Letter | Published:

Photoinduced Free Radicals of Visual Pigments in Solutions mobile at −196° C


IN rigid solutions of visual pigments stabilized for studies of electron spin resonance (ESR) at the temperature of liquid nitrogen white irradiation creates free radicals with resonance patterns consisting of broad singlets1. We have obtained more refined information by providing solvents mobile at these low temperatures and by irradiation of the visual pigments with selected monochromatic beams rather than with white light.

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