TRANSLATIONAL AND VIBRATIONAL-ENERGY RELEASE IN NITROGEN RECOMBINATIVE DESOPRTION FROM CU(111)

Nitrogen recombinative desorption from Cu(111) has been investigated u sing resonance enhanced multiphoton ionisation and ion time of flight measurements to obtain the release into N-2 product vibrational and tr anslational excitation. N-2(v = 0) desorbs from a 700K surface with a mean translational energy perpendicular to the surface of 4.2 eV, a su bstantial fraction of the N-2 bond strength. The desorbed molecules an vibrationally hot, with a population ratio P(v = 1)/P(v = 0) = 0.52, corresponding to a vibrational temperature of 5100 K, Md N-2(v = 1) sh ows a slightly lower translational energy release than the ground stat e. (C) 1997 Elsevier Science B.V.