The stability and equation of state for the cotunnite phase of TiO2 up to 70 GPa

@article{NishioHamane2010TheSA,
  title={The stability and equation of state for the cotunnite phase of TiO2 up to 70 GPa},
  author={Daisuke Nishio-Hamane and Asa Shimizu and Ritsuko Nakahira and Ken Niwa and Asami Sano-Furukawa and Taku Okada and Takehiko Yagi and Takumi Kikegawa},
  journal={Physics and Chemistry of Minerals},
  year={2010},
  volume={37},
  pages={129-136}
}
The stability and equation of state for the cotunnite phase in TiO2 were investigated up to a pressure of about 70 GPa by high-pressure in situ X-ray diffraction measurements using a laser-heated diamond anvil cell. The transition sequence under high pressure was rutile → α-PbO2 phase → baddeleyite phase → OI phase → cotunnite phase with increasing pressure. The cotunnite phase was the most stable phase at pressures from 40 GPa to at least 70 GPa. The equation of state parameters for the… Expand
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TLDR
A new study on the pressure-induced phase transitions of TiO(2) has been performed using all-electron density-functional theory based computations with the projector augmented wave and the linearized augmented plane wave methods, and it is said that the cotunnite phase is not a superhard TiO (2) polymorph as has been suggested previously. Expand
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