Efectos de intercambio y correlación en las propiedades estructurales y electrónicas del TiO2 en la fase rutilo.

In this work, we study the structural and electronic properties of TiO2 in the rutile phase based on first principles calculations. The electronic exchange and correlation effects were studied using functionals in the local density approximation (LDA), the generalized gradient approximation (GGA) by Perdew-Burke- Ernzerhof (PBE), Perdew-Burke-Ernzerhof revised for solids (PBEsol), Perdew-Wang 91 (PW91) and revised Perdew-Burke-Ernzerhof (rPBE), and the meta-generalized gradient approximation (meta-GGA) by Tao-Perdew-Staroverov-Scuseria (TPSS) and revised-TPSS (RTPSS) in the frame of the Density Functional Theory (DFT). We found that the PBEsol functional provides better results for the lattice parameter values (a y c) and the equatorial and axial lengths (deq and dax); while for the cohesion energy (Ecoh), volumetric module (B0) and angles (2q y a) the PBE, rPBE and TPSS functionals respectively, are closer to the experimental values. It is confirmed that the TiO2 presents properties of direct semiconductor in Γ-Γ. [ABSTRACT FROM AUTHOR]