Surface Effects in the Pressure-Induced Structural Transformation of a ZnO Nanorod

We report on molecular dynamics simulations of an atomistic zinc oxide nanorod model embedded in a pressure medium. The transformation of the nanorod from wurtzite to rocksalt structure is investigated using both brute-force over-pressurization and transition path sampling at a much lower pressure. The latter approach yields the underlying mechanisms at more realistic conditions and reveals the interplay of the morphogenesis of the rocksalt-type structure domains with shape deformation of the overall nanorod. Surface effects are observed to not only influence dedicated nucleation sites but also impose control mechanisms to phase growth and to specific shape deformation.