Molecular dynamics simulations of solvent effects on the crystal morphology of lithium carbonate.

Abstract

The attachment energy (AE) model was employed to investigate the growth morphology of Li2CO3 under vacuum and water solvent conditions by molecular dynamics simulations. The attachment energy calculation predicted the growth morphology in vacuum dominated by the (1 1 −1), (0 0 2) and (1 1 0) crystal faces. A modified attachment energy model, accounting for the surface chemistry and the corresponding topography of the habit crystal plane, was established to predict the morphological importance of crystal faces in a water solvent. Moreover, radial distribution function (RDF) and diffusion coefficient analyses were performed to explore the adsorption and diffusion behaviors of solvent molecules on the Li2CO3 crystal faces. The calculated results showed that with the solvent effects, the (0 0 2) and (1 1 0) faces were of great morphological importance, while the (1 1 −1) face disappeared gradually. These finally resulted in a cuboid-like Li2CO3 crystal. The growth morphology and the corresponding X-ray powder diffraction pattern derived from the modified AE model were in accordance with the results observed in experiments. The related model provides an important basis for the further investigation of the effects of impurities.