Abstract
Several oxazine laser dyes have been studied at the air/water interface by the surface-specific technique of second harmonic generation (SHG) spectroscopy. Oxazine 720, cresyl violet, and Nile blue readily form H-aggregate type dimers in aqueous solutions. We report an SHG study of the air/water interface of aqueous solutions of these water-soluble dyes in which it appears that the SHG signals originate almost exclusively from the dimers. The dominance of the dimer in the SHG process holds over a wide range of dye concentration and monomer-to-dimer ratios. The measurements were carried out with incident laser wavelengths near 600 nm, which are resonant with the first electronic transition, and include SHG spectra, solution composition dependence (i.e., dye concentration and salt (NaCl), surfactant, etc.), and polarization dependence. Addition of salt to the dye solutions increases the observed SHG signal intensity to a much greater extent (by as much as a factor of 30) than it promotes bulk aggregation. T...
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
