Author : Mohammed T. Hussein and Hamid A. Fayyadh

The electronic structure of (001)-(1×1) oxidized surface and core of II-VI zinc-blende CdSe0.5Te0.5 ternary semiconductor alloy Nano -crystals are investigated using Ab- initio Density functional theory (Ab-initio DFT) at the generalized-gradient approximation (GGA) level with STO-3G basis set coupled with large unit cell method(LUC). Calculations include only 8 core atoms 3D periodic boundary condition (PBC) and using 2D (PBC) with particular regard to the oxygenated (001)-(1×1) slab geometry surface. M any properties included total energy , cohesive energy, energy gap , valence and conduction bands width and density of states for core and surface part have been investigated, as well as the atomic charges of oxygenated (001)-(1×1) surface . The results obtained show that the energy gap and lattice constant of CdSe0.5Te0.5 nanocrystal for the surface part are smaller than of core part. Results show the energy gap for alloying composition CdSe0.5Te0.5 for 8 core atoms is equal to 2.545 eV, while it is equal to 0.032 eV for Cd8Se4Te4-O4 .

Keywords: Electronic Structure; CdSeTe Nano-crystals; Oxidized Surface.

Article published in International Journal of Current Engineering and Technology, Vol.6, No.5 (Oct-2016)