The Absorption Spectrum of Guanine Based Radicals: a Comparative Computational Analysis
| Autor: | Sonia Coriani, Roberto Improta, Haritha Asha, Lara Martínez Fernández, Javier Cerezo, Fabrizio Santoro |
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| Rok vydání: | 2019 |
| Předmět: |
Materials science
Computational photochemistry 010304 chemical physics Absorption spectroscopy Guanine Radical Organic Chemistry DNA 010402 general chemistry Ab inito calculations 01 natural sciences Quantum chemistry 0104 chemical sciences Analytical Chemistry Quantum chemisty chemistry.chemical_compound Organic radicals chemistry Ab initio quantum chemistry methods Computational chemistry 0103 physical sciences Computational analysis Physical and Theoretical Chemistry Solvent effects |
| Zdroj: | Martínez Fernández, L, Cerezo, J, Asha, H, Santoro, F, Coriani, S & Improta, R 2019, ' The absorption spectrum of guanine based radicals: a comparative computational analysis ', ChemPhotoChem, vol. 3, no. 9, pp. 846-855 . https://doi.org/10.1002/cptc.201900107 ChemPhotoChem |
| ISSN: | 2367-0932 |
| DOI: | 10.1002/cptc.201900107 |
| Popis: | The excited states of the three radical derivatives of guanine, i.e. guanine cation (G+) and its two main deprotonated derivatives (G-H1 and G-H2) have been characterized in the Franck-Condon region by TD-DFT, using different functionals, CASPT2, and EOM-EE-CCSD calculations. In the gas phase, all the methods provide a similar description of the main spectral features, the pictures provided by TD-DFT, with long range corrected functionals, and EOM-EE-CCSD being very close. Solvent effects are then taken into account by a mixed discrete-continuum approach, including five water molecules of the first solvation shell and the Polarizable Continuum Model (PCM). The vibronic absorption line-width has finally been simulated at the TD-M052X level by a time dependent method within the harmonic approximation. The resulting absorption spectra are in good agreement with their experimental counterparts, providing useful indications on the use of PCM/TD-DFT based approaches to interpret the spectra of guanine based radicals within DNA. |
| Databáze: | OpenAIRE |
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