COMPUTATIONAL STUDIES OF CRYSTALLINE H3PO4

A polarized split-valence wavefunction was computed for the H3PO4 mole cule at its neutron crystallographic valence geometry, and the wavefun ction was used to map the molecular electron-density distribution and to simulate X-ray crystal structure factors for both static, at-rest a nd dynamic thermally averaged structures. The thermal vibrational aver aging was approximated using anisotropic mean-square atomic displaceme nts from similar to 300K neutron diffraction data. The simulated X-ray data were used to test pseudoatom multipole modeling of the valence e lectron-density distribution, in particular, radial modeling of the M valence shell of the P atom, and deconvolution of the nonspherical den sity features from anisotropic vibrational smearing.