@article{
author = "Milovanović, Branislav and Stanković, Ivana and Petković, Milena and Etinski, Mihajlo",
year = "2020",
abstract = "Guanine self-assemblies are promising supramolecular
platforms for optoelectronic applications. The study (Hua et al., J. Phys. Chem. C 2012, 116, 14,682−14,689) reported that alkaline cations cannot modulate the electronic absorption spectrum of G-quadruplexes, although a cation effect is observable
during electronic relaxation due to different mobility of Na+ and K+ cations. In this work, we theoretically examined whether divalent Mg2+ and Ca2+ cations and hydration might shift excited charge-transfer states of a cation-templated stacked G-quartet to the absorption red tail. Our results showed that earth alkaline cations
blue-shifted nπ* states and stabilized charge-transfer ππ* states relative to those of complexes with alkaline cations, although the number of charge-separation states was not significantly modified. Earth alkaline cations were not able to considerably increase the
amount of charge-transfer states below the Lb excitonic states. Hydration shifted charge-transfer states of the Na+-coordinated Goctet to the absorption red tail, although this part of the spectrum was still dominated by monomer-like excitations. We found Goctet electron detachment states at low excitation energies in aqueous solution. These states were distributed over a broad range of excitation energies and could be responsible for oxidative damage observed upon UV irradiation of biological G-quadruplexes.",
publisher = "American Chemical Society (ACS)",
journal = "The Journal of Physical Chemistry A",
title = "Modulating Excited Charge-Transfer States of G‑Quartet Self- Assemblies by Earth Alkaline Cations and Hydration",
volume = "124",
number = "40",
pages = "8101-8111",
doi = "10.1021/acs.jpca.0c05022"
}