Intensity of the long-wavelength UV transition of vitamin E

The intensity of the long-wavelength UV transition of tocopherols is invest igated using the interaction vector model. Intensity of alpha -tocopherol i s the lowest of the series because it is the molecule which allows the most efficiently the effects of the alkyl groups to oppose the effects on inten sity of the two alkoxy-like groups (a hydroxy group and a fused trimethylen eoxy moiety). Intensity of eta -tocopherol is the highest because the only methyl substituent cannot attenuate the effects of the alkoxy-like groups.