Steering and ro-vibrational effects in the dissociative adsorption and associative desorption of H_2/Pd(100)

TL;DR

This study uses six-dimensional quantum dynamical calculations to reveal how steering effects and ro-vibrational couplings influence hydrogen dissociation and recombination on Pd(100) surfaces, highlighting the complex interplay of molecular degrees of freedom.

Contribution

It introduces a detailed quantum dynamical approach to analyze the impact of steering and ro-vibrational effects in H_2/Pd(100) reactions, based on ab initio potential energy surfaces.

Findings

Strong steering effects influence dissociative adsorption and desorption.

Coupling of translational, rotational, and vibrational degrees affects reaction dynamics.

Broad distribution of barrier heights leads to diverse reaction pathways.

Abstract

The interaction of hydrogen with many transition metal surfaces is characterized by a coexistence of activated with non-activated paths to adsorption with a broad distribution of barrier heights. By performing six-dimensional quantum dynamical calculations using a potential energy surface derived from ab initio calculations for the system H_2/Pd(100) we show that these features of the potential energy surface lead to strong steering effects in the dissociative adsorption and associative desorption dynamics. In particular, we focus on the coupling of the translational, rotational and vibrational degrees of freedom of the hydrogen molecule in the reaction dynamics.