Journal article
Optical absorption and magnetic circular dichroism spectra of thiouracils: a quantum mechanical study in solution
The excited electronic states of 2-thiouracil, 4-thiouracil and 2,4-dithiouracil, the analogues of uracil where the carbonyl oxygens are substituted by sulphur atoms, have been investigated by computing the magnetic circular dichroism (MCD) and one-photon absorption (OPA) spectra at the time-dependent density functional theory level.
Special attention has been paid to solvent effects, included by a mixed discrete/continuum model, and to determining how our results depend on the adopted DFT functional (CAM-B3LYP and B3LYP). Whereas including solvent effects does not dramatically impact the MCD and OPA spectra, though improving the agreement with the experimental spectra, the performances of CAM-B3LYP and B3LYP are remarkably different.
CAM-B3LYP captures well the effect of thionation on the uracil excited states and provides spectra in good agreement with the experiments, whereas B3LYP shows some deficiency in describing 2-TU and 2,4-DTU spectra, despite being more accurate than CAM-B3LYP for 4-TU.
Language: | English |
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Publisher: | Springer International Publishing |
Year: | 2017 |
Pages: | 1415-1423 |
ISSN: | 14749092 and 1474905x |
Types: | Journal article |
DOI: | 10.1039/c7pp00105c |
ORCIDs: | 0000-0001-5361-9390 , Coriani, Sonia and 0000-0003-1004-195X |