1. The determination of solid-liquid phase diagrams in ten pairs of symmetrically substituted sulfoxides and sulfones showed the formation of continuous series of mixed crystals. 2. Sulfides do not form mixed crystals with sulfoxides or sulfones in the wide ranges studied. 3. These results prove that sulfoxides and sulfones have the same steric configuration. Attributing to the sulfones a tetrahedral configuration the same applies also to the ...
