A MOLECULAR DYNAMICS SIMULATION OF Na2O center dot 2SiO(2) - K2O center dot 2SiO(2) MELTS - EFFECT OF BASIC CELL SIZE

A pseudo-binary alkali disilicate liquid system, Na2O center dot 2SiO(2) - K2O.2SiO(2), was investigated by means of molecular dynamics (MD) simulations. Enthalpy of mixing, diffusion coefficient of component ions, etc. revealed their non-linear mixing properties. The negative deviation of enthalpy of mixing was observed by the present MD calculations as well as by the experimental results. The behaviour of the systems with different number of atoms (450:small and 900:large) in a MD basic cell was investigated, and it was concluded that the small system is insufficient to investigate both static and dynamic properties with the present interatomic potential model.