Polymorphism in Bis(4-dimethylamino- pyridinium)tetrachlorocuprate(II)

Abstract

The title compound crystallizes in both a yellow and a green phase. The pyridinium cations form bifurcated hydrogen bonds to the CuCl42- anions to form molecular species. The packing of these molecular species force the CuCl42- chromophore to be distorted more toward a square planar geometry in the green phase. The packing in both phases appears to be strongly influenced by C−H···Cl electrostatic interactions.