Unraveling the role of V-V dimer on the vibrational properties of VO by first-principles simulations and Raman spectroscopic analysis
arXiv:2008.08725 · doi:10.1103/PhysRevB.103.214107
Abstract
We investigate the vibrational properties of VO2, particularly the low temperature M1 phase by first-principles calculations using the density functional theory as well as Raman spectroscopy. We perform the structural optimization using SCAN meta-GGA functional and obtain the optimized crystal structures for metallic rutile and insulating M1 phases satisfying all expected features of the experimentally derived structures. Based on the harmonic approximation around the optimized structures at zero temperature, we calculate the phonon properties and compare our results with experiments. We show that our calculated phonon density of states is in excellent agreement with the previous neutron scattering experiment. Moreover, we reproduce the phonon softening in the rutile phase as well as the phonon stiffening in the M1 phase. By comparing with the Raman experiments, we find that the Raman-active vibration modes of the M1 phase is strongly correlated with the V-V dimer distance of the crystal structure. Our combined theoretical and experimental framework demonstrates that Raman spectroscopy could serve as a reliable way to detect the subtle change of V-V dimer in the strained VO.
arXiv comment12 figures
References in corpus (20)
- Dynamical singlets and correlation-assisted Peierls transition in VO2
- Evidence for a Structurally-driven Insulator-to-metal Transition in VO2: a View from the Ultrafast Timescale
- Orbital-assisted metal-insulator transition in VO
- VO2: A Novel View from Band Theory
- Vanadium dioxide : A Peierls-Mott insulator stable against disorder
- Computation of the correlated metal-insulator transition in vanadium dioxide from first principles
- Correlation Assisted Phonon Softenings and the Mott-Peierls Transition in VO
- Mind the gap but also the spin: why the Heyd-Scuseria-Ernzerhof hybrid functional description of VO2 phases is not correct
- The insulating phases of vanadium dioxide are Mott-Hubbard insulators
- Unified Band Theoretic Description of Electronic and Magnetic Properties of Vanadium Dioxide Phases
- The role of defects in the metal-insulator transition in VO and VO
- The origin of the vanadium dioxide transition entropy
- Doping a Bad Metal: Origin of Suppression of Metal-Insulator Transition in Non-Stoichiometric VO
- Phonon localization in binary alloys with diagonal and off-diagonal disorder: A cluster Green's function approach
- Field-effect diode based on electron-induced Mott transition in NdNiO3
- Massively strained VO2 thin film growth on RuO2
- Physical properties of VTiO (0 x 0.187) single crystals
- Cooperative Effects of Strain and Electron Correlation in Epitaxial VO2 and NbO2
- Localization of phonons in mass disordered alloys - A typical medium dynamical cluster approach
- Epitaxial Growth and Electrical Properties of VO2 on LSAT (111) substrate