Failure of Conventional Density Functionals for the Prediction of Molecular Crystal Polymorphism: A Quantum Monte Carlo Study
Failure of Conventional Density Functionals for the Prediction of Molecular Crystal Polymorphism: A Quantum Monte Carlo Study
复制标题
DOI：
10.1021/jz100418p
复制
发表时间：
2010-06-17
影响因子：
5.7
通讯作者：
Aspuru-Guzik, Alan
中科院分区：
文献类型：
--
作者：
Hongo, Kenta;Watson, Mark A.;Aspuru-Guzik, Alan
我们首次将扩散蒙特卡罗方法应用于有机分子晶体（对二碘苯），以确定其两种众所周知的多晶型物的相对稳定性。 DMC 结果预测，在零温度下，α 相比 β 相更稳定，与比较实验一致，我们评估了四种常用的局部半局域和混合密度泛函，包括包括色散影响的经验校正。我们的结论是，虽然密度泛函理论可能提供估计电子关联效应的最实用的方法，但不能准确描述非共价相互作用的常规泛函对于确定此类系统中的高精度能量可能不被认为是可靠的。
We have applied the diffusion Monte Carlo method for the first time, to an organic molecular crystal (para-diiodobenzene) in order to determine the relative stability of its two well-known polymorphs. The DMC result predicts that the alpha phase is more stable than the beta phase at zero temperature, in agreement with experiment in comparison, we evaluated four commonly used local semilocal, and hybrid density functionals including an empirical correction to include the effects of dispersion. We conclude that while density functional theory may provide the most practical method for estimating the effects of electron correlation, conventional functionals which do not accurately describe nonconvalent interations may not be considered reliable for determining highly accurate energies in such systems.