Optical dichroism lattice

Such a spectrum is interpreted in terms of exciton interactions between the retinals within the trimer clusters (41,42,279-282) which characterize the purple membrane lattice (cf. Section I-B). Although this conclusion is generally accepted, the details of the exciton-interaction model may have to be revised. For example, the current exciton models (41,42) predict a low-intensity, out-of-the-membrane-plane optical transition on the high-energy side of the main absorption band, which is in varianceo with linear dichroism spectra (254). Moreover, the 9- to 12-A distance between chromophores predicted by these models are not compatible with recent neutron diffraction data (283). 

Suryanarayanan et al. (1972) have shown that the results obtained by magnetic circular dichroism are in good agreement with those of Holtzberg and Torrance (1971). The lattice parameter of the fee unit cells are 6.20 A for SmSe and 6.60 A for SmTe. Magneto-optical properties have been reported by Paparoditis and Suryanarayanan (1972). 

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