Institute of Pharmaceutical Innovation, University of Bradford, Bradford, West Yorkshire, BD7 1DP, United Kingdom.
J Phys Chem B. 2009 Dec 24;113(51):16303-13. doi: 10.1021/jp906971h.
In the 2007 blind test of crystal structure prediction hosted by the Cambridge Crystallographic Data Centre (CCDC), a hybrid DFT/MM method correctly ranked each of the four experimental structures as having the lowest lattice energy of all the crystal structures predicted for each molecule. The work presented here further validates this hybrid method by optimizing the crystal structures (experimental and submitted) of the first three CCDC blind tests held in 1999, 2001, and 2004. Except for the crystal structures of compound IX, all structures were reminimized and ranked according to their lattice energies. The hybrid method computes the lattice energy of a crystal structure as the sum of the DFT total energy and a van der Waals (dispersion) energy correction. Considering all four blind tests, the crystal structure with the lowest lattice energy corresponds to the experimentally observed structure for 12 out of 14 molecules. Moreover, good geometrical agreement is observed between the structures determined by the hybrid method and those measured experimentally. In comparison with the correct submissions made by the blind test participants, all hybrid optimized crystal structures (apart from compound II) have the smallest calculated root mean squared deviations from the experimentally observed structures. It is predicted that a new polymorph of compound V exists under pressure.
在 2007 年由剑桥晶体数据中心 (CCDC) 主办的晶体结构预测盲测中，一种混合 DFT/MM 方法正确地将每个实验结构排列为每个分子预测的晶体结构中晶格能最低的结构。本文通过优化 1999 年、2001 年和 2004 年举办的前三届 CCDC 盲测中提交的实验和提交的晶体结构，进一步验证了这种混合方法。除了化合物 IX 的晶体结构外，所有结构都根据晶格能进行了重新最小化和排序。混合方法将晶体结构的晶格能计算为 DFT 总能量和范德华（色散）能量校正的总和。考虑到所有四个盲测，在 14 个分子中，有 12 个分子的晶体结构的晶格能最低，对应于实验观察到的结构。此外，通过混合方法确定的结构与实验测量的结构之间观察到了良好的几何一致性。与盲测参与者提交的正确结果相比，所有混合优化的晶体结构（化合物 II 除外）与实验观察到的结构的计算均方根偏差最小。预测化合物 V 在压力下存在新的多晶型物。
