Reversible crystal-to-crystal phase transition in dibromobis(4-vinylpyridine)zinc

Abstract

Abstract In the solid state the mononuclear tetrahedral complex dibromobis(4-vinylpyridine)zinc shows a reversible crystal-to-crystal phase transition which was studied by temperature dependent single crystal X-ray diffraction experiments. At low temperatures the compound crystallizes in space group P1̅ with one ordered complex molecule in general position. Results derived from an intensity data set collected at 120 K are reported. Above the phase transition at 207 K both the cell metric and the symmetry of the diffraction pattern allow the transformation to a centered monoclinic unit cell in space group C2/c. In this high temperature phase the molecule is located on a twofold crystallographic axis and shows disorder with respect to the orientation of the vinyl substituent. The crystal and molecular structure based on a data collection at 293 K is described.