Relaxation of thermal concentration fluctuations in ternary liquids

Abstract Many small-angle neutron experiments have proven that concentration fluctuations develop in liquid alloys. The present work is devoted to the study of the relaxation of these concentration fluctuations. The mathematics associated with the analysis is close to the normal mode treatment of lattice vibrations. When applied to a ternary liquid exhibiting strong heteroatomic bonding between two components having high atomic mobilities, a long-lived clustering mode of relaxation and a short-lived substitutional mode are defined. It is found that the long-lived clustering relaxation mode is generated from a concentration fluctuation which is also the most probable. This gives physical meaning to the socalled ‘clustering’ in liquids where atomic cohesion is governed by metallic bonding. The possible influence of these long-lived clusters on crystalline nucleation is also discussed.