Self-complementary Structure of Bisporphyrin Dimer.

The crystal structure of a bisporphyrin cleft molecule revealed that the head-to-head dimeric structure is directed by the intermolecular self-complementary hydrogen-bonding interactions of amide groups and π-π stacking interactions. The UV/ Vis absorption spectrum of the homodimeric structure in the solid-state resulted in a broad Soret band. Time-dependent density functional theory (TD-DFT) calculation of the dimer indicated that an intra- and intermolecular charge transfer transition as well as a π-π* transition were responsible for the observed broad Soret band. [ABSTRACT FROM AUTHOR]