Surface-induced dissociation of H₃⁺ and C₄H₁₀⁺ on Pt(111) and CH⁺ on Cu(111)

Abstract

The interaction of 6 keV CH+ with a Cu(111) surface and 3 keV H3+ and 2.3 keV C4H10+ with a Pt(111) surface under glancing incidence conditions (surface normal energies of 0.7 eV and 4 eV) is examined. In this geometry, the contribution of the direct "collision induced" dissociation mechanisms is minimal. We find strong evidence for direct dissociation of H3+ via charge capture to the dissociative 2p, 2E′ ground state. The surface-induced dissociation of CH+ and C4H10+ appears to proceed via two steps, namely charge capture to a bound state of the neutral molecule, followed by the transfer of translational energy into a vibrational co-ordinate of the molecule. We propose that this T-V energy transfer occurs via repeated inelastic electron scattering events. \ua9 1998 Elsevier Science B.V