화학공학소재연구정보센터
Turkish Journal of Chemistry, Vol.30, No.1, 77-87, 2006
Chromium(III) complexes with different chromospheres macrocyclic ligands: Synthesis and spectroscopic studies
Symmetric tetradentate (L-1) and asymmetric pentadentate (L-2) macrocyclic ligands that possess 2 dissimilar coordination sites were prepared. One has a 4-coordinate (N-4) and the other has a 5-coordinate (N2O3S) donor set. Trivalent Cr(III) complexes were synthesized with L-1 and L-2 and their structures were investigated using elemental analyses and magnetic moment, electronic, IR, H-1 NMR, C-13 NMR and EPR spectra. All the Cr(III) complexes show magnetic moments corresponding to a high-spin configuration. Delta values indicate the energy difference between the principle bands, which are formed due to ligand field absorption. The spin-orbit coupling parameter, z, gives no significance because the splitting of doublet transition lines is too large to be explained by spin-orbit coupling. lambda values indicate that the complexes under study have a substantial covalent character. g-values were also calculated using the spin-orbital coupling constant, lambda.