The full potential linear muffin-tin orbital (FP-LMTO) method was applied to study the structural and electronic properties of the compounds MgO, ZnO and their alloy Mg x Zn 1-x O in the zincblende and NaCl structures. Results are obtained using the local density approximation (LDA), the ground-state properties like lattice constant and bulk modulus obtained agree very well with experimental and other theoretical calculations. The effect of composition on lattice constant from Vegard's law and the bulk modulus was investigated. The microscopic origins of the gap bowing were explained by using the approach of Zunger and co-workers. It is concluded that the energy band gap bowing is primarily due to chemical charge-transfer effect. Contribution of volume deformation and structural relaxation to the gap bowing parameter is found to be very small.

The present work performs self-consistent <i>ab</i> <i>initio</i> full-potential linear muffin-tin orbital (FP-LMTO) method to study the structural and electronic properties of the ternary Zn_xCd₁_-_xSe alloy, based on density functional theory (DFT). In this approach, both the local density approximation (LDA) and the generalized gradient approximation (GGA) were used for the exchange-correlation potential calculation. The ground-state properties are determined for the bulk materials CdSe, ZnSe and their alloy in cubic phase. In particular, the lattice constant, bulk modulus, electronic band structures and effective mass. We mainly showed deviation of the lattice parameter and bulk modulus from Vegard’s law of our alloys. We also presented the microscopic origins of the gap bowing using the approach of Zunger <i>et al</i>. The results are compared with other theoretical calculations and experimental data and are in reasonable agreement