Raman spectroscopic characteristics of phthalocyanine and naphthalocyanine in sandwich-type phthalocyaninato and porphyrinato rare earth complexes. Part 3. The effect of rare earth ionic size on the Raman characteristics of naphthalocyanine in bis(na

摘要

Raman spectroscopic data of a series of 13 sandwich double-decker bis(naphthalocyaninato) rare earth complexes M(2,3-Nc*)(2) [M = (CeLu)-Lu-... except Nd and Pm, Y; Nc* = Nc(t Bu)(4)] were collected using laser excitation sources emitting at 632.8 and 785 nm and systematically compared. The Raman characteristics for substituted naphthalocyaninato monoradical anion Nc*(.-) under these two laser excitations are thus comparatively described. The strongly enhanced Raman band at approximately 1592 cm(-1) which is assigned to the naphthalene stretches of the Nc ring, is a typical feature of the monoanion radical, Nc*(.-) under excitation with the 632.8 nm laser line. With laser excitation at 785 nm, which is nearly coincident with the Q band absorption of bis(naphthalocyaninato) rare earth complexes, the band at 1512-1530 cm(-1) due to the C=N (aza group) stretch is a good Raman marker band for the naphthalocyanine anion Nc*(.-). This band and the Nc breathings, naphthalene stretchings, isoindole stretchings, and coupling of pyrrole C=C ring and aza C=N stretches all shift to higher frequency with decreasing ionic radius (the rare earth contraction). (C) 2002 Elsevier Science Ltd. All rights reserved. [References: 59]