Abstract
The physical adsorption of molecules (C2H2, C2H4, C2H6, C6H6, CH4, H2, H2O, N2, NH3, CO, CO2, Ar) on a graphite substrate has been investigated at the DFT/CC level of theory. The calculated DFT/CC interaction energies were compared with the available experimental data at the zero coverage limit.
The differences between the DFT/CC results and experiment are within a few tenths of kJ mol(-1) for the most accurate experimental estimates (Ar, H2, N2, CH4) and within 1-2 kJ mol(-1) for the other systems (C2H2, C2H4, C2H6, C6H6, CO, CO2). For water-graphite and ammonia-graphite complexes, DFT/CC predicts interaction energies of 13 kJ mol(-1) in good accord with the DF-DFT-SAPT and DFT-D calculations.
The relevance of the results obtained with the coronene model for the description of the physisorption on graphite surface was also studied.