A DFT + U study on structural, electronic, vibrational and thermodynamic properties of TiO 2 polymorphs and hydrogen titanate: tuning the Hubbard ‘ U -term’

Authors
German, Estefania; Faccio Sgiorovello, Ricardo Juan; Mombrú, Alvaro W
Publication Year
2017
Language
English
Format
article
Status
Published version
Description
Structural, electronic, vibrational and thermodynamic properties have been tested when Hubbard parameter U is implemented in density functional theory calculations for TiO2 polymorphs: anatase, rutile, TiO2?B and for hydrogen titanate (H2Ti3O7) bulk. Optimum U parameter values were found for each system, balancing geometric changes and electronic properties, namely, U = 4 eV for anatase and TiO2?B, U = 5 eV for rutile and hydrogen titanate. Although the addition of this parameter improves the prediction of electronic properties, with no significant structural changes, we found that it would not be adequate for predicting vibrational properties.
Fil: German, Estefania. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; Argentina. Universidad de la República; Uruguay
Fil: Faccio Sgiorovello, Ricardo Juan. Universidad de la República; Uruguay
Fil: Mombrú, Alvaro W. Universidad de la República; Uruguay
Subject
DFT
HUBBARD
TIO2
THERMODYNAMIC PROPERTIES
Astronomía
Ciencias Físicas
CIENCIAS NATURALES Y EXACTAS
Access level
Open access
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/63570