A new class of acceptor-substituted S,N-heteropentacenes is developed for vacuum-processed organic solar cells, providing encouraging power conversion efficiencies of up to 6.5%. Atomic force microscopy (AFM) investigations give a direct correlation between the blend film morphology and the photovoltaic parameters, such as short-circuit current density (JSC ) and fill factor (FF).

Sterically crowded and twisted thienylene‐phenylenes were synthesized and characterized in comparison to corresponding polyphenylene nanostructures. Spectroscopic, diffraction, and theoretical studies gave evidence of through‐space delocalization of π‐electrons of peripheral (hetero)aromatic rings in toroidal and catenated topologies.

Acceptor-substituted S,N-heteropentacenes with systematically varied alkyl side chains were prepared and implemented as donors in vacuum-processed OSCs giving devices with efficiencies in the range of 4–6%. An odd–even effect with respect to the length of the alkyl side chains is noted.

Dedicated to Prof. Dr. Dr. h.c. Klaus Müllen on the occasion of his 75 th birthday Sterically highly crowded and twisted thienylene-phenylenes are synthesized and structurally characterized. Single-crystal X-ray structure analyses and theoretical studies give evidence of through-space delocalization of 𝝅-electrons of peripheral (hetero)aromatic rings in toroidal and catenated topology.