Soret effect in binary glass-forming oxide melts: theory and its verification

Abstract

Soret effect is temperature-gradient-driven mass diffusion in a multicomponent system. This paper reviews the recent progress of understanding the Soret effect in glass-forming oxide melts. A new model, called adjusted Kempers model, is proposed to quantitatively predict Soret coefficients in binary glass-forming oxide melts. The model is verified by experiment and molecular dynamics simulation. In a 11Na₂O–89B₂O₃ (mol %) melt, the difference of the Soret coefficient of Na₂O between experiment and theory is 19%. In the nonequilibrium molecular dynamics simulation of CaO–SiO₂ glass melts, the Soret coefficient of SiO₂ is decreased with SiO₂ content and a sign change is observed, which is consistent with the adjusted Kempers model. These results indicate that the adjusted Kempers model is promising. Additionally, this paper reviews the laser-induced Soret effect in multicomponent glasses.