Elements: Libra: The Modular Software for Nonadiabatic and Quantum Dynamics

Sustained progress in scientific endeavors in solar energy, functional, and nanoscale material sciences requires advanced methods and software components that can be used to model the complex dynamics of excited states, including charge and energy transfer. Within this project, we develop the open-source Libra software which implements a multitude of community-developed methods and computational workflows for nonadiabatic and quantum dynamics (NA/QD) calculations. We focus on trajectory surface hopping methods, decoherence schemes, state tracking algorithms, and more. We interface Libra with various electronic structure codes and excited state calculation methods, enabling it to treat bigger systems and use higher levels of theory in materials modeling. We develop a database of analytic Hamiltonians and conduct a systematic assessment of various NA/QD methods to standardize and rank the “zoo” of the presently available NA/QD methods.