Hydrogen bonding and C-H.O interactions in 2-

The title acid, C(19)H(16)O(2), crystallized in the centrosymmetric space group Pnna with three molecules in the asymmetric unit (apparently the first reported instance of Z' = 3 in this space group). Four intermolecular hydrogen bonds have O(D).O(A) distances of 2.660 (2), 2.594 (2), 2.633 (2) and 2.646 (2) A, and angles of 177 (2), 179 (2), 175 (2) and 175 (2) degrees. The four hydrogen bonds form two R(2)(2)(8) cyclic dimers, one about a twofold axis. Five leading intermolecular C-H.O interactions are present. Although first- and second-level graph sets involving these nine interactions are dominated by finite patterns, a three-dimensional network becomes evident upon analysis of higher-level graphs. A number of intramolecular C-H.O interactions are also present.