Experimental and Theoretical Identification of a New High-Pressure <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>TiO</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span> Polymorph

Natalia A. Dubrovinskaia; Leonid S. Dubrovinsky; Rajeev Ahuja; Vitaly B. Prokopenko; V. Dmitriev; H.-P. Weber; J. M. Osorio-Guillen; Börje Johansson

doi:10.1103/PhysRevLett.87.275501

Experimental and Theoretical Identification of a New High-Pressure ${TiO}_{2}$ Polymorph

Natalia A. Dubrovinskaia, Leonid S. Dubrovinsky, Rajeev Ahuja, Vitaly B. Prokopenko, V. Dmitriev, H.-P. Weber, J. M. Osorio-Guillen, and Börje Johansson

Phys. Rev. Lett. 87, 275501 – Published 7 December 2001

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 ( ${TiO}_{2}$ , ${ZrO}_{2}$ , ${HfO}_{2}$ ) on compression at ambient temperature all follow the common path: rutile $\to α - {PbO}_{2}$ -type $\to$ baddeleyite-type (MI) $\to$ orthorhombic OI ( $Pbca$ ) structure $\to$ cotunnite-type (OII).

Received 23 March 2001

DOI:https://doi.org/10.1103/PhysRevLett.87.275501

Authors & Affiliations

Natalia A. Dubrovinskaia¹, Leonid S. Dubrovinsky¹, Rajeev Ahuja², Vitaly B. Prokopenko³, V. Dmitriev⁴, H.-P. Weber⁴, J. M. Osorio-Guillen², and Börje Johansson²

¹Bayerisches Geoinstitut, Universität Bayreuth, D-95440 Bayreuth, Germany
²Department of Physics, Uppsala University, S-751 21 Uppsala, Sweden
³Consortium for Advanced Radiation Sources, The University of Chicago, Chicago, Illinois 60637
⁴SNBL, European Synchrotron Radiation Facility, Grenoble 38043, France