Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany.
Phys Rev Lett. 2012 Oct 5;109(14):146402. doi: 10.1103/PhysRevLett.109.146402. Epub 2012 Oct 4.
The isostructural α-γ phase transition in cerium is analyzed using density-functional theory with different exchange-correlation functionals, in particular the PBE0 hybrid functional and the exact-exchange plus correlation in the random-phase approximation [(EX+cRPA)@PBE0] approach. We show that the Hartree-Fock exchange part of the hybrid functional gives rise to two distinct solutions at zero temperature that can be associated with the α and γ phases of cerium. However, despite the relatively good structural and magnetic properties, PBE0 predicts the γ phase to be the stable phase at ambient pressure and zero temperature, in contradiction with low temperature experiments. EX+cRPA reverses the energetic ordering, which emphasizes the importance of correlation for rare-earth systems.
使用不同交换关联泛函（特别是 PBE0 杂化泛函和随机相位近似中的精确交换加相关 [(EX+cRPA)@PBE0] 方法）对铈的同构 α-γ 相转变进行了密度泛函理论分析。我们表明，杂化泛函的哈特ree-fock 交换部分在零温度下产生了两个不同的解，这两个解可以与铈的 α 和 γ 相相关联。然而，尽管 PBE0 具有相对较好的结构和磁性性质，但它预测 γ 相在环境压力和零温度下是稳定的，这与低温实验相矛盾。EX+cRPA 反转了能量排序，这强调了关联对于稀土系统的重要性。
