Simulation of Plasticity of Copper(II) Coordination Polyhedron by Means of an Empirical Force Field Method

The empirical force field method of conformational analysis was used in order to reproduce the distorted planar geometry of bis-eN-alkylsalicylaldiminato) copper(II) complexes. The problem was partly solved by introducing two apically bonded »dummy« atoms. The parameters adjusted to reproduce the configuration of copper atom in the orthorhombic modification of ethylated derivative, were shown to be adequate for the calculation of epimer- -selectivity effect in epimeric (M(L-ligand) (L-ligand) and M(L- -Iigand) (D-ligand)) copper(II) complexes with N,N-dimethylvaline. Calculations on other, more distorted structures of N-substituted copper(II) bis-salicylaldiminates (substituents: ethyl, t-butyl and i-propyl) were not able to reproduce crystal geometries suggesting that the model is applicable only for small deviations from planarity