Electronic and structural properties of BaTe

We present the results of a theoretical study of the structural and electronic properties of BaTe, using first principle pseudopotential plane wave (PP-PW) and full potential linear augmented plane wave (FP-LAPW) methods. In both approaches the generalized gradient approximation (GGA) was used for the exchange-correlation potential. In the case of PP-PW we repeated the calculation using local density approximation (LDA). Our calculated values for the structural parameters, metallization and structural transition pressures are in reasonable agreement with experimental results. Although the calculated band gap within GGA shows substantial improvement over LDA, it is still lower than the measured ones. There is a speculation that at least part of this discrepancy is due to the discontinuity inherent in the exchange-correlation potential. The partial contribution from each atom to the total density of states is calculated. It is seen that the lower valence bands are mainly formed by s orbitals of Te, while the upper valence bands are formed by the p orbitals of Te. Empty states of the conduction bands are mainly formed by d orbitals of Ba.