Zirconate pyrochlores under high pressure

Journal Article · Mon Jul 12 00:00:00 EDT 2010 · Physical Chemistry Chemical Physics. PCCP, 12(39):12472-12477

DOI:https://doi.org/10.1039/c0cp00278j· OSTI ID:991585

Xiao, Haiyan Y; Zhang, F X; Gao, Fei; Lang, Maik; Ewing, Rodney C; Weber, William J

Ab initio total-energy calculations and x-ray diffraction measurements have been combined to study the phase stability of zirconate pyrochlores (A2Zr2O7; A=La, Nd and Sm) under pressures up to 50 GPa. Phase transformations to the defect-cotunnite structure are theoretically predicted at pressures of 22, 20 and 18 GPa, in excellent agreement with the experimentally determined values of 21, 22 and 18 GPa for La2Zr2O7, Nd2Zr2O7 and Sm2Zr2O7, respectively. Analysis of the elastic properties indicates that elastic anisotropy may be one of the driving forces for the pressure-induced cubic-to-noncubic phase transformation.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 991585
• Report Number(s): PNNL-SA-73868; 34899; KC0201020; TRN: US201021%%222
• Journal Information: Physical Chemistry Chemical Physics. PCCP, 12(39):12472-12477, Vol. 12, Issue 39; ISSN 1463-9076
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ANISOTROPY
ELASTICITY
PHASE STABILITY
PHASE TRANSFORMATIONS
X-RAY DIFFRACTION
ZIRCONATES
pyrochlore
high pressure
phase stability
DFT
XRD
Environmental Molecular Sciences Laboratory