Modular Face-to-Face Assembly of Multichromophore Arrays That Absorb Across the Complete UV−Visible Spectrum and into the Near-IR

Defined face-to-face structures of phthalocyanine and porphyrin chromophores can be prepared using a modular strategy that allows directional, stepwise construction. μ-Oxo linkage between the central group of 14 metalloid atoms Si and Ge ensures π-overlap between the macrocycles, and exciton coupling effects further extend the absorption profile to provide arrays that absorb across the whole UV−visible spectrum and into the near-IR. The strategy is sufficiently versatile to be extended to synthesis of higher defined oligomers and subsequent functionalization or attachment at either or both ends of the stack.