butyl groups formed two types of emissivesolids that display bluish green and blue fluorescence (ΦF=72 and 32 %, respectively), depending on the preparation conditions. The crystal and powder X‐ray analyses reveal that the highly emissivesolid adopts a head‐to‐head arrangement with discrete stacks of the anthracene moieties, whereas the moderately emissivesolid adopts a head‐to‐tail arrangement