Excited states of dicyclohepta[ cd,gh]pentalene: Linear dichroism in a stretched polymer, magnetic circular dichroism, and calculations
Abstract
Ordinary and linear dichroic uv-visible absorption spectra of dicyclohepta[ cd,gh]pentalene have been determined from measurements on solutions in 3-methylpentane and in stretched sheets of ethylene-vinyl acetate copolymer at 77 K. Magnetic circular dichroic spectrum was measured at room temperature. The spectra reveal the presence of numerous separate electronic transitions and permit assignment of state symmetries and of relative direction and sense of some magnetic dipole transition moments between excited states with respect to direction and sense of electric dipole transition moments from ground to these excited states. π-electron calculations account well for the results, including the absolute signs of the peaks in the MCD spectrum (with a single exception).
- Publication:
-
Journal of Molecular Spectroscopy
- Pub Date:
- September 1975
- DOI:
- 10.1016/0022-2852(75)90304-5
- Bibcode:
- 1975JMoSp..57..436K