Abstract：Adopting the critical gas parameter method confirming methane molecular potential, molecular potential function of methane in distance of three times methane molecules was calculated. Combining the absorption model of a positive triangle cone, an inverted triangle cone and coal surface barrier, and using the theory of quantum mechanics, and considering classical mechanics characteristic of methane molecules under extreme conditions, it established wave equation of methane mdecules absorption potential action on the coal surface. At the same time, considering although methane molecules uninterrupted adsorption and desorption on coal surface and single molecule movement influenced by time, the total amount of adsorption of methane were independent of time. Thusly, the time and distance were independent variables and gave the solution of equation under the certain circumstances. This research lays a theoretical foundation for the study of action between coal surface and methane molecules.

Keyword：methane molecules;interaction potential;molecular dynamics;coal surface;