Determination of the electron’s solvation site on D2O/Cu(111) using Xe overlayers and femtosecond photoelectron spectroscopy

Abstract

We investigate the binding site of solvated electrons in amorphous D(2)O clusters and D(2)O wetting layers adsorbed on Cu(111) by means of two-photon photoelectron (2PPE) spectroscopy. On the basis of different interactions of bulk- or surface-bound solvated electrons with rare gas atoms, titration experiments using Xe overlayers reveal the location of the electron solvation sites. In the case of flat clusters with a height of 2-4 bilayers adsorbed on Cu(111), solvated electrons are found to reside at the ice-vacuum interface, whereas a bulk character is found for solvated electrons in wetting layers. Furthermore, time-resolved experiments are performed to determine the origin of the transition between these different solvation sites with increasing D(2)O coverage. We employ an empirical model calculation to analyse the rate of electron transfer back to the substrate and the energetic stabilization of the solvated electrons, which allows further insight into the binding site for clusters. We find that the solvated electrons reside at the edges of the clusters. Therefore, we attribute the transition from surface- to bulk-solvation to the coalescence of the clusters to a closed ice film occurring at a nominal coverage of 2-3 BL, while the distance of the binding sites to the metal-ice interface is maintained.

Cosmic-ray-driven electron-induced reactions of halogenated molecules adsorbed on ice surfaces: Implications for atmospheric ozone depletion and global climate change

“…In 2000s, Researches on electron solvation dynamics and associated dissociative electron transfer reactions of halogenated molecules have continued in water solution [21,[27][28][29][58][59][60][61][62], ice surface [63], ultrathin ice films [16,17,[64][65][66][67] and H 2 O anionic clusters [68][69][70][71][72][73]. Prior to 2008, many experimental and theoretical studies gave very diverse lifetimes and physical natures of e pre states in liquid water [49][50][51][52][53][54][58][59][60][61][62].…”

Real-Time Measurement of the Vertical Binding Energy during the Birth of a Solvated Electron

“…21,23 These SEs are localized in the second−third ice bilayer (BL) in front of the metal template. 22 Despite these previous studies, (i) the VBE of the ice CB, (ii) …”

Interaction of H2O and H2S with Cu(111) and the impact of the electric field: the rotating & translating adsorbate, and the rippled surface

“…Although its contribution is small, the presence of the water molecules in the neighboring adsorption sites (e.g., a water bilayer structure which takes a hexagonal arrangement 35 ) interrupts the rippled pattern which may reduce the adsorption strength of the water molecule. This may contribute to the hydrophobic nature of Cu(111) surface where the water does not form a bilayer structure but instead forms 3D clusters 2,45,46 . However, further investigation is needed to determine the impact of the rippled surface on the wettability of the surface.…”