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) orphyrinato(phthalocyaninato) rare earth double-deckers

摘要

Raman spectroscopic data in the range of 500-1800 cm-1 for a series of 15 mixed [tetrakis(4-chlorophenyl)porphyrinato](phthalocyaninato) double-decker complexes with tervalent rare earths MIII(TClPP)(Pc) (M = Y, La...Lu except Ce and Pm) and intermediate-valent cerium Ce(TClPP)(Pc) have been 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 monoradical anion Pc•- in MIII(TClPP)(Pc) and dianion Pc2- in Ce(TClPP)(Pc), respectively. Under excitation at 632.8 nm that is in close resonance with the main Q absorption band of phthalocyanine ligand, 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 as well as the isoindole stretching was the marker Raman band of Pc2-. 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 MIII(TClPP)(Pc) is observed at 1495-1514 cm-1 and of Pc2- in Ce(TClPP)(Pc) at 1511 cm-1 as a strong band.