Conformational polymorphs of 1,1,2,2-tetrachloroethane: pressure vs. temperature

Abstract

Directional Cl⋯Cl type I and II interactions govern the low-density aggregation of 1,1,2,2-tetrachloroethane molecules in synclinal conformation in the crystalline state at low temperature, whereas the dense molecular packing in high-pressure is achieved for the antiperiplanar conformers and electrostatically less favored Cl⋯Cl contacts. The mechanism of transformation between loose and dense associations involves the collapse of Cl⋯Cl contacts and conformational conversion.