Phase transition of nitrogen adsorbed on benzene-preplated graphite at 77 K

Abstract Volumetric adsorption isotherms of nitrogen have been measured on Grafoil preplated with various amounts of benzene at 77 K. Preplated benzene as small as ~ 1 4 monolayer prevents post-adsorbed nitrogen from undergoing the fluid-solid phase transition on the graphite basal plane. When more benzene is preplated, a new step appears on the isotherm at higher pressures. The new step is assigned to a phase transition of nitrogen adsorbed onto a monolayer or single-layer islands of benzene.