6533b81ffe1ef96bd1277d72

RESEARCH PRODUCT

High-pressurein-situcrystallization, structure and phase transitions in 1,2-dichloroethane

Maciej BujakAndrzej KatrusiakArmand Budzianowski

subject

Phase transitionChemistryIntermolecular forceSpace groupCondensed Matter Physicslaw.inventionInorganic ChemistryCrystalCrystallographylawPhase (matter)General Materials ScienceCrystallizationSingle crystalMonoclinic crystal system

description

AbstractThe single crystal of 1,2-dichloroethane, C2H4Cl2wasin-situcrystallized in a Merrill-Bassett diamond-anvil cell, and its structure determined at 0.7 GPa and 280 K. The crystals are monoclinic, space groupP21/c. The C2H4Cl2molecules in thes-transconformation are located at the inversion centers. The —H2C—CH2—ethylene group is disordered in two sites, with equal occupancies, one rotated by 180° to the other about the Cl⋯Cl axis of the molecule. The crystal cohesion forces have been attributed mainly to Cl⋯Cl intermolecular interactions, and their role in the mechanism of the phase transition at 177 K has been analysed. It was found that the order-disorder phase transition in the structure of 1,2-dichloroethane is associated with the breaking of the Cl⋯Cl intermolecular interactions in the disordered phase. The crystal amorphization under non-homogeneous strain and subsequent transition to a new pressure-induced polymorph at 1.5 GPa has been observed.

https://doi.org/10.1524/zkri.219.9.573.44041