Surface tension and self-diffusion coefficient of liquid Si and Ge

Abstract Temperature-dependent surface tension γ lv ( T ) and its temperature coefficient γ ′ lv ( T )=d γ lv ( T )/d T for liquid silicon and germanium ( l -Si and l -Ge) are thermodynamically modeled based on an established model for surface energy of crystals. Combining the relationship among γ lv ( T ), self-diffusion coefficient D and liquid viscosity η , temperature dependent D ( T ) function is also modeled. The model predictions correspond to the available experimental results. It is found that γ lv ( T )∝ T , γ ′ lv ( T )∝ T and D ( T )∝ T 3/2 at a certain temperature range (including T T m and T ⩾ T m where T m is the melting temperature).