Ready, set and no action: A static perspective on potential energy surfaces commonly used in gas-surface dynamics

TL;DR

This paper reviews and compares advanced first-principle modeling approaches for potential energy surfaces in gas-surface dynamics, highlighting their complexities, limitations, and implications for accurately describing molecular interactions with metal surfaces.

Contribution

It provides a comparative analysis of two high-dimensional PES representation methods using DFT data for O2-Ag(100), revealing their strengths and deficiencies in static evaluations.

Findings

Different PES representations exhibit unique deficiencies affecting dynamical predictions.

The study highlights the importance of comprehensive PES evaluation beyond local minima.

Representation inaccuracies can significantly influence gas-surface reaction dynamics.

Abstract

In honoring the seminal contribution of Henry Eyring and Michael Polanyi who first introduced the concept of potential energy surfaces (PESs) to describe chemical reactions in gas-phase [Z. Phys. Chem. 12, 279-311, (1931)], this work comes to review and assess state-of-the-art approaches towards first-principle based modeling in the field of gas-surface dynamics. Within the Born-Oppenheimer and frozen surface approximations, the O2-Ag(100) interaction energetics are used as a showcase system to accentuate the complex landscape exhibited by the PESs employed to describe the impingement of diatomics on metal substrates and draw attention to the far-from-trivial task of continuously representing them within all six molecular degrees of freedom. To this end, the same set of ab initio reference data obtained within Density Functional Theory (DFT) are continuously represented by two different state-of-the-art high-dimensional approaches, namely the Corrugation-Reducing Procedure and Neural Networks. Exploiting the numerically undemanding nature of the resulting representations, a detailed static evaluation is performed on both PESs based on an extensive global minima search. The latter proved particularly illuminating in revealing representation deficiencies which affect the dynamical picture yet go otherwise unnoticed within the so-called "divide-and-conquer" approach.