Speaker: George Trenins, Max Planck Institute for the Structure and Dynamics of Matter

Electronically nonadiabatic interactions open a key energy dissipation channel for dynamics on conducting surfaces. An established perturbative formulation enables practical simulations of the resulting dissipative dynamics using ab initio ``electronic friction'' (EF), computed from electron-phonon coupling matrix elements. Currently, such simulations almost exclusively treat atomic nuclei classically. To account for nuclear zero-point energy (ZPE) and tunnelling, we combine EF with ring-polymer molecular dynamics (RPMD): an imaginary-time path integral method that captures these effects at the cost of a molecular dynamics simulation in an extended phase-space. Our formulation encompasses spatially-dependent friction and accounts for non-Markovian (memory) effects. Memory plays a major role in the surface diffusion of hydrogen on Cu(111), effectively masking the rate enhancement due to ZPE. Using RPMD+EF, we can explain the anomalous agreement of classical simulations with experiment and open the way to accurate modelling of nonadiabatic interfacial dynamics. [G. Trenins and M. Rossi, Phys. Rev. Lett. 134, 226201 (2025)]