Crystal structure of 2-bromo-benzoic acid at 120 K: a redetermination.

Abstract

The crystal structure of the title compound, C7H5BrO2, was originally studied using photographic data at room temperature with Cu Kα radiation [Ferguson & Sim (1962 ▶). Acta Cryst. 15, 346–350]. The present study was undertaken at 120 K with a CCD diffractometer using Cu Kα radiation, and resulted in improved geometrical parameters. In the mol­ecule, the carb­oxy group is inclined to the benzene ring by 18.7 (2)° and there is a close intra­molecular Br⋯O contact of 3.009 (3) Å. In the crystal, mol­ecules are linked by pairs of O—H⋯O hydrogen bonds, forming inversion dimers with the classical R 2 2(8) ring motif for carb­oxy­lic acids. Neighbouring dimers are linked by weak C—H⋯O hydrogen bonds, forming tapes propagating in [1-10]. Adjacent tapes inter­act by slipped parallel π–π inter­actions [inter-centroid distance = 3.991 (2), inter­planar distance = 3.509 (2) Å, slippage = 1.900 Å] to form columns approximately along the b-axis direction. Neighbouring columns inter­act dispersively, forming a three-dimensional framework structure.