Pressure-induced phase transitions and electronic properties Cd2V2O7
arXiv:2205.10258 · doi:10.1039/D2RA01717B
Abstract
We report a density-functional theory study of the structural and electronic properties of Cd2V2O7 under high-pressure conditions. The calculations have been performed by using first-principle calculations with the CRYSTAL program. The occurrence of two structural phase transitions, at 0.3 and 10.9 GPa, is proposed. The crystal structure of the different high-pressure phases is reported. Interestingly a cubic pyrochlore-type structure is predicted to stabilize under compression. The two phase transitions involve substantial changes in the coordination polyhedra of Cd and V. We have also determined the compressibility and room-temperature equation of state of the three polymorphs of Cd2V2O7. According to our systematic electronic band-structure calculations, at ambient conditions Cd2V2O7 is an indirect wide band-gap material with a band-gap energy of 4.39 eV. In addition, the pressure dependence of the band gap has been determined. In particular, we have found that after the second phase transition the band gap decreases abruptly to a value of 2.56 eV.
arXiv comment29 pages, 8 figures, 5 tables
References in corpus (9)
- Perspective on density functional theory
- PASCal: A principal-axis strain calculator for thermal expansion and compressibility determination
- Pressure effects on the structural and electronic properties of ABX4 scintillating crystals
- The electronic structure of zircon-type orthovanadates: Effects of high-pressure and cation substitution
- Recent progress on the characterization of the high-pressure behaviour of AVO4 orthovanadates
- Tuning the band gap of PbCrO4 through high-pressure: Evidence of wide-to-narrow semiconductor transitions
- Comparative study of the high-pressure behavior of ZnV2O6, Zn2V2O7, and Zn3V2O8
- High pressure crystal structures of orthovanadates and their properties
- New Pressure-Induced Polymorphic Transitions of Anhydrous Magnesium Sulfate