Multicomponent Molecular Assembly of Fluorescent Organic Semiconductors Beyond Three Compounds.

In contrast to unary assemblies comprising π‐conjugated organic species, elaborate modulation of dimensions, polymorphisms, and compositions of multicomponent assembled architectures with two or more constituent materials has not yet been systematically studied. Herein, a combinatorial library of organic microcrystals made of four components via a solution‐phase assembly route is reported. With the involvement of growth kinetics, four organic species with slight structural modifications can assemble into five unary assemblies, which may endow binary combinations with highly and partially structural miscibility. Consequently, a variety of binary alloyed assemblies and microscale heterostructures with tailorable dimensions, polymorphisms, and emission colors are realized by rational compositional and growth control. The effects of structural relations of binary combinations on their miscibility are systematically uncovered, that gives rise to these intricate microscale architectures as well as diverse energy transfer (ET) efficiencies. Highly efficient ET process in binary alloyed assemblies can be beneficial to steady‐state photoluminescence anisotropy amplification. Benefiting from the information of binary combinations, white‐light‐emitting ternary microsheets can be modulated in a predictable manner. The present work uncovers the rational control of multicomponent microcrystals, which further stretches the boundaries of molecular self‐assembly and may be used to achieve integrated optoelectronic properties, such as multicolor lasers and p–n junctions. [ABSTRACT FROM AUTHOR]