Extending SHARC to Periodic Systems: A SHARC–VASPInterface for First-Principles Nonadiabatic Dynamics

Abstract Nonadiabatic effects arising from the breakdown of the Born–Oppenheimer approximation govern a wide range of photoinduced processes in molecules and materials. While trajectory surface hopping has become a standard tool for simulating excited-state dynamics in molecular systems, its extension to periodic solids remains comparatively underdeveloped. In this work, we present an interface between the trajectory surface hopping package Surface Hopping including Arbitrary Couplings (SHARC) and the plane-wave density functional theory code Vienna Ab initio Simulation Package (VASP) that enables nonadiabatic dynamics simulations in periodic solids based on first-principles electronic-structure calculations. This development extends the applicability of SHARC from finite molecular systems to extended materials while retaining its modularity and support for arbitrary electronic couplings. Further, it provides a broadly applicable platform for investigating excited-state dynamics in solids using concepts and workflows familiar from the molecular nonadiabatic dynamics community, thereby establishing a unified theoretical and computational framework for both molecular and extended materials. As a first application, the interface is tested on bulk silicon, a prototypical semiconductor whose photoinduced carrier relaxation dynamics is strongly influenced by electron–phonon coupling and has therefore been extensively investigated both experimentally and theoretically.