title: Interpretation of cw-ESR spectra of p-methyl-thio-phenyl-nitronyl nitroxide in a nematic liquid crystalline phase.
abstract: In this paper we report on the characterization by continuous wave electron spin resonance spectroscopy (cw-ESR) of a nitronyl nitroxide radical in a nematic phase. A detailed analysis is performed by exploiting an innovative modeling strategy alternative to the usual spectral simulation approach: most of the molecular parameters needed to calculate the spectrum are evaluated a priori and the ESR spectrum is obtained by direct application of the stochastic Liouville equation. Allowing a limited set of fitting parameters it is possible to reproduce satisfactorily ESR spectra in the temperature range 260 K-340 K including the nematic-to-isotropic phase transition (325.1 K). Our results open the way to a more quantitative understanding of the ordering and mobility of nitronyl nitroxide radicals in nanostructured environments.
authors.affiliation: Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via Marzolo, I-35131 Padova, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Collauto
authors.forename: Mirco
authors.initials: M
authors.lastname: Zerbetto
authors.forename: Marina
authors.initials: M
authors.lastname: Brustolon
authors.forename: Antonino
authors.initials: A
authors.lastname: Polimeno
authors.forename: Andrea
authors.initials: A
authors.lastname: Caneschi
authors.forename: Dante
authors.initials: D
authors.lastname: Gatteschi