Time distributions of neutral molecules desorbed from a chemisorbed self-assembled monolayer of phenylethanethiol on gold have been measured subsequent to 8 keV Ar + and H 2 + ion bombardment. These distributions show that, regardless of the projectile used, most of the ejected molecules leave the surface with thermal kinetic energies (∼0.03 eV). The shapes of the distributions have a strong surface temperature dependence over the range 240-300 K. This behavior is well described by a convolution of the Maxwell-Boltzmann distribution and the rate equation for first-order desorption. The results imply that kiloelectronvolt ion bombardment initiates a process which breaks the adsorbate-surface bond, leaving the resulting physisorbed molecules to evaporate after attaining thermal equilibrium with the substrate. A mechanism for this gentle cleavage of the adsorbate-substrate bond is proposed.

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Kinetic energy distributions of Ni atoms in six electronic fine structure states ejected from a single crystal Ni{001} surface due to bombardment with 5 keV Ar 1 ions have been measured. These states arise from two different electronic configurations, 3d 8 4s 2 ͕a 3 F 4,3,2 ͖ and 3d 9 4s 1 ͕a 3 D 3,2 or a 1 D 2 ͖, which form three distinct fine structure manifolds within 0.422 eV of the 3 F 4 ground state. We find that the band structure effects dominate leading to larger populations in the excited 3 D 3,2 states than found for the ground state.

The solubility of amorphous sodium aluminosilicate solid and zeolite A crystals in sodium hydroxide and nitrated/nitrited sodium aluminate solutions has been determined at temperatures of (303.15, 338.15, and 403.15) K and as a function of solution NaOH, NaNO3, NaNO2, and Al(III) concentrations. Similar solubilities were measured when equilibrium was approached from below (via dissolution in undersaturated liquor) and above (by precipitation from supersaturated liquors). The solubility (expressed in terms of SiO2 and Al(III) concentrations) increased monotonically with increasing temperature, solution ionic strength, and hydroxide concentration for both amorphous and zeolite A phases. However, the solubility decreased with increasing solution Al(III), NO3 -, and NO2 - concentrations and was significantly higher for the amorphous than the zeolite phase at all temperatures and solution conditions.