title: Electronic, structural and vibrational induced effects upon ionization of 2-quinolinone.
abstract: Using first principle methodologies, we characterize the lowest electronic states of 2-quinolinone(+) cation. The ground state of this ion is of X˜(2)A(″) nature. We deduce the adiabatic ionization energy of 2-quinolinone to be equal 8.249eV using the explicitly correlated coupled cluster level and where zero point vibrational energy, core-valence and scalar relativistic effects are taken into account. We examine also the ionization induced structural changes and vibrational shifts and analyze the electron density differences between the neutral and ionic species. These data show that the formation of 2-quinolinone(+)X˜(2)A(″) from 2-quinolinone affects strongly the HNCO group, whereas the carbon skeletal is perturbed when the upper electronic cationic states are populated. The comparison to 2-pyridone allows the elucidation of the effect of benzene ring fused with this heterocyclic ring. Since quinolones and pyridones are both model systems of DNA bases, these findings might help in understanding the charge redistribution in these biological entities upon ionization.
authors.affiliation: Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée, France.
authors.forename: A
authors.initials: A
authors.lastname: Bellili
authors.affiliation: Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong.
authors.forename: Y
authors.initials: Y
authors.lastname: Pan
authors.affiliation: Chemistry Department, Faculty of Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia.
authors.forename: M M
authors.initials: MM
authors.lastname: Al Mogren
authors.affiliation: Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong. Electronic address: kaichung@cityu.edu.hk.
authors.forename: K C
authors.initials: KC
authors.lastname: Lau
authors.affiliation: Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée, France. Electronic address: hochlaf@univ-mlv.fr.
authors.forename: M
authors.initials: M
authors.lastname: Hochlaf
mesh_terms: D004247:DNA / Q000737:chemistry; D004583:Electrons; D007477:Ions / Q000737:chemistry; D008958:Models, Molecular; D011728:Pyridones / Q000737:chemistry; D015363:Quinolones / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D007477:Ions; D011728:Pyridones; D015363:Quinolones; D004247:DNA
keywords: 2-Quinolone cation; Ab initio computations; DNA analogs; Electronic states; Ionization energies