Effects of chromophore interaction in photophysics and photochemistry of cyanine dyes. (2000)

• Record Type: Journal Article
• Authors: Tatikolov, A. S.; Krasnaya, Zh. A.; Shvedova, L. A.; Kuzmin, V. A.
• Is Part Of: International journal of photoenergy. Volume 2:Number 1(2000)
• Page Start: 23
• Page End: 30
• Publication Date: 2000
• Subjects: Photochemistry -- Periodicals; Photobiology -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Photochimie; Photobiologie; Chimie physique et théorique; Chemistry, Physical and theoretical; Photobiology; Photochemistry; Electronic journals; Periodicals; 541.35
• DOI: 10.1155/S1110662X00000040
• Languages: English
• ISSNs: 1110-662X

Abstract

Abstract : Spectral and fluorescent properties of ketocyanine dyes (polyenic bis-ω, ω ′ -aminoketones) and cation-anionic polymethine dyes of various structures were studied. The symmetric ketocyanines were shown to have a long-wavelength absorption band bathochromically shifted in comparison with that of the asymmetric ketocyanines with the same total length of the polyenic chain. The nonlinear ketocyanines exhibit the additional short-wavelength band in their absorption spectra, which can be more intense than the longwavelength band. The absorption spectra of ion pairs of cation-anionic dyes with overlapping cation and anion bands contain a new intense short-wavelength band inactive in fluorescence excitation. These spectral peculiarities are explained on the basis of chromophore interaction model. It has also been shown that theT 1 levels of ketocyanine chromophores do not essentially interact with each other in a ketocyanine molecule in nonpolar solvents; in polar solvents this interaction becomes appreciable due to lowering the potential barrier for conjugation.