Charge‐Transfer Exciton Flows: Red Luminescent Zn ₈ D ₁₄ A ₄ Nanotubes

Precise arrangement of multi‐electron‐donor (D) and acceptor (A) molecules can drive directional flows of photo‐generated molecular excitons and charge‐transfer (CT) excitons along with the proper D–A sequence. Here, a highly D–A‐accumulated (14D + 4A) non‐statistical triple‐wall nanotube [(Zn 2+ ) 8 ( L D ) 14 ( L A ) 4 ] driven by linkages with eight zinc ions (Zn 2+ ) is fabricated ( L D and L A are anthracene‐ and anthraquinone‐based ditopic ligands, respectively). The absolute D and A positions are successfully determined by x‐ray diffraction analysis on a single crystal of (Zn 2+ ) 8 ( L D ) 14 ( L A ) 4 , realizing their nanotubular arrangements with a non‐statistical D–A sequence. The four L A ligands are located at the inner positions of the nanotube and undergo CT interactions with the outer four L D ligands, and the other 10 L D ligands form dimers [( L D ) 2 ] through π‐stacking or excitonic interactions between the anthracene rings. The intra‐tube L D / L A CT interactions produce a CT absorption band at long wavelength, enabling the (Zn 2+ ) 8 ( L D ) 14 ( L A ) 4 nanotube to absorb long‐wavelength green light through CT excitation ( L D / L A + h ν (CT) → L D •+ / L A •– ). Long‐wavelength light excitation provides a bright red excimer emission from the anthracene dimer units [( L D ) 2 * ]. This is most probably arising from flows of the low‐energy photon‐generated CT excitons.