8-12 July 2013
Structural and electronic properties of chalcopyrite AlAgX2 and AlCuX2(X= S, Se, Te)
Presented by Mr. Guy Moise DONGHO NGUIMDO on 9 Jul 2013 from 17:40 to 18:40
Type: Poster Presentation
Track: Track A - Division for Condensed Matter Physics and Materials
A selection of ternary compounds AlAgX2 and AlCuX2 (X= S, Se, Te), that may be potential components of solar cells were investigated. First principles Density Functional Theory (DFT) calculations for bulk structural and electronic properties were performed with three different approximations for the exchange- correlation energy. 1. The Generalized Gradient Approximation (GGA) by Perdew, Burke and Ernzerhof (PBE) . 2. The PBE DFT-D2 method of Grimme  which adds van der Walls interactions to PBE. 3. The vdW-DF2 approach of Langreth and Lundqvist  which includes van der Walls interactions and an optimised version of PBE. Results are given for the Equation of States (EOS), the optimized geometries, lattice constants, bulk moduli, and its pressure derivatives, Density of States (DOS) and band structures. The formation en- ergies, cohesive energies and elastics constant were used to predict the stability of the structures. We compared our results with previous works and experimental data. Potential components for solar cells, candidates for further numerical investigation, were identified based on structural stability and electronic structure properties.  John P. Perdew, Kieron Burke, Matthias Ernzerhof; Generalized Gradient Approximation Made Simple; Phys. Rev. Lett. 77, 3865 − 3868(1996).  Stefan Grimme; Semiempirical GGA-type density functional constructed with a long-range dispersion correction; Journal of Computational ChemistryVolume 27, Issue 15, pages 1787 − 1799, 30 November 2006.  Kyuho Lee1, Eamonn D. Murray, Lingzhu Kong, Bengt I. Lundqvist and David C. Langreth; Higher-accuracy van der Waals density functional ; Phys. Rev. B 82, 081101(R)(2010).