title: Mesitylthio-oligothiophenes in various redox states. Molecular and electronic views as offered by spectroscopy and theory.
abstract: A series of alpha,omega-bis(mesitylthio)oligothiophenes of various chain lengths and with different side substitution patterns have been studied in their oxidized states by means of electron absorption and Raman spectroscopies in combination with theory in the framework of the density functional theory. Upon chemical oxidation, stable radical cations, dications, and even radical trications are generated. Longer chain lengths better stabilize higher oxidation states. The tetramer can be easily converted to the dication, and a trication can be obtained for the ethylenedioxy derivative. The alpha,omega-sulfur atoms are actively involved in the formation of the charged species and exert a favorable tuning of their electronic structure. Raman spectra provide experimental evidence of the attainment of quinoidal structures within the conjugated path, initially heteroaromatic, with different extension as a function of the p-doping level.
authors.affiliation: Department of Physical Chemistry, University of Málaga, Campus de Teatinos s/n, Málaga 29071, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Casado
authors.forename: Marek Z
authors.initials: MZ
authors.lastname: Zgierski
authors.forename: Robin G
authors.initials: RG
authors.lastname: Hicks
authors.forename: Daniel J T
authors.initials: DJ
authors.lastname: Myles
authors.forename: Pedro M
authors.initials: PM
authors.lastname: Viruela
authors.forename: Enrique
authors.initials: E
authors.lastname: Ortí
authors.forename: M Carmen
authors.initials: MC
authors.lastname: Ruiz Delgado
authors.forename: Víctor
authors.initials: V
authors.lastname: Hernández
authors.forename: Juan T
authors.initials: JT
authors.lastname: López Navarrete