Single site electronic spectroscopy of free base octaethylporphyrin, octaethychlorin and their diacids in n-octane at 298 K and 7 K

Single site fluorescence and absorption spectra of free base octaethylporphyrin, octaethylchlorin and their respective diacids in n-octane at 298 K and 7 K are reported. Vibrational frequencies associated with the ground and excited states were determined from the spectra. All of these moieties exhibit well defined and narrow spectral features, with the exception of the octaethylchlorin diacid; it gives broad spectral bands even at 7 K. Respective Q and B origins were also identified.