Buy article online - an online subscription or single-article purchase is required to access this article.
organic compounds
The title acid, C18H12O3, crystallizes in the centrosymmetric space group C2/c and exhibits carboxyl group hydrogen bonding of the cyclic dimer type about a center of symmetry. The Odonor-Oacceptor distance in the hydrogen bond is 2.692 (2) Å. In addition, seven C—H groups and the three O atoms in the molecule are involved in significantly attractive C—HO interactions with 11 neighbors, forming a three-dimensional network. The carboxylic H atom is ordered, as are the carboxylic O atoms.