First principles calculations of the ground-state properties and structural phase transformation in CdO

We have studied the structural properties of CdO in the rock-salt (sodium chloride), cinnabar, orthorhombic cmcm, cesium chloride, nickel arsenide, zinc blende, and wurtzite structures using first-principles total energy calculations. Rock-salt is the calculated ground state structure with a=4.77, B₀=130GPa. The experimental lattice constant is a=4.704. There is an additional local minimum in the wurtzite structure. Within the precision of the calculations, its total enrgy is the same as the energy of the rock-salt structure. At high pressure (~89Gpa), our calculations predict a phase transformation from the NaCl to a CsCl structure.