Spectra of radical cations of phenothiazine derivatives in solution and solid state.

The UV and visible spectra of radical cations of several phenothiazine derivatives were studied using different solvents. The establishment of a relationship between these bands and the R2 and R10 substituents was attempted. The influence of the disolvents on the bands also was studied. The characteristic charge transfer band was observed in the solid state using diffuse reflectance spectroscopy. The R2 substituent did not appear to influence the band, while the R10 substituent influenced the band considerably, probably due to steric effects.