Polymorphism in a Highly Conjugated Organic Compound: Strong Photoelectric Response

4′-(4-{2-[4-(N,N-diphenylamino)phenyl]ethenyl}phenyl)-2,2′:6′,2′′-terpyridine is a highly conjugated compound, which is used to grow polymorphs. The results obtained suggest that polymorphs could appear as the Eu3+/Ag+-induced feature. Only three intermolecular C−H···π interactions stabilize the polymorph A in monoclinic space group C2/c with Z = 8, while five intermolecular C−H···π interactions assume completely new pattern to arrange the Eu3+/Ag+-induced polymorph B in monoclinic space group P21/c with Z = 4. The changes in patterns of the C−H···π interactions could impose on the molecular conformation, induced dipole, electronic delocalization and intra- and intermolecular electron transfer transition, and thus give rise to the very different photoelectric response for polymorphic forms.