First principles calculations of Cd and Zn chalcogenides with modified Becke–Johnson density potential

In this work, we present first principles calculations based on a full potential linear augmented plane-wave method (FP-LAPW) to calculate structural and electronic properties of CdX and ZnX (X = S, Se, Te) based II–VI chalcogenides. First principles calculations using the local density approximation (LDA) and the related generalized gradient approximation (GGA) lead to a severe underestimate of the band gap. The proposed model uses various exchange–correlation potentials (LSDA, GGA and MBJLDA) to determine band gaps and structural properties of semiconductors. We show that using modified Becke–Johnson (MBJLDA) density potential leads to a better agreement with experimental data for band gaps of Cd and Zn based semiconductors.

► We calculate structural and electronic properties of Cd and Zn chalgonides. ► Our calculation procedure involves modified Becke–Johnson density functional. ► It gives a better agreement with experiment for band gap and lattice constant.