspect of transition metal coordination polymers with bis-hydrazone ligand

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