Newton-X Platform: New Software Developments for Surface Hopping and Nuclear Ensembles

Abstract

Newton-X is an open-source computational platform to perform nonadiabatic molecular dynamics based on surface hopping and spectrum simulations using the nuclear ensemble approach. Both are among the most common methodologies in computational chemistry for photophysical and photochemical investigations. This paper describes the main features of these methods and how they are implemented in Newton-X. It emphasizes the newest developments, including zero-point-energy leakage correction, dynamics on complex-valued potential energy surfaces, dynamics induced by incoherent light, dynamics based on machine-learning potentials, exciton dynamics of multiple chromophores, and supervised and unsupervised machine learning techniques. Newton-X is interfaced with several third-party quantum-chemistry programs, spanning a broad spectrum of electronic structure methods.

Investigating the factors that influence sacrificial hydrogen evolution activity for three structurally-related molecular photocatalysts: thermodynamic driving force, excited-state dynamics, and surface interaction with cocatalysts

“…To probe the dynamic properties of the first two excited states of molecules 1 to 3 upon light absorption and excitation, we performed nonadiabatic molecular dynamics simulations in gas phase using the Newton-X package. 26,33–35…”

Surface hopping modeling of charge and energy transfer in complex environments

“…The potential energy difference between the states at the hopping time is added to the nuclear kinetic energy. Surface hopping has been extensively applied to investigate internal conversion, intersystem crossing, 12 and photon-induced 13 transitions in systems ranging from analytical models, 14 through small molecules, 15 to large supramolecular ensembles. 10 Surface hopping is a local theory, meaning that the electronic quantities needed to propagate the equations of motion (potential energies, potential energy gradients, and nonadiabatic couplings) are computed only for the nuclear geometries of the classical trajectory.…”

“…The plot shows 100 random points for each of these electronic densities. The nuclear density was calculated with Newton-X, 15 and electronic densities with Gaussian 16. 150 The proton delocalization problem was recognized in the early 1990s when Hammes-Schiffer and Tully published one of the first applications of surface hopping to proton transfer in solution.…”

“…83 Their methodology is not restricted to FOMO-CI and can be adapted to other electronic structure methods. In Newton-X, 15 for example, it is implemented for FOMO-CI and TDDFT.…”

Efficient implementation and performance analysis of the independent electron surface hopping method for dynamics at metal surfaces

“…This is facilitated by the NQCModels.jl framework previously introduced as part of NQCDynamics.jl. 33 Although a number of popular software solutions exist for TSH methods, [35][36][37] these do not currently treat metallic systems using IESH. When benchmarking IESH with one dimensional models, it has been previously compared to Marcus theory 11,13 but not a numerically exact method such as the HQME.…”