title: Detection of Circularly Polarized Luminescence of a Cs-Eu(III) Complex in Raman Optical Activity Experiments.
abstract: Circularly polarized luminescence (CPL) spectra are extremely sensitive to molecular structure. However, conventional CPL measurements are difficult and require expensive instrumentation. As an alternative, we explore CPL using Raman scattering and Raman optical activity (ROA) spectroscopy. The cesium tetrakis(3-heptafluoro-butylryl-(+)-camphorato) europium(III) complex was chosen as a model as it is known to exhibit very large CPL dissymmetry ratio. The fluorescent bands could be discriminated from true Raman signals by comparison of spectra acquired with different laser excitation wavelengths. Furthermore, the ROA technique enables fluorescence identification by measuring the degree of circularity. The CPL dissymmetry ratio was measured as the ROA circular intensity difference of 0.71, the largest one ever reported. The alternative CPL measurement enhances applications of lanthanides in analytical chemistry and chemical imaging of biological objects.
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Flemingovo nám. 2, 16610 Prague 6 (Czech Republic). wu@uochb.cas.cz.
authors.forename: Tao
authors.initials: T
authors.lastname: Wu
authors.affiliation: Department of Optics, Palacký University Olomouc, 17. listopadu 12, 77146 Olomouc (Czech Republic). kapitan@optics.upol.cz.
authors.forename: Josef
authors.initials: J
authors.lastname: Kapitán
authors.affiliation: Institute of Molecular and Translational Medicine, Palacký University Olomouc, Hněvotínská 5, 77900 Olomouc (Czech Republic).
authors.forename: Vlastimil
authors.initials: V
authors.lastname: Mašek
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Flemingovo nám. 2, 16610 Prague 6 (Czech Republic). bour@uochb.cas.cz.
authors.forename: Petr
authors.initials: P
authors.lastname: Bouř
keywords: Raman imaging; Raman optical activity; chiral fluorescent chromophores; circularly polarized luminescence; lanthanides