Near-infrared-excited FT-Raman spectra of covalently linked porphyrin-nitrobenzene compounds

FT-Raman spectra for three covalently linked porphyrin-nitrobenzene compounds have been acquired using near-infrared (1064 nm) excitation. The relative intensities of several Raman bands are found to depend on the substitution pattern of the porphyrin macrocycle and on whether the covalent linkage is through single or double bonds. Spectra are interpreted as indicating that ground-state electronic coupling between the porphyrin and nitrobenzene moieties occurs by way of a through-bond mechanism