Phase stability of the rare-earth sesquioxides under pressure
2009 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 80, no 10, 104105- p.Article in journal (Refereed) Published
The relative phase stability of the C- and A-type polymorphs of rare-earth sesquioxides RE2O3 (RE = La, Ce, Pr, Nd, Pm, Sm, Gd, Er, and Lu) under pressure have been studied by ab initio methods based on density-functional theory within the local-density approximation (LDA), and generalized gradient approximation. Both functionals show that the pressure of the C- to A-phase transition increases in the oxide series, although, the LDA results appear to be in better agreement with experimental data. The equation of states and pressure dependence of bulk modulus, c/a ratio and other structural parameters are analyzed. Our results indicate that the phase stability in these oxides to a large extend is determined by the electrostatic contribution to the total energy and it is related to the relaxation pattern of the structures.
Place, publisher, year, edition, pages
2009. Vol. 80, no 10, 104105- p.
IdentifiersURN: urn:nbn:se:uu:diva-127491DOI: 10.1103/PhysRevB.80.104105ISI: 000270383100023OAI: oai:DiVA.org:uu-127491DiVA: diva2:330424