Details
| Original language | English |
|---|---|
| Pages (from-to) | 1263-1278 |
| Number of pages | 16 |
| Journal | Zeitschrift fur Physikalische Chemie |
| Volume | 231 |
| Issue number | 7-8 |
| Publication status | Published - 26 Jul 2017 |
Abstract
In many applications it has been found that the standard generalized gradient approximation (GGA) does not accurately describe weak chemical bond and electronic properties of solids containing transition metals. In this work, we have considered the intercalation material 1T-LixTiS2 (0≤x≤1) as a model system for the evaluation of the accuracy of GGA and corrected GGA with reference to the availabile experimental data. The influence of two different dispersion corrections (D3 and D-TS) and an on-site Coulomb repulsion term (GGA+U) on the calculated structural and electronic properties is tested. All calculations are based on the Perdew-Burke-Ernzerhof (PBE) functional. An effective U value of 3.5 eV is used for titanium. The deviation of the calculated lattice parameter c for TiS2 from experiment is reduced from 14 % with standard PBE to -2 % with PBE+U and Grimme's D3 dispersion correction. 1T-TiS2 has a metallic ground state at PBE level whereas PBE+U predicts an indirect gap of 0.19 eV in agreement with experiment. The 7Li chemical shift and quadrupole coupling constants are in reasonable agreement with the experimental data only for PBE+U-D3. An activation energy of 0.4 eV is calculated with PBE+U-D3 for lithium migration via a tetrahedral interstitial site. This result is closer to experimental values than the migration barriers previously obtained at LDA level. The proposed method PBE+U-D3 gives a reasonable description of structural and electronic properties of 1T-LixTiS2 in the whole range 0≤x≤1.
Keywords
- band structure, chemical shift, DFT+U, dispersion correction, Li ion diffusion, lithium titanium disulfide, migration barrier, quadrupole coupling constant
ASJC Scopus subject areas
- Chemistry(all)
- Physical and Theoretical Chemistry
Cite this
- Standard
- Harvard
- Apa
- Vancouver
- BibTeX
- RIS
In: Zeitschrift fur Physikalische Chemie, Vol. 231, No. 7-8, 26.07.2017, p. 1263-1278.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Density Functional Theory Evaluated for Structural and Electronic Properties of 1T-LixTiS2 and Lithium Ion Migration in 1T-Li0.94TiS2
AU - Werth, Vanessa
AU - Volgmann, Kai
AU - Islam, Mazharul M.
AU - Heitjans, Paul
AU - Bredow, Thomas
N1 - Publisher Copyright: © 2017 Walter de Gruyter GmbH, Berlin/Boston 2017. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2017/7/26
Y1 - 2017/7/26
N2 - In many applications it has been found that the standard generalized gradient approximation (GGA) does not accurately describe weak chemical bond and electronic properties of solids containing transition metals. In this work, we have considered the intercalation material 1T-LixTiS2 (0≤x≤1) as a model system for the evaluation of the accuracy of GGA and corrected GGA with reference to the availabile experimental data. The influence of two different dispersion corrections (D3 and D-TS) and an on-site Coulomb repulsion term (GGA+U) on the calculated structural and electronic properties is tested. All calculations are based on the Perdew-Burke-Ernzerhof (PBE) functional. An effective U value of 3.5 eV is used for titanium. The deviation of the calculated lattice parameter c for TiS2 from experiment is reduced from 14 % with standard PBE to -2 % with PBE+U and Grimme's D3 dispersion correction. 1T-TiS2 has a metallic ground state at PBE level whereas PBE+U predicts an indirect gap of 0.19 eV in agreement with experiment. The 7Li chemical shift and quadrupole coupling constants are in reasonable agreement with the experimental data only for PBE+U-D3. An activation energy of 0.4 eV is calculated with PBE+U-D3 for lithium migration via a tetrahedral interstitial site. This result is closer to experimental values than the migration barriers previously obtained at LDA level. The proposed method PBE+U-D3 gives a reasonable description of structural and electronic properties of 1T-LixTiS2 in the whole range 0≤x≤1.
AB - In many applications it has been found that the standard generalized gradient approximation (GGA) does not accurately describe weak chemical bond and electronic properties of solids containing transition metals. In this work, we have considered the intercalation material 1T-LixTiS2 (0≤x≤1) as a model system for the evaluation of the accuracy of GGA and corrected GGA with reference to the availabile experimental data. The influence of two different dispersion corrections (D3 and D-TS) and an on-site Coulomb repulsion term (GGA+U) on the calculated structural and electronic properties is tested. All calculations are based on the Perdew-Burke-Ernzerhof (PBE) functional. An effective U value of 3.5 eV is used for titanium. The deviation of the calculated lattice parameter c for TiS2 from experiment is reduced from 14 % with standard PBE to -2 % with PBE+U and Grimme's D3 dispersion correction. 1T-TiS2 has a metallic ground state at PBE level whereas PBE+U predicts an indirect gap of 0.19 eV in agreement with experiment. The 7Li chemical shift and quadrupole coupling constants are in reasonable agreement with the experimental data only for PBE+U-D3. An activation energy of 0.4 eV is calculated with PBE+U-D3 for lithium migration via a tetrahedral interstitial site. This result is closer to experimental values than the migration barriers previously obtained at LDA level. The proposed method PBE+U-D3 gives a reasonable description of structural and electronic properties of 1T-LixTiS2 in the whole range 0≤x≤1.
KW - band structure
KW - chemical shift
KW - DFT+U
KW - dispersion correction
KW - Li ion diffusion
KW - lithium titanium disulfide
KW - migration barrier
KW - quadrupole coupling constant
UR - http://www.scopus.com/inward/record.url?scp=85024894394&partnerID=8YFLogxK
U2 - 10.1515/zpch-2016-0919
DO - 10.1515/zpch-2016-0919
M3 - Article
AN - SCOPUS:85024894394
VL - 231
SP - 1263
EP - 1278
JO - Zeitschrift fur Physikalische Chemie
JF - Zeitschrift fur Physikalische Chemie
SN - 0942-9352
IS - 7-8
ER -