Condensed Water Phase Nuclei in the Field of a Vacancy on a Crystalline Substrate Surface

Abstract

A vacancy has been formed in a crystal lattice by removing an iodine anion from the crystallographic layer nearest to the surface on the basal face of the β-modification of silver iodide. The Monte Carlo method has been employed to study the molecular structure of condensed water phase nuclei growing in the field of the vacancy from a vapor at 260 K. The images and spatial correlation functions obtained for the nuclei in the region of the surface defect have indicated a relatively deep penetration of water molecules into the first crystallographic layers and the rupture of hydrogen bonds between the first adsorbed molecules. The growth of a nucleus in the vacancy field initially develops in the form of molecular chains extended in the direction outward the crystal surface; then, it continues in the form a monomolecular film spot spreading over the surface around the vacancy, with the mechanism of spot retention being the same as that on a defectless surface. The nuclei in the vacancy field are represented by monomolecular film spots with vertical protuberance-like prominences raised over them.