A new determination method of interatomic potential for sodium silicate glass simulations

An interatomic potential for the classical molecular dynamics (MD) simulation of sodium silicate glasses was proposed. The ionic charges for this interatomic potential were determined by Mulliken population analysis via the density functional theory (DFT) calculation of alkali silicate crystals. The Si O interatomic potential energy curve was determined by molecular orbital (MO) calculation of SiO ^{2 +} . The results of classical MD simulations using the new interatomic potential were consistent with the experimental trends in interatomic distance, thermal expansion coefficient, molar volume, Si O Si bond angle distribution, and Q _n ratio with respect to the sodium composition of the silicate glass. The proposed interatomic potential improves the reproducibility of the ring size distribution in silicate glasses compared to conventional potentials.