论文标题
在高压下Bazro3的四方相的稳定性
Stability of the tetragonal phase of BaZrO3 under high pressure
论文作者
论文摘要
在本文中，我们通过在高压下的第一原则计算，拉曼光谱和X射线衍射的结合来重新审视Bazro3的高压行为。我们通过实验确认10 GPA的立方到四方过渡，并找不到任何其他相过渡到45 GPA的证据，这是所研究的最高压力，随着过去的报告而变化。我们以密度功能理论重新调查了相位稳定性，不仅要考虑已知的四方（I4/MCM）相，而且考虑其他潜在的抗铁病态候选者。这表明，与具有更复杂的倾斜系统相比，在压力增加时，四方相在增加压力时逐渐稳定。因此，排除了第二次过渡到另一个倾斜阶段的可能性，尤其是非常常见的原骨PNMA结构。
In this paper, we revisit the high-pressure behavior of BaZrO3 by a combination of first-principle calculations, Raman spectroscopy, and x-ray diffraction under high pressure. We confirm experimentally the cubic-to-tetragonal transition at 10 GPa and find no evidence for any other phase transition up to 45 GPa, the highest pressures investigated, at variance with past reports. We re-investigate phase stability with density functional theory considering not only the known tetragonal (I4/mcm) phase but also other potential antiferrodistortive candidates. This shows that the tetragonal phase becomes progressively more stable upon increasing pressure as compared to phases with more complex tilt systems. The possibility for a second transition to another tilted phase at higher pressures, and in particular to the very common orthorhombic Pnma structure, is therefore ruled out.
