Study of surface-molecule interactions using nuclear resonance photon scattering

Nuclear resonance photon scattering from the 6324-keV level in ¹⁵N was used for studying the surface-molecule interaction of nitrogen (N₂) on graphite. Other N-containing gaseous molecules (such as NO and N₂O) and other surfaces such that of activated carbon fiber (ACF) were also used. In particular, the average zero point energies of the out-of-plane vibrational and librational potentials of the molecules with respect to the adsorbing surfaces were determined. In addition, the out-of-plane orientation of the molecules versus T and as a function of the coverage were measured. In the nitrogen-graphite system, the results were used for testing the calculated in-plane and out of plane phonon spectra and for testing calculations of molecular dynamic simulations.