Exploring electronic properties of zinc oxide using pure and hybrid density functional theory and Compton profiles

Abstract

To check the viability and applicability of available experimental Compton profiles (CPs) of ZnO, we have computed Mulliken population (MP) and CPs using pure and hybrid density functional theory (DFT) within the basis of linear combination of atomic orbitals (LCAO) scheme. Pure DFT have been employed within local density approximation, generalized gradient approximation (GGA) and second order GGA (SOGGA) whereas for hybrid exchange and correlation energies the standard WC1LYP and B1WC hybrid schemes are adopted. A quantitative comparison of theoretical and the available experimental CPs unambiguously identify WC1LYP as a better choice for reproducing experimental momentum densities, and thereafter hybrid approach for generating accurate Eigen functions of ZnO. Further, MP analysis reports the dominancy of ionic character in the compounds. We have also scaled the CPs of ZnO and CdO using WC1LYP for equal-valence-electron-densities and concluded about more ionic character in ZnO than that in CdO.