Chemical reactions and charge-transfer processes in the system CO2 2+ + D2 were investigated in crossed-beam scattering experiments. Theoretical calculations of stationary points on the dication potential energy surface (CO2D2)2+ were carried out to complement the experiments. The main ion products identified were CO2D+, COD, CO2 +, CO+, and O+. The relative cross sections for reactions with D2 (H2) were in the ratio CO2 +:COD+:CO2D+ = 100:10:1 and were almost independent of the collision energy over the range 0.5−4 eV (center-of-mass, C.M.). The chemical product CO2D+ was formed in a nondissociative chemical reaction leading to CO2D+ + D+ through two channels that released different amounts of translational energy via decomposition of intermediates (CO2D2)2+; the high translational energy release channel (peak value at 4 eV) is consistent with the energetics of formation of a D−C-bonded isomer DCO2 +, which dissociates further to form DCO+ + O. The charge-transfer product CO2 + is formed prevailingly in the excited states A and B; a small amount is also formed by further dissociation of the product CO2D+ (formed in the low translational energy release channel, presumably in an excited state) to CO2 + + D. The product CO+ results from two different processes:  from charge transfer leading to CO2 +(C2Σg +) + D2 + and predissociation of the C state to CO+(X2Σ+) + O(3P) and from spontaneous dissociation of the projectile CO2 2+ (vibrationally excited to its predissociation barrier) to CO+ + O+.

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Energy transfer in ion−surface interactions between ethanol molecular ion and self-assembled monolayers formed by perfluoro-hydrocarbon (CF-SAM), hydrocarbon (CH-SAM), and hydrocarbon with terminal −COOH group (COOH-SAM) C11 or C12 chains were investigated over the incident energy range of 11−32 eV for several incident angles. Mass spectra and translational and angular distributions of product ions were used to determine distributions characterizing the partitioning of incident energy of the projectile ion into the internal excitation of the projectile, product ion translational energy, and energy absorbed by the surface. For the CF-SAM, the fraction of energy transformed into internal energy of the projectile had a maximum at about 17% of the projectile ion incident energy and did not depend on the incident angle between 40° and 80° (with respect to the surface normal); the fraction of energy in product translation was for the incident angle of 60° (measured at the product ion angular maximum) about 37%. For the CH-SAM and COOH-SAM and incident angle of 60°, the respective fractions were (peak values) 5−6% into internal excitation of the projectile, 27−30% into product translational energy, and about 64−68% absorbed by the surface, very similar as those for collisions with a hydrocarbon-covered stainless steel surface, investigated earlier.

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