Vanadiumoxide
Last modified by jkkoskel@helsinki_fi on 2024/02/07 06:22
ESRF experiment performed at ID15B in 16.-22.5.2012
- Proposal
- Main proposer: Kari, other experimenters on site: Tuomas, Juho
- Older proposal (not accepted)
Structural details
- R phase (above ~340 K): metallic, tetragonal rutile structure, 2 formula units in unit cell
- M1 phase: monoclinic semiconductor, 4 formula units in unit cell
- 1st order phase transition, exp. latent heat 44 meV / formula unit (J.Phys.Chem.Solids 39, 941, 1978)
- Z [VO2]= 23+2*8 = 39 electrons
- VO2: Coefficient of linear thermal expansion
- alpha_ave = 5.7 10^-6 / K and 13.4 10^-6 / K at T = 298...334 K ja T = 339...360 K, respectively
Literature
- Older LDA study by Wentzcovitch, 1994
- Optimized LDA structures for R and M1 phases. Obtained energy difference: 54 meV.
- Eyert's review on VO2, Annalen der Physik 2002
- Eyert, PRL 2011
- VASP-PAW, cutoff 400 eV, nonmagnetic calculations, PBE and HSE
- Grau-Crespo et al, PRB 2012
- VASP-PAW, cutoff 400 eV, spin-polarized and nonmagnetic calculations, HSE, k-point grids 6x6x9 (R), 5x5x5 (M1)
- Gatti et al, PRL 2007
- scCOHSEX+G0W0, good agreement with experiments
- Older LDA study by Wentzcovitch, 1994