화학공학소재연구정보센터
Journal of Chemical Physics, Vol.108, No.5, 2251-2260, 1998
Electron impact overtone excitation via the (2)Sigma(u) resonance in N-2 films physisorbed on Ag(110) at 15 K
The growth and structure of solid nitrogen films on Ag(110) at 15 K was investigated by means of high resolution electron energy loss spectroscopy (EELS), thermal desorption spectroscopy (TDS), and low energy electron diffraction (LEED). The N-2 film exhibits a parallelogram structure in the monolayer. For the bilayer and multilayers an incoherent hexagonal structure-has been found. The dynamics of the resonant vibrational excitation of the N-2 molecule via the (2) Sigma(u) resonance is studied in detail both by the EELS method (as a function of the surface coverage) and theoretically. This allows a discussion of the effect of the adsorption on the vibrational excitation process and, in particular, on the overtone excitation. The (2) Sigma(u) resonance excitation process is found to be almost not influenced by the adsorption in strong contrast with the case of the low energy ((IIg)-I-2) N-2 resonance. The differences between these two processes are discussed.