Crystal structure and Hirshfeld surface analysis of a new polymorph of (E)-2-(4-bromo-phen-yl)-1-[2,2-di-bromo-1-(3-nitro-phen-yl)ethen-yl]diazene.

Abstract

A new polymorph of the title compound, C14H8Br3N3O2, (form-2) was obtained in the same manner as the previously reported form-1 [Akkurt et al. (2022 ▸). Acta Cryst. E78, 732-736]. The structure of the new polymorph is stabilized by a C-H⋯O hydrogen bond that links mol-ecules into chains. These chains are linked by face-to-face π-π stacking inter-actions, resulting in a layered structure. Short inter-mol-ecular Br⋯O contacts and van der Waals inter-actions between the layers aid in the cohesion of the crystal packing. In the previously reported form-1, C-H⋯Br inter-actions connect mol-ecules into zigzag chains, which are linked by C-Br⋯π inter-actions into layers, whereas the van der Waals inter-actions between the layers stabilize the crystal packing of form-2. Hirshfeld mol-ecular surface analysis was used to compare the inter-molecular inter-actions of the polymorphs.