Analysis of Adsorbed Methane Gas Structure and Mullikan Charges

Abstract:

The methane molecule model, the coal molecule model and the absorption model of coal and methane have been thoroughly investigated using the DFT method,Van der Walls force radius as boundary conditions as well. The investigations focuses on optimizing the three types of model structure. Meanwhile, adsorption equilibrium geometries with 6-311G++ basic sets have been established. Through the model analysis of the changes in the structure and Millikan charge from free state to the adsorption states, the results indicate that the adsorption process of methane gas on the coal in the Van der Walls force mainly dispersion forces and induction force, methane molecules are polarized in the adsorption process, the electric dipole moment.

• Periodical: Advanced Materials Research (Volumes 962-965)
• Pages: 1118-1122
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.962-965.1118
• Online since: June 2014
• Authors: Hua Ping Yang, Ming Li
• Keywords: Absorption, Density Function Theory, Mullikan Atomic Charges

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