Conformational change of all-trans-1,6-diphenyl-1,3,5-hexatriene in two crystalline forms

Abstract

The crystal structures of all-trans-1,6-diphenyl-1,3,5-hexatriene in two polymorphic forms were examined by X-ray diffraction analysis at various temperatures. In both crystal forms, a misoriented minor conformer was observed at higher temperatures, and it disappeared at lower temperatures. The temperature dependence of the crystal structures was accounted for in terms of a conformational change through pedal motions in crystals.