Experimental and Theoretical Identification of a New High-Pressure TiO2 Polymorph
Abstract
Our combined theoretical and experimental investigations have led to the discovery of a new polymorph of titanium dioxide, where titanium is seven-coordinated to oxygen in the orthorhombic OI ( Pbca) structure. The zero-pressure bulk modulus of the new phase measured in the pressure range 19 to 36 GPa is 318(3) GPa. We demonstrate that the group IVa dioxides ( TiO2, ZrO2, HfO2) on compression at ambient temperature all follow the common path: rutile -->α-PbO2-type --> baddeleyite-type (MI) --> orthorhombic OI ( Pbca) structure --> cotunnite-type (OII).
- Publication:
-
Physical Review Letters
- Pub Date:
- December 2001
- DOI:
- 10.1103/PhysRevLett.87.275501
- Bibcode:
- 2001PhRvL..87A5501D