Coordination geometry skew-trapezoidal

Structure of Et2Sn(ACDA)2 (8) The X-ray structure of 8 has been reported by Flores et al. [101] In this complex geometry obtained aroimd tin is a skew trapezoidal bipyramid with both organic residues in mutual trans-positions. The coordination occurs through both sulfur atoms in an asymmetric fashion and there is hydrogen bond between the NH and one of the sulfur atoms of the carbodithioate moiety. Therefore the coordination mode of ligand in 8 is similar to our complexes, so the steric hinderance on tin has little effect over the coordination pattern. 

A large number of bis(dithiocarbamate)tin(I V) complexes of general formula [SnR X2 (S2CNR2)2] (R = alkyl or aryl X = halogen or pseudo-halogen = 0, 1, or 2) have been reported (89, 95, 111-115, 117, 119, 122-167). In the majority of cases, the geometry at tin is best described as a highly distorted octahedron or skew-trapezoidal bipyramid, with asymmetrically coordinated... 

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