Mortazavi Majid, Brandenburg Jan Gerit, Maurer Reinhard J, Tkatchenko Alexandre
Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6, 14195 Berlin, Germany.
Department of Chemistry, University College London , 20 Gordon Street, WC1H 0AJ London, United Kingdom.
J Phys Chem Lett. 2018 Jan 18;9(2):399-405. doi: 10.1021/acs.jpclett.7b03234. Epub 2018 Jan 10.
Accurate prediction of structure and stability of molecular crystals is crucial in materials science and requires reliable modeling of long-range dispersion interactions. Semiempirical electronic structure methods are computationally more efficient than their ab initio counterparts, allowing structure sampling with significant speedups. We combine the Tkatchenko-Scheffler van der Waals method (TS) and the many-body dispersion method (MBD) with third-order density functional tight-binding (DFTB3) via a charge population-based method. We find an overall good performance for the X23 benchmark database of molecular crystals, despite an underestimation of crystal volume that can be traced to the DFTB parametrization. We achieve accurate lattice energy predictions with DFT+MBD energetics on top of vdW-inclusive DFTB3 structures, resulting in a speedup of up to 3000 times compared with a full DFT treatment. This suggests that vdW-inclusive DFTB3 can serve as a viable structural prescreening tool in crystal structure prediction.
在材料科学中，准确预测分子晶体的结构和稳定性至关重要，这需要对长程色散相互作用进行可靠的建模。半经验电子结构方法在计算上比从头算方法更高效，能够显著加速结构采样。我们通过一种基于电荷布居的方法，将特卡琴科 - 谢弗勒范德华方法（TS）和多体色散方法（MBD）与三阶密度泛函紧束缚方法（DFTB3）相结合。我们发现，尽管由于DFTB参数化导致晶体体积被低估，但对于分子晶体的X23基准数据库，整体表现良好。在包含范德华力的DFTB3结构之上，我们利用DFT + MBD能量学实现了准确的晶格能预测，与全DFT处理相比，加速倍数高达3000倍。这表明包含范德华力的DFTB3可作为晶体结构预测中一种可行的结构预筛选工具。
