Hybrid Orbital Deformation (HOD) Effect and Spectral Red-Shift Property of Nonplanar porphyrin

A series of 5,15-meso,meso-strapped nonplanar porphyrins with different degrees of ruffling distortion, as a model system, have been synthesized and characterized. The spectral red-shift of the nonplanar porphyrins was experimentally demonstrated to mainly originate from the hybrid orbital deformation (HOD) effect due to the distortion in the tetrapyrrole macrocycle, which confirmed previous explanations to the red-shift phenomenon.