Several photophysical properties of chromophores depend crucially on intermolecular interactions. Thermally‐activated delayed fluorescence (TADF) is often influenced by close packing of the chromophore assembly. In this context, the metal‐organic framework (MOF) approach has several advantages: it can be used to steer aggregation such that the orientation within aggregated structures can be predicted using rational approaches. We demonstrate this design concept for a DPA‐TPE (diphenylamine‐tetraphenylethylene) chromophore, which is non‐emissive in its solvated state due to vibrational quenching. Turning this DPA‐TPE into a ditopic linker makes it possible to grow oriented MOF thin films exhibiting pronounced green electroluminescence with low onset voltages. Measurements at different temperatures clearly demonstrate the presence of TADF. Finally, this work reports that the layer‐by‐layer process used for MOF thin film deposition allows the integration of the TADF‐DPA‐TPE in a functioning LED device.

Pentacene assembled into 1D arrays using a metal–organic framework (MOF) approach. This cofacial packing motif, which is not present in pentacene bulk, shows an interesting interplay of band-like and hopping-type transport.

While materials based on organic molecules usually have either superior optoelectronic or superior chiral properties, the combination of both is scarce. Here, a crystalline chiroptical film based on porphyrin with homochiral side groups is presented. While the dissolved molecule has a planar, thus, achiral porphyrin core, upon assembly in a metal–organic framework (MOF) film, the porphyrin core is twisted and chiral. The close packing and the crystalline order of the porphyrin cores in the MOF film also results in excellent optoelectronic properties. By exciting the Soret band of porphyrin, efficient photoconduction with a high On‐Off‐ratio is realized. More important, handedness‐dependent circularly‐polarized‐light photoconduction with a dissymmetry factor g of 4.3×10⁻⁴ is obtained. We foresee the combination of such assembly‐induced chirality with the rich porphyrin chemistry will enable a plethora of organic materials with exceptional chiral and optoelectronic properties.