Vega Lorena, Viñes Francesc
Departament de Ciència de Materials i Química Física & Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, Barcelona, Spain.
J Comput Chem. 2020 Nov 15;41(30):2598-2603. doi: 10.1002/jcc.26415. Epub 2020 Sep 9.
Perdew-Burke-Ernzerhof (PBE) and PBE adapted for solids (PBEsol) are exchange-correlation (xc) functionals widely used in density functional theory simulations. Their differences are the exchange, μ, and correlation, β, coefficients, causing PBEsol to lose the Local Spin Density (LSD) response. Here, the μ/β two-dimensional (2D) accuracy landscape is analyzed between PBE and PBEsol xc functional limits for 27 transition metal (TM) bulks, as well as for 81 TM surfaces. Several properties are analyzed, including the shortest interatomic distances, cohesive energies, and bulk moduli for TM bulks, and surface relaxation degree, surface energies, and work functions for TM surfaces. The exploration, comparing the accuracy degree with respect experimental values, reveals that the found xc minimum, called VV, being a PBE variant, represents an improvement of 5% in mean absolute percentage error terms, whereas this improvement reaches ~11% for VVsol, a xc resulting from the restoration of LSD response in PBEsol, and so regarded as its variant.
佩德韦-伯克-恩泽霍夫（PBE）和适用于固体的PBE（PBEsol）是密度泛函理论模拟中广泛使用的交换关联（xc）泛函。它们的区别在于交换系数μ和关联系数β，这使得PBEsol失去了局域自旋密度（LSD）响应。在此，分析了PBE和PBEsol xc泛函极限之间27种过渡金属（TM）体相以及81个TM表面的μ/β二维（2D）精度态势。分析了几种性质，包括TM体相的最短原子间距离、内聚能和体模量，以及TM表面的表面弛豫度、表面能和功函数。通过与实验值比较精度程度的探索发现，所找到的xc最小值称为VV，它是PBE的一个变体，在平均绝对百分比误差方面提高了5%，而对于VVsol，即通过恢复PBEsol中的LSD响应得到的一个xc，因此被视为其变体，这一改进达到了约11%。
