Acidity of Hydrogen Chloride on Ice

Reactive Ion Scattering of Low Energy Cs+from Surfaces. A Technique for Surface Molecular Analysis

“…[4][5][6] However, in the later experiments, much higher (up to ~1) RIS yields were observed for small molecules physisorbed on surfaces, such as CO 2 , H2O, and noble gases on metal surfaces [51][52][53] and frozen water films. 8,[12][13][14][15]32 The early two-step mechanism cannot explain the high RIS yields observed in these experiments. Studies using classical molecular dynamics simulations [48][49][50] support the idea that the RIS process actually occurs via a one-step abstraction mechanism, which is categorized as an Eley-Rideal (ER) type surface reaction.…”

“…[2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] In general, RIS refers to a variety of ion scattering experiments that exploit reactive processes taking place between active projectile ions and surfaces. The reactive processes include ion-surface charge exchange, the dissociation of molecular projectiles, transfer of an atom or functional moiety between a projectile ion and a surface, etc.…”

“…The RIS phenomenon was discovered first on a Si surface onto which water molecules had been adsorbed, where Cs + projectile ions scattering from the surface picked up water molecules to form Cs + -water complexes. 2 Since then, the RIS process has been examined on various surfaces and molecular adsorbate systems, [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] and the RIS mechanism has been investigated theoretically by using molecular dynamics simulations. [48][49][50][51][52][53] These studies indicate that the nature of the RIS process is quite universal and, therefore, it can be applied to the analysis of molecules on surfaces.…”

“…This type of process can occur for systems such as alkali metal ions on a high work-function surface 63 and electrolyte ions that are stabilized by water solvation on an ice surface. 8,[12][13][14][15]32 The collisional desorption of preexisting ions, called the low energy sputtering (LES), has been investigated in the author's group on various ion-containing surfaces. 8,[12][13][14][15]32,63 Figure 6 shows the result of LES study for hydronium ( (m/z = 133), while the LES signals for small ions appear at low masses.…”

The Influence of HCl on the Evaporation Rates of H2O over Water Ice in the Range 188 to 210 K at small Average Concentrations

“…Most recent results seem to point towards the existence of molecularly adsorbed HCl on ice below 50 K and at submonolayer coverages in coexistence with ionized solvated HCl whose fraction increases with increasing ice temperature Delzeit et al, 1993a;Delzeit et al 1997;Uras et al, 1998;Devlin et al, 2002;Lu and Sanche, 2001). Kang et al discovered that both molecularly adsorbed as well as ionized HCl coexisted on ice that was deposited under Ultra-High Vacuum (UHV) conditions in the temperature range 50 to 140 K and under conditions of low HCl exposure (Kang et al, 2000).…”