Molecular Dynamics of Gas-Surface Interactions

Molecular dynamics simulations of gas–surface interactions encompass the detailed study of how individual gas-phase atoms or molecules approach, scatter from, adsorb onto and react with solid surfaces. These processes underpin applications ranging from heterogeneous catalysis and sensor technology to advanced coatings and thin‐film deposition. At their core, simulations track the trajectories of gas‐phase species over atomically resolved potential energy surfaces (PES), capturing how translational, rotational and vibrational energy is exchanged with surface phonons, electronic degrees of freedom or adsorbate states. Advances in both first‐principles methods and machine‐learned interatomic potentials have extended the accessible time and length scales, allowing researchers to probe ultrafast processes such as direct reactive scattering, thermal accommodation and nonadiabatic energy dissipation.

Key developments include the full‐dimensional quantum treatment of polyatomic dissociative chemisorption, which reveals how specific vibrational modes of a molecule can dramatically enhance or inhibit reaction probabilities. At metal surfaces, nonadiabatic mechanisms—where electrons and nuclei exchange energy on comparable time scales—affect both sticking probabilities and energy disposal in the product species. Classical and semiclassical trajectory methods, often bolstered by density functional theory, permit mapping of reactive trajectories and offer mechanistic insight into transition‐state character, enabling the rational design of catalysts with tailored activity and selectivity.

On the experimental front, neutral atom scattering techniques such as helium atom diffraction and microscopy provide direct imaging and diffraction contrast that are uniquely surface sensitive. By combining these probes with advanced scattering models, it has become possible to extract quantitative topographical and structural information at the ångström scale without damaging delicate or insulating samples. The interplay of experiment and simulation continues to sharpen our understanding of gas‐surface dynamics, informing fields as diverse as plasma catalysis, tribology and environmental chemistry.

Research from Nature Portfolio

Recent studies have demonstrated sub‐resolution contrast in neutral helium microscopy through advanced facet‐scattering models. By fitting simulated scattering intensities to experimental images, researchers have quantified local variations in surface corrugation at the ångström level, enabling non‐destructive nanoscale imaging of thin films and adsorbate layers across centimetre‐scale samples.

In a pioneering quantum dynamics investigation, all nine degrees of freedom of water dissociating on a rigid copper surface were coupled on an accurate PES. This work revealed that vibrational excitations in the asymmetric stretch mode promote dissociative chemisorption more effectively than increased translational energy, and provided a benchmark for reduced‐dimensional models by comparing seven‐dimensional averages to full‐dimensional results.

Another breakthrough introduced magnetic manipulation of molecular rotational states to control and resolve orientation in H₂–surface collisions. This approach enabled direct comparison of stereodynamic scattering from flat and stepped metal surfaces, showing marked differences in interaction corrugation and opening routes to quantum‐state‐resolved interferometry for surface science applications.

Molecular Dynamics of Gas-Surface Interactions publication trend

The graph below shows the total number of articles in molecular dynamics of gas-surface interactions across all publications each year (not limited to Nature Index journals).

Technical terms

Molecular dynamics (MD): A computational technique that simulates trajectories of atoms and molecules over time by solving Newton’s equations of motion on an interatomic potential.

Potential energy surface (PES): A multidimensional hypersurface representing the energy of a system as a function of atomic positions, dictating the forces acting on the particles.

Chemisorption: The process by which a gas‐phase species forms a chemical bond with a surface, often accompanied by energy dissipation and electronic rearrangement.

Nonadiabatic dynamics: Interactions in which electronic and nuclear motions occur on comparable time scales, leading to energy exchange beyond classical phonon coupling.

Eley–Rideal mechanism: A reaction pathway in which a gas‐phase atom directly reacts with an adsorbed species on the surface without first thermalising.

Electronic friction: A model describing dissipative forces on adsorbates due to the excitation of electron–hole pairs in a metal surface during dynamical processes.

References

1. Sub-resolution contrast in neutral helium microscopy through facet scattering for quantitative imaging of nanoscale topographies on macroscopic surfaces. Nature Communications (2023).
2. First-principles quantum dynamical theory for the dissociative chemisorption of H2O on rigid Cu(111). Nature Communications (2016).
3. A seven-dimensional quantum dynamics study of the dissociative chemisorption of H 2 O on Cu(111): effects of azimuthal angles and azimuthal angle-averaging. Chemical Science (2016).
4. A general method for controlling and resolving rotational orientation of molecules in molecule-surface collisions. Nature Communications (2017).
5. Highly Rotationally Excited N2 Reveals Transition-State Character in the Thermal Decomposition of N2O on Pd(110). Journal of the American Chemical Society (2023).
6. Energy transfer during hydrogen atom collisions with surfaces. Trends in Chemistry (2023).
7. Understanding the Photoinduced Desorption and Oxidation of CO on Ru(0001) Using a Neural Network Potential Energy Surface. JACS Au (2024).