The crystal and molecular structure of N2H5[M(N2H3COO)3] • H2O (M ∈{ Co, Zn}) isomorphic compounds -: an X-ray crystallographic, vibrational spectroscopic and quantum-chemical study

A systematic study of N2H5[M(N2H3COO)(3)](H2O)-H-. (Mis an element of{Co, Zn}) type of compounds, which are typical model systems for transition metal complexes with a-amino acids (the latter are not obtainable in crystalline form), was carried out. The crystal structures of these compounds were solved by X-ray crystallographic methods. FTIR spectra at room and low temperature (similar to100 K) as well as Raman spectra at room temperature were recorded, and analyzed in details. Also, the geometries of the Zn(N2H3COO)(3)(-) and N2H5+ species were fully optimized at ab initio HF and B3LYP/6-31 + G(d,p) level of theory, and subsequent vibrational analyses were performed on the basis of which several important reassignments of the IR and Raman bands were proposed. In order to study the binding energetics and the ligand-cation charge-transfer interactions within the Zn(N2H3COO)(3)(-) complex, NBO analysis was carried out, employing the second-order perturbation theory analysis of the Fock matrix (i.e., its Kohn-Sham analog) within the NBO basis. (C) 2004 Published by Elsevier Inc.