Pressure induced structural phase transition in MgS and CaS

Pressure-induced structural phase transition and phase stabilities of MgS and CaS are investigated by using a three-body potential approach The calculated compression curves of MgS and CaS have been compared with the available experimental data. The accuracy of the model in reproducing the equations of state of both compounds is generally comparable to the experimentally measured values. We also discuss the phase stability of both MgS and CaS. Our calculations accurately determine the B1-B2 phase transition for CaS at 39 GPa, which is similar to other investigations and measurements. We predict the B1-B2 phase transition for MgS at 158 Gpa, which could not be compared with experimental data as it is not available. (C) 1998 Elsevier Science Ltd. All rights reserved.