oC and heat of vaporization, ΔH approximately -23 kcal/mole. Vacuum uv spectra of H2OEP and Cu(OEP) down to 145 nm are presented which show absorption across the entire range with more intense bands at 194 nm (51,500 cm-1), 162 (62,000), and 150 (75,000) and no evidence of Rydberg structure. The vapors of the Mn and Fe complexes show unusually different spectra from their solutions. Similar spectra to the vapor are obtained when solutions of MnAc(OEP) and FeCl(OEP) are subjected to electrolytic reduction, suggesting that the vapor species are the reduced forms. Spectra of H2OEP, Cu(OEP) and MnCl(OEP) in silicone oil at 300 oC are given. Broadening comparable to the vapor spectra is observed. Also the visible bands shift to the red while the Soret band shows no change. ">

Pub No:
17
Title:
Porphyrins XVI. Vapor Absorption Spectra and Redox Reactions: Octaalkylporphins
Authors:
Edwards, L., David Dolphin, and Gouterman, M.
Journal:
Journal of Molecular Spectroscopy
Year:
1970
Pages:
35(1), 90-109
Abstract:
Vapor absorption spectra at 800-200 nm are given for free base octaethylporphin (H2OEP), Mg etioporphyrin-I, VO(OEP), Co(OEP), Ni(OEP), Zn(OEP), Pd(OEP), MnCl(OEP), MnAc(OEP), and FeCl(OEP). Electronic bands Q, B, N, and M characteristic of the ring are found in the regions 570 nm (17,500 cm-1), 390 (25,500), 325 (30,800), and 213 (47,000), respectively. All compounds show at least one "extra" band between N and M of variable intensity and energy. Spectroscopic measurements gave for all compounds show p of approximately 0.1 torr at 330 oC and heat of vaporization, ΔH approximately -23 kcal/mole. Vacuum uv spectra of H2OEP and Cu(OEP) down to 145 nm are presented which show absorption across the entire range with more intense bands at 194 nm (51,500 cm-1), 162 (62,000), and 150 (75,000) and no evidence of Rydberg structure. The vapors of the Mn and Fe complexes show unusually different spectra from their solutions. Similar spectra to the vapor are obtained when solutions of MnAc(OEP) and FeCl(OEP) are subjected to electrolytic reduction, suggesting that the vapor species are the reduced forms. Spectra of H2OEP, Cu(OEP) and MnCl(OEP) in silicone oil at 300 oC are given. Broadening comparable to the vapor spectra is observed. Also the visible bands shift to the red while the Soret band shows no change.

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