CALCULATED BULK AND SURFACE-PROPERTIES OF SULFATES

Atomistic simulation techniques are used to model a range of sulfates. Two widely different sets of potentials have been developed. The firs t is based on shell model, electron-gas potentials; the second is a ri gid ion model which treats inter- and intra-molecular forces different ly. The success of the potential models has been demonstrated by compa ring calculated and experimental lattice parameters and elastic consta nts. The structures and energetics of surfaces of barite (BaSO4) are e xamined in detail, allowing for the effects of surface relaxation. The two lowest-energy surfaces are {001} and {210} which dominate the cal culated equilibrium morphology.