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

  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},
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… 
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