THEORETICAL AND EXPERIMENTAL ELECTRON DENSITY ANALYSES OF DIHYDROXYBENZOPHENONE. F. K. Ross, Z. Hu, and R. Glaser, Research Reactor Center and Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211, USA

Detailed electron density distributions for dihydroxybenzophenone (DHBP, C1₃H₁₀O) have been obtained from X-ray+Neutron (X+N) diffraction analysis and by ab initio molecular orbital calculations(1) for a closely analogous structure. Various mechanisms for accounting for H atom bond polarization in the X+N model are tested and compared with results from theory. Anharmonic thermal motion appears to be a significant effect and must be adequately modeled before good agreement of the two methods is achieved. Comparisons of charge density distributions, orbital population parameters, potential maps and critical points will be discussed.

(1) R. Dovesi, V.R. Saunders and C. Roetti, CRYSTAL92, An ab-initio Hartree-Fock LCAO program for periodic systems, University of Turin and SERC, Daresbury (UK).