The deconvolution of the Ar scattering data into TD and IS components was accomplished by fitting the slow component of the TOF distribution with a MB distribution and then subtracting this distribution from the overall TOF distribution to obtain the IS distribution . A MB distribution fit the slow components of the TOF distributions remarkably well, as exemplified in the deconvoluted TOF distribution shown in Figure . Translational energy distributions, P(ET), of the IS and TD Ar atoms were derived from the TOF distributions, and the integral of a given P(ET) distribution is proportional to total relative flux of the atoms that scatter at a particular θf. An example of the P(ET) distributions corresponding to IS and TD Ar atoms is shown in Figure , and the integrated fluxes of the IS and TD Ar atoms as a function of sample temperature are shown in Figure . In order to obtain the integrated fluxes of the IS component, the integration was restricted to a lower final energy (〈Ef〉) limit of 2RTs, and the upper limit of 〈Ef〉 was restricted to the average energy of the incident Ar atoms, 〈Ei〉.