Vibrational spectroscopic characteristics of phthalocyanine and naphthalocyanine in sandwich‐type phthalocyaninato and porphyrinato rare earth complexes. Part 11—Raman spectroscopic characteristics of phthalocyanine in mixed [tetrakis(4‐chlorophenyl)porphyrinato](phthalocyaninato) rare earth double‐deckers

Abstract

Abstract Raman spectroscopic data in the range 500–1800 cm −1 for a series of 15 mixed [tetrakis(4‐chlorophenyl)porphyrinato](phthalocyaninato) double‐decker complexes with tervalent rare earths M III (TClPP)(Pc) (M = Y, LaLu except Ce and Pm) and intermediate‐valent cerium Ce(TClPP)(Pc) were collected using laser excitation sources emitting at 632.8 and 785 nm. Comparison with the Raman spectra of corresponding bis(phthalocyaninato) rare earths reveals that the Raman characteristics of mixed‐ring double‐deckers are dominated by the phthalocyaninato‐metal fragment M(Pc) and phthalocyanine exists as the monoradical anion Pc •− in M III (TClPP)(Pc) and the dianion Pc 2− in Ce(TClPP)(Pc), respectively. With excitation at 632.8 nm, which is in close resonance with the main Q absorption band of the phthalocyanine ligand, a typical Raman marker band of the monoanion radical Pc •− was observed at 1512–1519 cm −1 as a weak band resulting from the coupling of pyrrole CC and aza CN stretchings. For Ce(TClPP)(Pc), a strong band at 1492 cm −1 with contributions from both pyrrole CC and aza CN stretchings and also isoindole stretching was the marker Raman band of Pc 2− . When excited with laser radiation of 785 nm, which is far away from the main Q absorption band of the phthalocyanine ligand, the marker Raman band of Pc •− in M III (TClPP)(Pc) is observed at 1495–1514 cm −1 and of Pc 2− in Ce(TClPP)(Pc) at 1511 cm −1 as a strong band. Copyright © 2004 John Wiley & Sons, Ltd.