3D energy frameworks of dimethylbenzophenone tetramorphs

Abstract

The tetramorphth crystals of 4,4–dimethylbenzophenone (D) were obtained using slow-evaporation crystallization method and the structure is elucidated using single crystal X-ray diffraction technique. D crystallizes in the orthorhombic crystal system (space group Pbca) with cell parameters a = 14.6986 (11) Å, b = 6.1323 (4) Å, c = 26.2730 (18) Å, V = 2368.2 (3) Å3 and Z = 8. In the crystal structure, intermolecular interaction of the type C---H...π stabilizes the crystal packing. This polymorph is the fourth candidate of its kind and second candidate in the orthorhombic crystal system. The structural comparisons and crystal packing of tetramorphs (A, B, C and D) are analyzed using molecular structures, Hirshfeld surfaces, enrichment ratios (E) and energy frameworks. The conformational differences are observed in all the tetramorphs and the intercontacts H⋯H and C⋯H contributes around 85 % to the Hirshfeld surfaces. The E ratio provides evidence of H⋯H, C⋯H and O⋯H intercontacts having high propensity to form contacts in the crystal packing. The average energy (dimer formation) for each polymorph is calculated from energy framework analysis. The systematic comparison of crystal packing in tetramorphs through 3D-topology is visualized. In the energy-frameworks of the crystal packing, dispersion energy dominates over the electrostatic energy. Overall, the molecular packings of the four polymorphic structures are different.