PREDICTION OF THE POLAR MORPHOLOGY OF SODIUM-CHLORATE USING A SURFACE-SPECIFIC ATTACHMENT ENERGY-MODEL

A morphological prediction of the polar crystal morphology of the mole cular ionic solid sodium chlorate is presented. This prediction uses i nteratomic potential calculations that employ surface-specific attachm ent energy calculations associated with an ab initio calculation of su rface charges via a Hartree-Fock calculation using periodic boundary c onditions. The data predicts assignment of the absolute polarity of th e crystal with respect to the published crystal structure (Burke-Laing , M. E.; Trueblood, K. N. Acta Crystallogr. 1977, B33, 2698), which re veals the chlorate-rich {-1 -1 -1} to be the observed form rather than its sodium-rich Freidel opposite, {111}. The predicted crystal morpho logy is in reasonable agreement with observed morphologies, although t here is an underestimation of the dominant {200} form. The latter is r ationalized with experimental data in terms of a face-specific solvent binding model.