A computational study of liquid-solid interfacial free energy (γ) for SW-Ge potential model

In this work, the melting temperature and liquid-solid interfacial free energy for germanium has been computed by using Stillinger-Weber (SW) potential model. The tetrahedral parameter value of SW potential model was used as 19.5 for numerical simulations. The NVT-MC simulations were performed to compute interfacial free energy with 2235 and 2048 particles for liquid and solid respectively. Initially, the free energy difference between two liquid phase of germanium has been computed by thermodynamic integration method along a reversible path at zero pressure and different temperature values. The melting temperature for SW potential model of germanium is obtained as Tm≈1360K. Further, the cleaving wall method was used to compute the liquid-solid interfacial free energy for high density liquid to low density liquid phase transition with SW-Ge potential model. This liquid-solid interfacial free energy has been computed below the melting temperature or at liquid-liquid transition temperature as Tll=1312K. This computational study has been performed for understanding the phase behavior and crystal growth of SW-Ge potential model at or near the transition temperature. The results shown here are consistent with the experimental and computational literature values of interfacial free energy for germanium.