Layering, freezing transitions, capillary condensation and diffusion of methane in slit carbon pores

Abstract

Grand canonical Monte Carlo and molecular dynamics simulation methods have been used to study layering transitions, freezing transitions, capillary condensation and adsorption hysteresis for a simple model of methane confined in slit carbon micropores at temperatures between 60 K and 135 K and for pore widths from 19 Å to 76 Å. The grand potentials of the systems were calculated and the thermodynamic phase transitions between the two branches of the isotherms were found. The mobility of molecules perpendicular to the pore walls and the diffusion coefficient parallel to the pore walls were calculated for layers near the wall.