NO thermally desorbed from a saturation coverage on Pt(111): Internal state distributions

Abstract

Internal state distributions were obtained by laser-excited fluorescence for NO desorbing from a saturation coverage on Pt(111). Two major peaks are observed in the thermal desorption spectrum at crystal temperatures Ts=200 and 340 K. The rotational state distributions for each desorption feature were Boltzmann, described by the rotational temperatures TR=195±10 K and 305±10 K, respectively. The two spin-orbit states were occupied to a degree consistent with equilibration between spin and rotational degrees of freedom, both Lambda doublet species were statistically populated and no molecular alignment was observed.