Ponencia en Cali

Published on: **Mar 4, 2016**

Published in:
Science

Source: www.slideshare.net

- 1. Ab initio study of the electronic properties of Mg1-xBiXO alloys Ph.D. (c) Patricia Abdel Rahim Bogotá, Colombia
- 2. Universidad de Tokio HPC in Asia Posters Young Asian and Australiasian researchers and graduate students showcase their latest research results, new projects and innovation to to a wider audience from Europe and the US at ISC’14, as well as to the HPC in Asia Session attendees who consist of top Asian scientists and researchers.
- 3. Índice • Introducción • Motivación • Nuestro trabajo
- 4. CsCl NaCl NiAs WZ ZnS
- 5. Ab initio study of the electronic properties of Mg1-xBiXO alloys Using the method in first-principles, we have investigated the electronic properties of the compound Mg1-xBixO with varying concentrations of 0%, 25%, 50% and 75% x of bismuth in the phases in sodium chloride (NaCl), cesium chloride (CsCl), zinc- blende (ZnB), wurtzite (WZ) and nickel arsenidine (NiAs) (including spin). We calculated the band structure and the density of states in the equilibrium volume of the structures for the different phases. The calculations were performed using the first-principles pseudo- potential method in the framework of the spin Density Functional Theory (DFT). The exchange and correlation effects are treated by using the Generalized Gradient Approximation (GGA) as it is implemented in the Perdew - Burke- Ernzerhof- method (PBE). The calculations were performed using the pwscf code, distributed with the Quantum-ESPRESSO package.
- 6. Structural parameters of Mg1-xBiXO alloys
- 7. Structural parameters of Mg1-xBiXO alloys
- 8. Transiciones de fase para esta estructura
- 9. Electronic properties of Mg1-xBiXO alloys in the phase NaCl MgO Mg0.75Bi0.25O Mg0.5Bi0.5O Mg0.25Bi0.75O
- 10. Electronic properties of Mg1-xBiXO alloys in the phase NaCl MgO Mg0.75Bi0.25O Mg0.5Bi0.5O Mg0.25Bi0.75O
- 11. Electronic properties of Mg1-xBiXO alloys in the phase WZ MgO Mg0.75Bi0.25O Mg0.5Bi0.5O Mg0.25Bi0.75O
- 12. Electronic properties of Mg1-xBiXO alloys in the phase WZ MgO Mg0.75Bi0.25O Mg0.5Bi0.5O Mg0.25Bi0.75O
- 13. Electronic properties of Mg1-xBiXO alloys in the phase ZnS MgO Mg0.75Bi0.25O Mg0.5Bi0.5O Mg0.25Bi0.75O
- 14. Electronic properties of Mg1-xBiXO alloys in the phase ZnS MgO Mg0.75Bi0.25O Mg0.5Bi0.5O Mg0.25Bi0.75O
- 15. Electronic properties of Mg1-xBiXO alloys in the phase CsCl MgO Mg0.75Bi0.25O Mg0.5Bi0.5O Mg0.25Bi0.75O
- 16. Electronic properties of Mg1-xBiXO alloys in the phase CsCl MgO Mg0.75Bi0.25O Mg0.5Bi0.5O Mg0.25Bi0.75O
- 17. Electronic properties of Mg1-xBiXO alloys in the phase NiAs MgO Mg0.75Bi0.25O Mg0.5Bi0.5O Mg0.25Bi0.75O
- 18. Electronic properties of Mg1-xBiXO alloys in the phase NiAs MgO Mg0.75Bi0.25O Mg0.5Bi0.5O Mg0.25Bi0.75O
- 19. Electronic properties of Mg1-xBiXO alloys in the phase Hexa MgO Mg0.75Bi0.25O Mg0.5Bi0.5O Mg0.25Bi0.75O
- 20. Conclusions Calculations of electronic properties of Mg1-xBixO were carried out by means of DFT using the Wu- Cohen GGA approximation. It was determined that the MgO has an energy gap the ~ 3 eV and other region down the ~ -1 eV formed mainly by the orbital p the O in the three phases studied and the Mg1-x BixO has a behavior metal for ¼, ½ and ¾ x of Bi in the phases the NaCl, CsCl, NaCl, WZ and ZnS.
- 21. Conclusiones Calculations of structural properties of Mg1-xBixO were carried out by means of DFT using the Wu- Cohen GGA approximation. It was determined that at concentrations of 25% there are no phase transitions, while for 100%, 75%, and of 50% x of Bi, if it exists, this can be very useful for future experimental studies of these materials. Furthermore, it was observed that decreasing the lattice constant makes the material become more rigid and hence increases the bulk modulus and the energy.
- 22. Muchas Gracias