Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (08): 1809-1814.doi: 10.3866/PKU.WHXB201205242

• THERMODYNAMICS, KINETICS, AND STRUCTURAL CHEMISTRY • Previous Articles     Next Articles

Lattice Energies and Elastic Properties of Solid Methane: Assessment of Different Density Functionals

ZHENG Zhao-Yang, ZHAO Ji-Jun   

  1. School of Physics and Optoelectronic Technology, College of Advanced Science and Technology, Dalian University of Technology, Dalian 116024, P. R. China
  • Received:2012-03-26 Revised:2012-05-23 Published:2012-07-10
  • Contact: ZHAO Ji-Jun E-mail:zhaojj@dlut.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (11174045) and Fundamental Research Funds for the Central Universities of China (DUT12YQ05).

Abstract:

The performance of density functional theory (DFT) with and without dispersion energy correction for describing van der Waals (vdW) systems is evaluated by calculating the crystal structure, lattice energy, and elastic properties of solid methane. The results obtained from DFT with different exchange-correlation functionals (including some hybrid functionals) and from DFT with dispersion energy correction (DFT-D) methods are compared with experimental values. Although the DFT-D methods typically perform better than the standard and hybrid DFT functionals, some of them overcorrect the vdW interaction in solid methane. Thus, one must be cautious when using DFT-D methods.

Key words: First-principles, Molecular crystal, van der Waals interaction, Lattice energy, Solid methane