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The absorption spectrum of single and oriented crystals of iodine has been investigated in the wavelength region 7000–3000 A. Four strongly polarized bands and one weakly polarized absorption band have been observed, all of which are polarized in the ac plane of the crystal. All of the absorption bands are approximately 1000 cm−1 wide. The crystal‐band theory for iodine given by Rosenberg has been extended, and the effects of exchange and of spin—orbit coupling have been qualitatively considered. Three models are discussed with varying relative importance of spin—orbit and crystal energies. These models are correlated, and the strong crystal force model is used to interpret the experimental observations.