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 molecular ionic solid sodium chlorate is presented. This prediction uses interatomic potential calculations that employ surface-specific attachment energy calculations associated with an ab initio calculation of surface charges via a Hartree-Fock calculation using periodic boundary conditions. The data predicts assignment of the absolute polarity of the crystal with respect to the published crystal structure (Burke-Laing, M. E.; Trueblood, K. N. Acta Crystallogr. 1977, B33, 2698), which reveals the chlorate-rich {-1 -1 -1} to be the observed form rather than its sodium-rich Freidel opposite, {111}. The predicted crystal morphology is in reasonable agreement with observed morphologies, although there is an underestimation of the dominant {200} form. The latter is rationalized with experimental data in terms of a face-specific solvent binding model.