| EFFICIENCY OF AB-INITIO TOTAL ENERGY CALCULATIONS FOR METALS AND SEMICONDUCTORS USING A PLANE-WAVE BASIS SET |
| Paper ID : 1002-ISCH |
| Authors |
|
Idris Muhammad Chiromawa * Sule Lamido university Kafin hausa |
| Abstract |
| Spinel oxides have been predicted as one of the potential materials in many industrial applications and it opens the door for new technological applications including the possibility of transparent flexible electronics. First-principles calculations within the density functional theory (DFT) framework were employed and the Local density approximation (LDA) and generalized gradient approximation (GGA) approach were used to compute the equilibrium parameters. The bare DFT calculations showed that the energy bandgap of normal Fe2SiO4 fayalite using GGA-PBE and PBEsol as well as using LDA-PZ was found to be a metal even though experimentally it was found to be an insulator. Nevertheless incorporating the Hubbard correction parameter (U) due to the localized Fe-3d electrons produced the bandgap value to be close to available experimental data. The Hubbard parameter was computed for the Fe-3d in the Fe2SiO4 fayalite using the Cococcioni method as implemented in Quantum Espresso code. The value of U = 7.2 eV was found to be sufficient to correct the correlation effect in the considered material. The calculated band gaps for the Fe2SiO4 material are 3.84 eV, 3.66 eV and 3.56 eV using PBE+U, PBEsol+U and PZ+U respectively. Our result reveals the suitability of Fe2SiO4 fayalite for many optoelectronic and transparent conducting devices. |
| Keywords |
| Fe2SiO4 fayalite,; TCOs; optoelectronics; DFT |
| Status: Abstract Accepted (Oral Presentation) |