Structural features of Co-Si, Co-Ge, and Co-Sn binary melts

Abstract

A comparative analysis of the local structures of binary Co— IVA Group element (Si, Ge, Sn) melts is performed using partial structural characteristics, which were calculated by three-dimensional mod els reconstructed from experimental structure factor curves by reverse Monte Carlo method. These melts are characterized by a common feature that consists in the existence of a marked interaction between atoms of different kinds, which are located at distances close to those in the corresponding intermetallics. Zigzag chains formed by covalently bound silicon and germanium atoms are found to exist in Co— Si and Co— Ge melts. This is due to the thermal dissociation of the intermetallics during melting and partial retention of the covalent bond between germanium atoms in higher germanides. In passing from Co— Si to Co— Ge and Co— Sn melts, a marked increase in the interaction between cobalt atoms takes place along with a decrease in the interaction between second-component atoms; in particular, this is especially typical of Co— Sn melts.