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An in‐depth study of donor‐acceptor (D/A) interactions between the high‐dipole acceptor C60F18 (A) and PAH donors — pyrene, perylene, and coronene — reveals a surprisingly strong PAH size influence on the D/A complex stoichiometry and  ordering  in co‐crystals, and on the surface of PAH monolayers deposited on Au(111). Crystallographic study shows the tendency of the D/A mixtures to form stacked layered structures, such as D/A/D/A  or  D/A/A/D/A/A , for larger PAHs, perylene and coronene, respectively, while the role of aromatic π–π interactions diminishes, in contrast to Pyrene/C60F18 system. Attempts to achieve similarly ordered D/A assemblies on surfaces, by sequential deposition or co‐evaporation of C60F18 and coronene on Au(111), are presented. Scanning tunneling microscopy (STM) shows that the flat lying configuration adopted by coronene, which forms a highly‐ordered close‐packed monolayer stabilized by the interaction between their π electrons and the high density of gold surface states, hinders the formation of ordered co‐crystals. The critical role played by electronic and steric effects in the co‐crystal formation are believed to be at the basis of such lack of viability. However, adsorbed single C60F18 molecules are revealed to be centered on top of one coronene molecule, facilitating charge transfer between D and A molecules. 

By investigating second coordination sphere effects on the magnetic anisotropy of a Co(ii) single molecule magnet (SMM), we aim to clarify their role in magneto-structural correlations to enhance the performance of transition metal SMMs. 

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. 

Solid state UV-vis reflectance spectra reveal the distinct electronic structure of POM@MOF materials obtained by synthetic encapsulation of mono- and di-vanadium substituted Keggin polyoxotungstates in HKUST-1.