Communication: Accurate higher-order van der Waals coefficients between molecules from a model dynamic multipole polarizability
Abstract
Due to the absence of the long-range van der Waals (vdW) interaction, conventional density functional theory (DFT) often fails in the description of molecular complexes and solids. In recent years, considerable progress has been made in the development of the vdW correction. However, the vdW correction based on the leading-order coefficient C6 alone can only achieve limited accuracy, while accurate modeling of higher-order coefficients remains a formidable task, due to the strong non-additivity effect. Here, we apply a model dynamic multipole polarizability within a modified single-frequency approximation to calculate C8 and C10 between small molecules. We find that the higher-order vdW coefficients from this model can achieve remarkable accuracy, with mean absolute relative deviations of 5% for C8 and 7% for C10. Inclusion of accurate higher-order contributions in the vdW correction will effectively enhance the predictive power of DFT in condensed matter physics and quantum chemistry.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 20, 2016
- Source ID
- 10.1063/1.4940397
Entities
People
- Andrew M Rappe
- Jianmin Tao
Organizations
- National Science Foundation
- Office of Naval Research
- Temple University
- United States Department of Energy
- University of Pennsylvania