苯二聚体的密度泛函和分子力场的理论研究

Assessment of Some Density Functional Theory Methods and Force Field Models in Describing Various Interaction Modes of Benzene Dimer

针对苯二聚体中的六种重要构象的相互作用，对四种新的密度泛函方法（B97-D、BLYP—D3、M06—2X、XYG3）和常用的分子力场（CHARMM、AMBER、MM3、AMOEBA）进行了系统的评测．研究结果不仅突出了这些新型密度泛函方法，特别是XYG3泛函在描述一相互作用体系的实用性，同时也为进一步发展适合描述相互作用体系的分子力场奠定了基础．

Benzene dimer （bz2） is the simplest prototype of the π-π interactions. Such interactions are ubiquitous in diverse areas of science and molecular engineering. In the present work, we have made assessment on some modern density functional methods including B97-D, BLYP-D3, M06-2X, XYG3, and force field models including CHARMM, AMBER, MM3, AMOEBA on six important interaction modes of bz2. Our results not only highlight the usefulness of these cost-effective methods, which can be used as economic substitutes of the expensive CCSD（T） for complex real-world systems, but also indicate their weakness in the description of the π-π interactions, which points to the future direction for further improvements.