Brandenburg Jan Gerit, Maas Tilo, Grimme Stefan
Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms Universität Bonn, Beringstraße 4, 53115 Bonn, Germany.
J Chem Phys. 2015 Mar 28;142(12):124104. doi: 10.1063/1.4916070.
Water in different phases under various external conditions is very important in bio-chemical systems and for material science at surfaces. Density functional theory methods and approximations thereof have to be tested system specifically to benchmark their accuracy regarding computed structures and interaction energies. In this study, we present and test a set of ten ice polymorphs in comparison to experimental data with mass densities ranging from 0.9 to 1.5 g/cm(3) and including explicit corrections for zero-point vibrational and thermal effects. London dispersion inclusive density functionals at the generalized gradient approximation (GGA), meta-GGA, and hybrid level as well as alternative low-cost molecular orbital methods are considered. The widely used functional of Perdew, Burke and Ernzerhof (PBE) systematically overbinds and overall provides inconsistent results. All other tested methods yield reasonable to very good accuracy. BLYP-D3(atm) gives excellent results with mean absolute errors for the lattice energy below 1 kcal/mol (7% relative deviation). The corresponding optimized structures are very accurate with mean absolute relative deviations (MARDs) from the reference unit cell volume below 1%. The impact of Axilrod-Teller-Muto (atm) type three-body dispersion and of non-local Fock exchange is small but on average their inclusion improves the results. While the density functional tight-binding model DFTB3-D3 performs well for low density phases, it does not yield good high density structures. As low-cost alternative for structure related problems, we recommend the recently introduced minimal basis Hartree-Fock method HF-3c with a MARD of about 3%.
在各种外部条件下，不同相态的水在生化系统以及表面材料科学中都非常重要。密度泛函理论方法及其近似方法必须针对具体系统进行测试，以评估其在计算结构和相互作用能方面的准确性。在本研究中，我们展示并测试了一组十种冰多晶型物，并与实验数据进行比较，这些冰多晶型物的质量密度范围为0.9至1.5 g/cm³，且包括对零点振动和热效应的显式校正。我们考虑了广义梯度近似（GGA）、meta-GGA和杂化水平下包含伦敦色散的密度泛函以及其他低成本分子轨道方法。广泛使用的Perdew、Burke和Ernzerhof（PBE）泛函系统性地过度结合，总体上给出不一致的结果。所有其他测试方法的准确性从合理到非常好。BLYP-D3(atm)给出了出色的结果，晶格能的平均绝对误差低于1 kcal/mol（相对偏差7%）。相应的优化结构非常准确，与参考晶胞体积的平均绝对相对偏差（MARDs）低于1%。Axilrod-Teller-Muto（atm）型三体色散和非局部福克交换的影响较小，但总体而言，包含它们会改善结果。虽然密度泛函紧束缚模型DFTB3-D3在低密度相表现良好，但对于高密度结构却不能给出良好的结果。作为与结构相关问题的低成本替代方法，我们推荐最近引入的最小基哈特里-福克方法HF-3c，其MARD约为3%。
