TY - JOUR

T1 - The Hubbard U correction for iron-bearing minerals

T2 - A discussion based on (Mg,Fe)SiO3 perovskite

AU - Hsu, Han

AU - Umemoto, Koichiro

AU - Cococcioni, Matteo

AU - Wentzcovitch, Renata M.

N1 - Funding Information:
This work was supported primarily by the MRSEC Program of the National Science Foundation under Award Number DMR-0212302 and DMR-0819885. It was also supported by NSF grants ATM-0426757 (VLab) and EAR-0815446 . Calculations were performed at the Minnesota Supercomputing Institute (MSI).

PY - 2011/3

Y1 - 2011/3

N2 - Using iron-bearing magnesium silicate perovskite as an example, we show that the Hubbard U correction is not always necessary for calculating the structural and elastic properties of iron-bearing minerals. Instead, it is the choice of DFT functionals (LDA or GGA) that may have greater impact on the quality of the predictive calculation. For iron-bearing minerals, calculations adopting LDA (LDA+U) are generally in better agreement with experimental data than those adopting GGA (GGA+U) after including zero point motion and thermal vibrational effects, as demonstrated by the room-temperature compression curve of (Mg,Fe)SiO3 perovskite. A criterion indicating the necessity of the Hubbard U correction is also discussed. As long as the standard DFT functional produces insulating ground state with correct orbital occupancy, the Hubbard U correction does not affect the computed structural and elastic properties.

AB - Using iron-bearing magnesium silicate perovskite as an example, we show that the Hubbard U correction is not always necessary for calculating the structural and elastic properties of iron-bearing minerals. Instead, it is the choice of DFT functionals (LDA or GGA) that may have greater impact on the quality of the predictive calculation. For iron-bearing minerals, calculations adopting LDA (LDA+U) are generally in better agreement with experimental data than those adopting GGA (GGA+U) after including zero point motion and thermal vibrational effects, as demonstrated by the room-temperature compression curve of (Mg,Fe)SiO3 perovskite. A criterion indicating the necessity of the Hubbard U correction is also discussed. As long as the standard DFT functional produces insulating ground state with correct orbital occupancy, the Hubbard U correction does not affect the computed structural and elastic properties.

KW - First-principles

KW - GGA+U

KW - Hubbard U

KW - Iron-bearing minerals

KW - LDA+U

KW - Lower mantle

UR - http://www.scopus.com/inward/record.url?scp=79952315962&partnerID=8YFLogxK

U2 - 10.1016/j.pepi.2010.12.001

DO - 10.1016/j.pepi.2010.12.001

M3 - 期刊論文

AN - SCOPUS:79952315962

VL - 185

SP - 13

EP - 19

JO - Physics of the Earth and Planetary Interiors

JF - Physics of the Earth and Planetary Interiors

SN - 0031-9201

IS - 1-2

ER -