Structural flexibility in octahedral tin(IV) bischelates: electronic and hybridization effects

PM3 calculations on the his chelates containing acetylacetonato and dithioc arbamato groups with two monodentate ligands reveal the existence of cis an d skew trapezoidal bipyramid(STB) octahedral geometry for these complexes. The calculations also show that the nitrate complexes assume bicapped tetra hedral geometry. Crystallographic investigation on the complex, Br2Sn[S2CN( C2H5)(2)](2) confirms the cis orientation of the bromine atoms, as predicte d by the calculations.