Primary Events in Vision.
CORNELL UNIV ITHACA N Y SCHOOL OF APPLIED AND ENGINEERING PHYSICS
Pagination or Media Count:
Resonance Raman spectroscopy has been used to study chemically modified retinal analogs involving chain substitutions, ring substitutions or Schiff base linkages. In addition, retinal fragments and fully deuterated retinals were investigated, and infrared spectra of the four isomers of retinal were obtained. Low frequency resonance Raman spectra are also reported for all of the isomers of retinal, for the protonated and unprotonated Schiff bases of trans-retinal, for beta-Ionone and for trans-3-dehydroretinal. Band assignments were made to specific vibrational motions using the results of normal coordinate calculations. These investigations have led to a detailed understanding of the spectral features observed in the resonance Raman spectra of the retinylidene chromophore in rhodopsin and our results form the basis for interpreting the informative Raman spectra of rhodopsin in live eyes. Such investigations should allow, for the first time, a detailed and fundamental understanding of the basis of variations in the sensitivity of the eye to different laser wavelengths. Author