标题： Ta$_2$O$_5$的可能正交相在高压下 显示英文标题

标题： Possible Orthorhombic Phase of Ta$_2$O$_5$ under High Pressures

摘要： 一种可能的正交相Ta$_2$O$_5$，被指定为Y-Ta$_2$O$_5$，在高压条件下通过密度泛函理论(DFT)计算结合结构搜索算法预测得出。该相每个晶胞包含四个公式单元($Z = 4$)，表现出最高的已知Ta-O配位数。 Y-Ta$_2$O$_5$被发现是在大约70 GPa到至少200 GPa的压力范围内Ta$_2$O$_5$的最有利的能量形式。 标准DFT-GGA和更高精度的GW计算都表明，Y-Ta$_2$O$_5$是一种宽禁带半导体，具有直接禁带。 此外，核量子效应 (NQEs) 在固定体积下对外部压力引入了非平凡的修正，强调了它们在高压相稳定性分析中的重要性。 显示英文摘要

摘要： A potential orthorhombic phase of Ta$_2$O$_5$, designated as Y-Ta$_2$O$_5$, is predicted under high-pressure conditions through density functional theory (DFT) calculations combined with structural search algorithms. This phase, consisting of four formula units per unit cell ($Z = 4$), exhibits the highest known Ta-O coordination numbers. Y-Ta$_2$O$_5$ is found to be the most energetically favorable form of Ta$_2$O$_5$ in the pressure range of approximately 70 GPa to at least 200 GPa. Both standard DFT-GGA and higher-accuracy GW calculations reveal that Y-Ta$_2$O$_5$ is a wide bandgap semiconductor with a direct bandgap. Additionally, nuclear quantum effects (NQEs) introduce nontrivial corrections to external pressure at fixed volumes, underscoring their significance in high-pressure phase stability analyses.