IFISUR   23398
INSTITUTO DE FISICA DEL SUR
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
SiO2(100) surface optimization by DFT calculations
Autor/es:
S. SIMONETTI; A. DIAZ COMPAÑY; A. LAM
Reunión:
Simposio; The Porous and Powder Materials Symposium and Exhibition; 2015
Resumen:
The development of modern theoretical surface science provides an opportunity to investigate structures on the atomic scale with useful applications in industrial technologies. Due to their high surface areas and pore volumes, mesoporous silicas have attracted great attention in novel applications. Mesoporous silica materials largely depend on the textural properties, such as pore diameters, pore volumes, particle morphology and surface modifications. In this work, a SiO2(100) surface has been optimized with calculations carried out in the framework of the Density Functional Theory (DFT) using the Vienna Ab-initio Simulation Package (VASP). In this code plane wave basis sets are used to solve the Kohn Sham equations. Electron exchange and correlation effects are described by the generalized gradient approximation (PBE). The electron-ion interactions are described by the projector-augmented wave (PAW) potentials. The fixed convergence of the plane-wave expansion was obtained with cut-off energy of 800 eV. This value is based on a previous test, which calculation error was lower than 0.01 eV. The two dimensional Brillouin integrations were full filled on a (3x3x1) Monkhorst-Packgrid and previously tested. The SiO2(100) optimum surface was represented with a periodically repeated slab containing seven layers of atoms.