AVS 52nd International Symposium
    Surface Science Thursday Sessions
       Session SS2-ThA

Invited Paper SS2-ThA3
Molecular Beam Studies of Rare Gas and HCl Collisions with Functionalized Self-Assembled Monolayers

Thursday, November 3, 2005, 2:40 pm, Room 203

Session: Gas-Surface Reaction Dynamics
Presenter: J.R. Morris, Virginia Tech
Authors: B.S. Day, Virginia Tech
L.R. Fiegland, Virginia Tech
J.R. Morris, Virginia Tech
Correspondent: Click to Email
The research objectives of this work are aimed at elucidating the atomic-scale mechanisms of interfacial bonding, diffusion, and reactions that govern gas-surface interactions on organic surfaces. This challenge is particularly formidable for functionalized organic surfaces where the complicated nature of the interface can result in a broad range of reaction pathways. The approach used in these studies for exploring gas-surface reaction mechanisms combines molecular beam scattering techniques with functionalized self-assembled monolayers. Together with surface analysis instrumentation, these techniques are designed to reveal insight into many aspects of the gas-surface interaction and help develop an atomic-level description of the transformation of reactants into products. This presentation will focus on recent investigations into the dynamics of rare gas and HCl collisions with self-assembled monolayers. Atomic beams of high-energy rare gases are employed to explore the initial gas-surface collision in the absence of reactivity. These studies reveal how the atomic-scale nature of organic surfaces determine the extent of interfacial energy transfer and the path to thermal accommodation. The atom scattering studies are used to help interpret the dynamics of reactive gas-surface collisions, such as HCl impinging on a hydroxylated surface. In this work, HCl is directed at OH-terminated self-assembled monolayers to learn about how gas-surface hydrogen-bonding forces influence the dynamics of the collision. Measurements of the HCl energy transfer, residence time, and proton exchange probability have provided new insight into the interactions of HCl with well-characterized hydroxylated surfaces.