First principles study on structural, phase transition and electronic structure of Zinc Sulfide (ZnS) within LDA, GGA and mBJ potential

摘要

Anab-initiocalculationbasedonfullpotentiallinearisedaugmentedplanewavemethodofdensityfunctionaltheory(DFT)withinthelocaliseddensityapproximation(LDA),generalisedgradientapproximation(GGA)andmodifiedBecke-Johnson(mBJ)forexchangecorrelationpotentialisperformedtoinvestigatethestructural,phasetransitionandelectronicstructureofZincSulfide(ZnS).AcomparativestudyisperformedforthethreeapproximationsandrevealthatcalculationswithintheGGAgivesbetterstructuralstabilityandphasetransitionpressureof17.6GPainreasonablycloseagreementtoexperimentalresults.TheelectronicstructurecalculationwithinmBJpredictshigherdirectbandgapof3.5eVincomparisontoLDAandGGAunderestimatedvalue.ThetrendintheaccuracyofenergybandgapcalculationisfoundtobeLDAGGAmBJ-GGA.Theelectronicbandstructuresareinvestigatedusingthetotalandpartialdensityofstates...