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This editorial discusses the importance of understanding energy dissipation and physicochemical processes at the atomic and molecular level on surfaces. The article highlights the significance of these processes in various fields such as catalysis, materials science, and nanotechnology. The editorial presents a collection of 11 articles that explore different aspects of surface dynamics, including molecular motion, water-surface interactions, electron-phonon coupling, and photoinduced reactions. The research utilizes experimental and theoretical methods to gain insights into these processes and their potential applications in areas like hydrogen production and optoelectronics. While challenges remain, further research in this field has the potential to revolutionize material fabrication and device control. [Extracted from the article]

Mass transport at surfaces determines the kinetics of processes such as heterogeneous catalysis and thin-film growth, with the diffusivity being controlled by excitation across a translational barrier. Here, we use neutron spectroscopy to follow the nanoscopic motion of triphenylphosphine (P(C 6 H 5 ) 3 or PPh 3 ) adsorbed on exfoliated graphite. Together with force-field molecular dynamics simulations, we show that the motion is similar to that of a molecular motor, i.e. PPh 3 rolls over the surface with an almost negligible activation energy for rotations and motion of the phenyl groups and a comparably small activation energy for translation. While rotations and intramolecular motion dominate up to about 300 K, the molecules follow an additional translational jump-motion across the surface from 350-500 K. The unique behaviour of PPh 3 is due to its three-point binding with the surface: Along with van der Waals corrected density functional theory calculations, we illustrate that the adsorption energy of PPh 3 increases considerably compared to molecules with flat adsorption geometry, yet the effective diffusion barrier for translational motion increases only slightly. We rationalise these results in terms of molecular symmetry, structure and contact angle, illustrating that the molecular degrees of freedom in larger molecules are intimately connected with the diffusivity., (© 2024. The Author(s).)