title: Photoelectron spectroscopic and density functional theoretical studies of the 2'-deoxycytidine homodimer radical anion.
abstract: The intact (parent) 2'-deoxycytidine homodimer anion, (dC)2 (●-), was generated in the gas phase (in vacuo) using an infrared desorption∕photoemission source and its photoelectron spectrum was recorded using a pulsed, magnetic bottle photoelectron spectrometer. The photoelectron spectrum (PES) revealed a broad peak with the maximum at an electron binding energy between 1.6 and 1.9 eV and with a threshold at ∼1.2 eV. The relative energies and vertical detachment energies of possible anion radicals were calculated at the B3LYP/6-31++G(∗∗) level of theory. The most stable anion radicals are the complexes involving combinations of the sugar[middle dot][middle dot][middle dot]base and base[middle dot][middle dot][middle dot]base interactions. The calculated adiabatic electron affinities and vertical detachment energies of the most stable (dC)2 (●-) anions agree with the experimental values. In contrast with previous experimental-computational studies on the anionic complexes involving nucleobases with various proton-donors, the electron-induced proton transferred structures of (dC)2 (●-) are not responsible for the shape of PES.
authors: Department of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-952 Gdańsk, Poland. pondros@chem.univ.gda.pl
authors: Piotr
authors: P
authors: Storoniak
authors: Janusz
authors: J
authors: Rak
authors: Yeon Jae
authors: YJ
authors: Ko
authors: Haopeng
authors: H
authors: Wang
authors: Kit H
authors: KH
authors: Bowen
mesh_terms: D000838:Anions / Q000737:chemistry; D003841:Deoxycytidine / Q000737:chemistry*; D019281:Dimerization; D005609:Free Radicals / Q000737:chemistry; D056951:Photoelectron Spectroscopy; D011789:Quantum Theory
chemical_list: D000838:Anions; D005609:Free Radicals; D003841:Deoxycytidine