The Key Role of Molecular Packing in Luminescence Property: From Adjacent Molecules to Molecular Aggregates

Abstract The luminescence materials act as the key components in many functional devices, as well as the detection and imaging systems, which can be permeated in each aspect of modern life, and attract more and more attention for the creative technology and applications. In addition to the diverse properties of organic luminogens, the multiple molecular packing at aggregated states frequently offers new and/or exciting performance. However, there still lacks comprehensive analysis of molecular packing in these organic materials, resulting in an increased gap between molecular design and practical applications. In this review, from the basic knowledge of organic compounds as single molecules, to the discernable property of excimer, charge transfer (CT) complex or self‐assembly systems by adjacent molecules, and finally to the opto‐electronic performance of molecular aggregates, the relevant factors to molecular packing and practical applications are discussed.