New ring-like models and<i>ab initio</i>DFT study of the medium-range structures, energy and electronic properties of GeSe₂glass

Abstract

Abstract Ab initio DFT calculations were performed on GenSem nanoclusters (n = 2, 3, 5, 6, 12; m = 6–9, 14, 16, 30) that represent the local structure of GeSe2 glass and on some 'defect' GenSem clusters that are thought to be related to the inhomogeneity of the structure at the nanoscale. The optimal geometries, total energies and their derivatives as well as the electronic properties of GenSem nanoclusters were calculated using traditional DFT method. In addition, the TD-DFT method has been applied to calculate the electronic band gaps of the clusters. The calculated physico-chemical properties of GenSem nanoclusters and their couplings with the local-and medium-range order structure formations in GeSe2 glass are analysed and discussed. Keywords: ab initio DFTGeSe2 glassfinite clusters Acknowledgment This work was performed within Ukrainian-Turkish collaboration in Science and Technology (Project Numbers M85-2010 and TUBITAK-109T643).