Correlated fluctuations in the exciton dynamics and spectroscopy of DNA

TL;DR

This paper investigates how correlated environmental fluctuations influence exciton dynamics in DNA and demonstrates their impact on spectroscopic signals, providing insights into DNA photo damage mechanisms.

Contribution

It introduces a model accounting for environmental fluctuation correlations and shows their significant effect on exciton behavior and spectroscopic observations.

Findings

Correlations significantly alter exciton dynamics.

Correlations affect anisotropy decay in spectroscopy.

Model explains experimental spectroscopic features.

Abstract

The absorption of ultraviolet light creates excitations in DNA, which subsequently start moving in the helix. Their fate is important for an understanding of photo damage, and is determined by the interplay of electronic couplings between bases and the structure of the DNA environment. We model the effect of dynamical fluctuations in the environment and study correlation, which is present when multiple base pairs interact with the same mode in the environment. We find that the correlations strongly affect the exciton dynamics, and show how they are observed in the decay of the anisotropy as a function of a coherence and a population time in a non-linear optical experiment.