Phase Stability and Pressure Dependence of Defect Formation in Gd2Ti2O7 and Gd2Zr2O7 Pyrochlore

Journal Article · Tue Jan 01 00:00:00 EST 2008 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.100.045503· OSTI ID:959522

Zhang, F; Wang, J; Lian, J; Lang, M; Becker, U; Ewing, R

We report dramatically different behaviors between isostructural Gd2Ti2O7 and Gd2Zr2O7 pyrochlore at pressures up to 44 GPa, in which the substitution of Ti for Zr significantly increases structural stability. Upon release of pressure, the Gd2Ti2O7 becomes amorphous. In contrast, the high-pressure phase of Gd2Zr2O7 transforms to a disordered defect-fluorite structure. First-principle calculations for both compositions revealed that the response of pyrochlore to high pressure is controlled by the intrinsic energetics of defect formation.

• Research Organization: Brookhaven National Lab. (BNL), Upton, NY (United States). National Synchrotron Light Source
• Sponsoring Organization: Doe - Office Of Science
• DOE Contract Number: DE-AC02-98CH10886
• OSTI ID: 959522
• Report Number(s): BNL-82508-2009-JA; PRLTAO; TRN: US201016%%666
• Journal Information: Physical Review Letters, Vol. 100, Issue 4; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
DEFECTS
PHASE STABILITY
PRESSURE DEPENDENCE
PYROCHLORE
STABILITY
national synchrotron light source