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Title: Reduced-dimensional surface hopping with offline–online computations
Molecular dynamics simulations often classically evolve the nuclear geometry on adiabatic potential energy surfaces (PESs), punctuated by random hops between energy levels in regions of strong coupling, in an algorithm known as surface hopping. However, the computational expense of integrating the geometry on a full-dimensional PES and computing the required couplings can quickly become prohibitive as the number of atoms increases. In this work, we describe a method for surface hopping that uses only important reaction coordinates, performs all expensive evaluations of the true PESs and couplings only once before simulating dynamics (offline), and then queries the stored values during the surface hopping simulation (online). Our Python codes are freely available on GitHub. Using photodissociation of azomethane as a test case, this method is able to reproduce experimental results that have thus far eluded ab initio surface hopping studies.  more » « less
Award ID(s):
1745654 1906446
NSF-PAR ID:
10290182
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Physical Chemistry Chemical Physics
ISSN:
1463-9076
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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