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arXiv · 2207.10544

A Semiclassical Framework for Mixed Quantum Classical Dynamics

Shreyas Malpathak·Matthew S. Church·Nandini Ananth
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Abstract

Semiclassical approximations for quantum dynamic simulations in complex chemical systems range from rigorously accurate methods that are computationally expensive to methods that exhibit near-classical scaling with system size but are limited in their ability to describe quantum effects. In practical studies of high-dimensional reactions, neither extreme is the best choice: frequently a high-level quantum mechanical description is only required for a handful of modes, while the majority of environment modes that do not play a key role in the reactive event of interest are well served with a lower level of theory. In this feature we introduce Modified Filinov filtration as a powerful tool for mixed quantum-classical simulations in a uniform semiclassical framework.

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Shreyas Malpathak, Matthew S. Church, Nandini Ananth. 2022-07-21. A Semiclassical Framework for Mixed Quantum Classical Dynamics. https://doi.org/10.1021/acs.jpca.2c03467

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