Vibrational Spectra and Normal Coordinate Analysis for an Imidazole Bridged Copper, Zinc Binuclear Complex

Abstract The normal coordinate analysis of a model compound for Cu, Zn-SOD: [(dtma)CuImZn(dtma)]CIO4 · 2.5H2O (where dtma = 4-diethylenetriamineacctate; Im = imidazolate) has been carried out by using a Urey-Bradley force field. According to the molecular structure, 240 internal coordinates were established and 174 theoretical vibrational frequencies were calculated. Due to introducing an appropriate set of internal coordinates and force constants in the course of calculation, the calculated frequencies agree well with the observed values, with the average difference 4.40cm−1 and the maximum deviation 24.2cm−1 between them, although the structure of the title compound is complicated. Some structural and spectral properties are here discussed.