@article{IBB_ID_53478,
author={Cerezo J, Martinez-fernandez L, Improta R, Santoro F},
title={Vibronic approach to the calculation of the decay rate of the photoexcited charge-transfer state of Guanine-Cytosine stacked dimer in water solution},
date={2016 Sep},
journal={Theoretical Chemistry Accounts},
year={2016},
fullvolume={253},
volume={253},
pages={N/D--N/D},
url={},
abstract={We compute the rate of the charge recombination (CR) process from the
minimum of the charge transfer (CT) Guanine–Cytosine stacked dimer in
water solution to the ground electronic state (GS). We adopt the quantum
non-adiabatic theory of electron transfer reactions, where key
ingredients to determine the CR rate are the electronic coupling and the
so-called Franck–Condon density of states (FCWD). In order to compute
the FCWD, we exploited recent developments in the field of the
time-independent and time-dependent simulations of vibronic spectra of
large systems, based on model harmonic potential energy surfaces (PESs).
Both mean-field solvent effects on the PESs and the solvent
reorganization effects on the CR rate were described by implicit
polarizable continuum model. We show that an improper treatment of the
contributions of the inter-base modes to the FCWD results in artefacts
which can change the estimate of the CR rates by orders of magnitude and
we devise a computational protocol in internal coordinates able to
determine “effective normal modes” that separate the stiff (intra-base)
modes and the inter-base ones. The results for the CR rate are
qualitatively consistent with available experimental data. By computing
the CR rate for four different stacking geometries, we show that all the
parameters ruling the CR rate, namely the CT character of the excited
state (ES), the equilibrium position of stiff modes (and therefore the
FCWD), the electronic coupling and the energy gap between the GS and ES
are all strongly dependent on the fluctuation of the dimer structure
along the inter-base modes. On this ground, we discuss some possible
future theoretical developments to achieve a non-phenomenological fully
first-principle estimate of the CR rate that can be directly compared
with experiment.},
keywords={, },
references={},
document_type={, },
affiliation={},
ibbaffiliation={1},
}