title: Spectroscopic characterization and theoretical simulation of 1,4-diallylquinoxaline-2,3-dione self dimer.
abstract: Room temperature UV-vis absorption and emission spectra of the 1,4-diallylquinoxaline-2,3-dione (DAQX) are measured in solution at different concentrations. Even at very low concentration (approximately 10(-7)M), DAQX is shown to form ground state van der Waals dimers and excited dimers. These later species do not seem to rearrange into an excimer geometry. The theoretical simulation of the dimer, performed using the analytical atom-atom pair potential described below, predicts a non sandwich face-to-reverse slipped structure with head-to-tail orientation. The allowed absorption transitions, calculated using ZINDO/S package, reproduce satisfactory the experimental spectrum for both the monomer and the simulated dimer.
authors.affiliation: Laboratoire de Spectrométrie, des Matériaux et Archéomatériaux, Université Moulay Ismaïl, Faculté des Sciences, B.P. 11201, Zitoune, Meknès, Morocco.
authors.forename: F
authors.initials: F
authors.lastname: Azzouzi
authors.forename: S
authors.initials: S
authors.lastname: Ait Lyazidi
authors.forename: M
authors.initials: M
authors.lastname: Haddad
authors.forename: M
authors.initials: M
authors.lastname: Lamotte
authors.forename: E M
authors.initials: EM
authors.lastname: Essassi
authors.forename: M
authors.initials: M
authors.lastname: Hnach
authors.forename: M
authors.initials: M
authors.lastname: Zenkouar
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D002725:Chloroform / Q000737:chemistry; D019281:Dimerization; D011810:Quinoxalines / Q000737:chemistry*; D012399:Rotation; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D055672:Static Electricity; D013696:Temperature
chemical_list: C522983:1,4-diallylquinoxaline-2,3-dione; D000097:Acetonitriles; D011810:Quinoxalines; D002725:Chloroform; C032159:acetonitrile