Absorption and polarized phosphorescence spectra of substituted s-triazines
Abstract
The ultraviolet absorption spectra of methyl and phenyl derivatives of s-triazine were measured in both polar and nonpolar solvents at room temperature and 77°K. In contrast to s-triazine and the methyl triazines, the orbital assignment of the lowest singlet state of the phenyl triazines cannot be made solely on the basis of the absorption spectra. The polarization of the phosphorescence of the phenyl triazines was determined in rigid glass solutions at 77°K by the method of "photoselection". Excitation spectra of the polarized phosphorescence of the 0-0 band of these phenyl derivatives permits an unambiguous assignment of the lowest singlet as an n, π ∗ type. An outline is given for the derivation of an expression which allows one to obtain a corrected polarization ratio N for detection of the emission at any angle θ relative to the excitation.
- Publication:
-
Journal of Molecular Spectroscopy
- Pub Date:
- May 1968
- DOI:
- 10.1016/0022-2852(68)90140-9
- Bibcode:
- 1968JMoSp..26...24G