Modeling the effect of zinc oxide on the electronic properties of polyvinyl alcohol

Abstract

A Computational study for the physical properties of polyvinyl alcohol (PVA) in its emeraldine base form (4PVA) is presented. Both PM6 semiempirical and DFT: B3LYP/LANL2DZ levels are conducted to elucidate the ZnO effects on the electronic and surface properties of PVA. The influence of ZnO was introduced in terms of total dipole moment (TDM), HOMO/LUMO band gap energy (ΔE) and molecular electrostatic potential (MESP). The results indicated that, TDM of 4PVA and ΔE were changed by changing the interaction site. Where, the band gap energy of 4PVA decreased sharply with ZnO addition and the electron density together with the reactivity was increased as presented in MESP maps. Also, the influence of ZnO addition was clearly observed from TDM and ΔE values calculated with DFT than those calculated at PM6 level. The difference between both methods could be attributed to electron correlation which is included in DFT rather than PM6, this makes DFT more accurate than PM6.