jp5b05338_si_001.pdf (3.76 MB)
Investigating the Energetic Ordering of Stable and Metastable TiO2 Polymorphs Using DFT+U and Hybrid Functionals
journal contribution
posted on 2015-12-17, 09:34 authored by Matthew
T. Curnan, John R. KitchinPrediction of transition metal oxide
BO2 (B = Ti, V,
etc.) polymorph energetic properties is critical to tunable material
design and identifying thermodynamically accessible structures. Determining
procedures capable of synthesizing particular polymorphs minimally
requires prior knowledge of their relative energetic favorability.
Information concerning TiO2 polymorph relative energetic
favorability has been ascertained from experimental research. In this
study, the consistency of first-principles predictions and experimental
results involving the relative energetic ordering of stable (rutile),
metastable (anatase and brookite), and unstable (columbite) TiO2 polymorphs is assessed via density functional theory (DFT).
Considering the issues involving electron–electron interaction
and charge delocalization in TiO2 calculations, relative
energetic ordering predictions are evaluated over trends varying Ti
Hubbard U3d or exact exchange fraction
parameter values. Energetic trends formed from varying U3d predict experimentally consistent energetic ordering
over U3d intervals when using GGA-based
functionals, regardless of pseudopotential selection. Given pertinent
linear response calculated Hubbard U values, these
results enable TiO2 polymorph energetic ordering prediction.
Hybrid functional calculations involving rutile–anatase relative
energetics, though demonstrating experimentally consistent energetic
ordering over exact exchange fraction ranges, are not accompanied
by predicted fractions, for a first-principles methodology capable
of calculating exact exchange fractions precisely predicting TiO2 polymorph energetic ordering is not available.
History
Usage metrics
Categories
Keywords
pseudopotential selectionexchange fraction rangesMetastable TiO 2 PolymorphsU 3d intervalsTiO 2 calculationsTiO 2 polymorphTiO 2 polymorphsHubbard U valuestunable material designpredictionexchange fractionsHybrid FunctionalsPredictionEnergetic Orderingexchange fraction parameter valuescharge delocalizationDFTTi Hubbard U 3dtransition metal oxide BO 2Energetic trendsU 3d
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC