Cis and Trans Isomers of Fe(II) and Co(II) Complexes with Oxadiazole Derivatives - Structural and Magnetic Properties
Abstract
Four complexes with bidentate N,N-donors 2-(furan-2-yl)-5-(pyridin-2-yl)-1,3,4-oxadiazole (fpo) and 2-(pyridin-2-yl)-5-(thiophen-2-yl)-1,3,4-oxadiazole (pto) with general formula [M(L)(2)(NCS)(2)] (M=Co(II), L=fpo for (1); M=Co(II), L=pto for (2); M=Fe(II), L=fpo (3); M=Fe(II), L=pto (4)) are reported. Analysis and characterization of the samples was performed using standard physico-chemical techniques - elemental analysis, nuclear magnetic resonance, Fourier transform infrared spectroscopy, single-crystal X-ray diffraction.
Magnetic properties for 1-4 revealed large magnetic anisotropy of Co(II) complexes, and AC susceptibility measurements confirmed their single-molecule magnetic behaviour. Furthermore, the theoretical calculations at DFT and CASSCF/NEVPT2 level of theory were exploited to better understand magnetism of these compounds.