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Related Experiment Video

Updated: Feb 16, 2026

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy

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Published on: June 27, 2014

A mapping variable ring polymer molecular dynamics study of condensed phase proton-coupled electron transfer.

Sadrach Pierre¹, Jessica R Duke¹, Timothy J H Hele¹

¹Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA.

The Journal of Chemical Physics

|December 24, 2017

Summary

This study uses advanced molecular dynamics to reveal proton-coupled electron transfer mechanisms. The findings accurately differentiate between concerted and sequential transfer in condensed phases.

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Published on: September 26, 2016

Area of Science:

Chemical Physics
Computational Chemistry
Reaction Dynamics

Background:

Proton-coupled electron transfer (PCET) is crucial in chemical and biological processes.
Understanding PCET mechanisms in condensed phases is complex.
Simulating nonadiabatic excited state dynamics requires sophisticated methods.

Purpose of the Study:

To investigate condensed phase PCET mechanisms using a novel computational approach.
To differentiate between concerted and sequential PCET pathways.
To validate a new simulation methodology for multi-level condensed phase systems.

Main Methods:

Application of Mapping-Variable Ring Polymer Molecular Dynamics (MV-RPMD) to PCET systems.
Construction of system-bath model Hamiltonians with four localized electron-proton states.
Simulation of state population dynamics and comparison with rate theory calculations.

Main Results:

Successfully identified dominant PCET mechanisms for constructed models.
Verified MV-RPMD's ability to distinguish concerted from sequential PCET.
Demonstrated robustness of predicted PCET mechanisms to initial dividing surface choice.

Conclusions:

MV-RPMD is a viable method for simulating multi-level condensed phase PCET dynamics.
The modified MV-RPMD approach with a symmetric Trotter scheme and specific initialization shows promise.
This work advances the computational study of complex electron and proton transfer processes.