Delarmelina Maicon, Quesne Matthew G, Catlow C Richard A
School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, UK.
Phys Chem Chem Phys. 2020 Mar 25;22(12):6660-6676. doi: 10.1039/d0cp00032a.
We report a detailed survey of the calculated bulk properties of zirconia using GGA and meta-GGA functionals (PBE, PBEsol, RPBE, and TPSS), dispersion (Grimme's D2 and D3 approach), and on-site Coulomb repulsion correction (U = 2-8 eV). Structural, elastic, mechanical, and dielectric properties, as well as energetics, electronic structure, and phonon dispersion curves were computed and compared to previous investigations to identify the best DFT approach for a consistent in silico description of zirconia polymorphs. In general, inclusion of dispersion corrections led to only small changes in the calculated properties, whereas DFT+U (U = 2 or 4 eV) reduced the deviations of calculated properties from the experimental results, although deterioration of the structure and relative stabilities may be observed in some cases. Standard PBEsol, RPBE+U, and PBE+U were the best methodologies for a simultaneous description of the three polymorphs of ZrO2. RPBE+U, however, was the only functional to conserve the distinct structures and stabilities of c-, t-, and m-ZrO2 when U = 4 eV was used, resulting in the best in silico replication of the band gaps of ZrO2, whilst outperforming the other methodologies in the description of elastic, mechanical, and dielectric properties of this material. Overall, these results provide insight into the most appropriate DFT methodology for in silico investigations of ZrO2, and show that simultaneous description of all three ambient pressure zirconia polymorphs by DFT techniques with acceptable levels of accuracy can be achieved only when the correct choice of methodology is applied.
我们报告了一项使用广义梯度近似（GGA）和元广义梯度近似（meta-GGA）泛函（PBE、PBEsol、RPBE和TPSS）、色散校正（Grimme的D2和D3方法）以及在位库仑排斥校正（U = 2 - 8 eV）对氧化锆计算得到的体相性质进行的详细研究。计算了结构、弹性、力学和介电性质，以及能量学、电子结构和声子色散曲线，并与之前的研究进行比较，以确定用于对氧化锆多晶型进行一致的计算机模拟描述的最佳密度泛函理论（DFT）方法。一般来说，包含色散校正仅导致计算性质的微小变化，而DFT + U（U = 2或4 eV）减小了计算性质与实验结果的偏差，尽管在某些情况下可能会观察到结构和相对稳定性的恶化。标准PBEsol、RPBE + U和PBE + U是同时描述ZrO2三种多晶型的最佳方法。然而，当使用U = 4 eV时，RPBE + U是唯一能保持c -、t -和m - ZrO2不同结构和稳定性的泛函，从而在计算机模拟中得到ZrO2带隙的最佳复制，同时在描述该材料的弹性、力学和介电性质方面优于其他方法。总体而言，这些结果为ZrO2的计算机模拟研究提供了关于最合适的DFT方法的见解，并表明只有应用正确的方法选择，才能通过DFT技术以可接受的精度水平同时描述所有三种常压下的氧化锆多晶型。
