## Files in this item

FilesDescriptionFormat

application/pdf

2268.pdf (19kB)
(no description provided)PDF

## Description

 Title: ROTATIONALLY-RESOLVED SCATTERING OF FORMALDEHYDE FROM THE Au(111) SURFACE: AN AXIS SPECIFIC ROTATIONAL RAINBOW AND ITS ROLE IN TRAPPING PROBABILITY Author(s): Park, Barratt Contributor(s): Schaefer, Tim; Wodtke, Alec; Kandratsenka, Alexander; Meyer, Sven; Krueger, Bastian C. Subject(s): Dynamics and kinetics Abstract: The conversion of translational to rotational motion often plays a major role in the trapping of small molecules at surfaces, a crucial first step for a wide variety of chemical processes that occur at gas-surface interfaces. However, to date most quantum-state resolved surface scattering experiments have been performed on diatomic molecules, and very little detailed information is available about how the structure of non-linear polyatomic molecules influences the mechanisms for energy exchange with surfaces. In the current work, we employ a new rotationally-resolved $1+1'$ resonance-enhanced multiphoton ionization (REMPI) scheme to measure rotational distribution in formaldehyde molecules directly scattered from the Au(111) surface at incident kinetic energies in the range 0.3--1.2 eV. The results indicate a pronounced propensity to excite $a$-axis rotation (twirling) rather than $b$- or $c$-axis rotation (tumbling or cartwheeling), and are consistent with a rotational rainbow scattering model. Classical trajectory calculations suggest that the effect arises---to zeroth order---from the three-dimensional shape of the molecule (steric effects). The results have broad implications for the enhanced trapping probability of prolate and near-prolate molecules at surfaces. Issue Date: 6/21/2017 Publisher: International Symposium on Molecular Spectroscopy Citation Info: APS Genre: CONFERENCE PAPER/PRESENTATION Type: Text Language: English URI: http://hdl.handle.net/2142/96889 DOI: 10.15278/isms.2017.WH07 Date Available in IDEALS: 2017-07-27
﻿