WEAK HYDROGEN-BONDING .3. A BENZYL GROUP ACCEPTING EQUALLY STRONG HYDROGEN-BONDS FROM O-H AND C-H DONORS - 5-ETHYNYL-5H-DIBENZO[A,D]CYCLOHEPTEN-5-OL

In the crystal structure of the title compound, one of the benzyl grou ps accepts hydrogen bonds from a hydroxy and an ethynyl group, one to each face of the ring. For both hydrogen bonds, energies around -1.3 k cal mol(-1) have been calculated. The bond donated by the hydroxy grou p has unusual geometry and is directed almost linearly at a C atom wit h H...C = 2.36 Angstrom.