Strategies for tailoring clusteroluminescence: from aggregation control to molecular engineering.

Clusteroluminescence (CL), light emission from non-conventional systems via through-space interaction (TSI), offers unique photophysical properties distinct from traditional luminophores. This review outlines dual-level strategies for tailoring CL: aggregation regulation and molecular engineering. Controlling aggregation via crystalline or amorphous packing, spatial confinement, and microenvironment design modulates cluster formation and TSI efficiency. Molecular approaches, such as heteroatom incorporation, substituent tuning, and conformational control, enable precise manipulation of electronic structure and emission pathways. Interplay between these levels allows tunable, efficient, and multifunctional CL. By integrating recent advances, we provide a systematic framework to guide rational design of clusteroluminogens (CLgens) toward next-generation luminescent materials.