Crystal structure and Hirshfeld surface analysis of a new polymorph of (E)-2-(4-bromophenyl)-1-[2,2-dibromo-1-(3-nitrophenyl)ethenyl]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 molecules into chains. These chains are linked by face-to-face π–π stacking interactions, resulting in a layered structure. Short inter-molecular Br...O contacts and van der Waals interactions between the layers aid in the cohesion of the crystal packing. In the previously reported form-1, C—H...Br interactions connect molecules into zigzag chains, which are linked by C—Br...π interactions into layers, whereas the van der Waals interactions between the layers stabilize the crystal packing of form-2. Hirshfeld molecular surface analysis was used to compare the intermolecular interactions of the polymorphs.

Keywords

• crystal structure
• azo compounds
• polymorphism
• c—h...o interactions
• hirshfeld surface analysis