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An in‐depth study of donor–acceptor (D/A) interactions between the high‐dipole acceptor C₆₀F₁₈(A) and polycyclic aromatic hydrocarbon (PAH) donors—pyrene, perylene, and coronene—reveals a surprisingly strong PAH size influence on the D/A complex stoichiometry and ordering in co‐crystals. The crystallographic study shows the tendency of D/A mixtures to form stacked layered structures for the larger PAHs, perylene and coronene, while the role of aromatic π–π interactions diminishes, in contrast to the smaller pyrene/C₆₀F₁₈system. The behavior of the layered‐D/A assemblies is investigated by utilizing sequential deposition and co‐evaporation of C₆₀F₁₈and coronene on Au(111) surfaces. Scanning tunneling microscopy shows that the flat lying configuration adopted by coronene on the metal, which forms highly ordered close‐packed monolayers stabilized by the interaction between their π electrons and the high density of gold surface states, hinders the formation of the ordered assemblies of the corresponding co‐crystal. The influence of the substrate plus the critical role played by electronic and steric effects in the co‐crystal formation are believed to cause the lack of viability. However, it is remarkable that, on the surface, adsorbed single C₆₀F₁₈molecules are well centered on top of one coronene molecule, facilitating charge transfer between D and A molecules. 

A new deep-blue emitting and highly fluorescent anthracene (ANTH) derivative containing perfluorobenzyl (Bn_F) groups, 9,10-ANTH(Bn_F)₂, was synthesized in a single step reaction of ANTH or ANTH(Br)₂with Bn_FI, using either a high-temperature Cu-/Na₂S₂O₃-promoted reaction or via a room-temperature photochemical reaction. Its structure was elucidated by NMR spectroscopy and single crystal X-ray diffractometry. The latter revealed no π–π interaction between neighboring ANTH cores. A combination of high photoluminescence quantum yield (PLQY) of 0.85 for 9,10-ANTH(Bn_F)₂, its significantly improved photostability compared to ANTH and 9,10-ANTH derivatives, and a simple synthetic access makes it an attractive material as a deep-blue OLED emitter and an efficient fluorescent probe.