Electronic Structure and Momentum Density of BaO and BaS

R Kumar,B K Sharma,G Sharma

doi:10.1155/2013/415726

Abstract

The electronic structure and electron momentum density distribution in BaO and BaS are presented using Compton spectroscopy. The first-ever Compton profile measurements on polycrystalline BaO and BaS were performed using 59.54 keV gamma-rays. To interpret the experimental data, we have computed the theoretical Compton profiles of BaO and BaS using the linear combination of atomic orbitals method. In the present computation, the correlation scheme proposed by Perdew-Burke-Ernzerhof and the exchange scheme of Becke were considered. The hybrid B3PW and Hartree-Fock based profiles were also computed for both compounds. The ionic configurations are performed to estimate the charge transfer on compound formation, and the present study suggests charge transfer from Ba to O and S atoms. On the basis of equal-valence-electron-density profiles, it is found that BaO is more ionic as compared to BaS.

Highlights

The II–VI alkaline earth compounds have interesting bond characteristics and simple crystal structures
Lin et al [8] observed that the electronic structure of these compounds containing oxygen atoms always obeys a different relationship from the compounds not containing oxygen atoms using density functional theory (DFT)
The theoretical ionic profiles of BaO and BaS for various charge transfer configurations were calculated from the free atom Compton profiles of Ba, O, and S atoms [22]

Summary

Introduction

The II–VI alkaline earth compounds have interesting bond characteristics and simple crystal structures. Most of the earlier studies, both experimental and theoretical, involve the electronic, optical, and structural properties of BaO and BaS [5,6,7,8,9,10,11,12,13,14,15]. To the best of our knowledge, no one attempted the electronic structure and momentum density of BaO and BaS using Compton spectroscopy. It is well established that Compton spectroscopy provides a useful test to examine the bonding in solids [16, 17] We found it worth to study the electronic structure in BaO and BaS using Compton profile.

Experimental Details and Data Analysis

Theoretical Details

Results and Discussion

Conclusions