Abstract
We report measurements of translational energy distributions when scattering NO(vi = 3, Ji = 1.5) from a Au(111) surface into vibrational states vf = 1, 2, 3 and rotational states up to Jf = 32.5 for various incidence energies ranging from 0.11 eV to 0.98 eV. We observed that the vibration-to-translation as well as the translation-to-rotation coupling depend on translational incidence energy, EI. The vibration-to-translation coupling, i.e. the additional recoil energy observed for vibrationally inelastic (v = 3 → 2, 1) scattering, is seen to increase with increasing EI. The final translational energy decreases approximately linearly with increasing rotational excitation. At incidence energies EI > 0.5 eV, the slopes of these dependencies are constant and identical for the three vibrational channels. At lower incidence energies, the slopes gradually approach zero for the vibrationally elastic channel while they exhibit more abrupt transitions for the vibrationally inelastic channels. We discuss possible mechanisms for both effects within the context of nonadiabatic electron-hole pair mediated energy transfer and orientation effects.
Highlights
Great strides in our understanding of surface chemistry have been made over the last two decades due to constantly improving computational methods that rely on the Born–Oppenheimer approximation[1] and exploit the power of modern electronic structure theory, especially density functional theory
First we will discuss the mechanical excitation of the solid, before we focus on the vibrational-to-translation energy transfer and afterwards on the dependence of final translation on the amount of rotational excitation for vibrationally elastic and inelastic scattering
In the limit of rotationally elastic collisions we find that the vibration-to-translation energy transfer, DhEf,v=1,2i À DhEf,v=3i, increases with increasing incidence energy
Summary
Great strides in our understanding of surface chemistry have been made over the last two decades due to constantly improving computational methods that rely on the Born–Oppenheimer (electronically adiabatic) approximation[1] and exploit the power of modern electronic structure theory, especially density functional theory. Despite this progress, describing and understanding the atomic-scale motion involved in surface reactions remains a daunting challenge. A central difficulty derives from our lack of understanding of energy exchange between an adsorbate and elementary excitations of the solid.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
