- X-ray photoelectron spectroscopy of phthalocyanine compounds
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X-ray photoelectron spectra arising from carbon 1s, nitrogen 1s, and iron 2p and 3s levels of metal-free phthalocyanine (H2Pc), iron (II) phthalocyanine , and several derivatives of ironaphthalocyanine (FePcL), where L = Cl, NO and FePcL2, whe
- Ouedraogo, G. V.,Benlian, D.,Porte, L.
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- Oxochromium compounds. 1. Synthesis and properties of μ-oxo chromium-iron porphyrin and phthalocyanine compounds
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The reaction between CrIVO(P) and FeII(P′) leads to the formation of μ-oxo heterobinuclear complexes (P)CrOFe(P′) where P and P′ represent dianions of porphyrins that may be the same or different. [Abbreviations for the dianions of 5,10,15,20-tetraarylporphyrins: TPP, tetraphenylporphyrin; TTP, tetra-p-tolylporphyrin; TMP, tetrakis(p-methoxyphenyl)porphyrin; TFP, tetrakis(p-fluorophenyl)porphyrin; TCP, tetrakis(p-chlorophenyl)porphyrin; TXP, tetra-3,5-xylylporphyrin; OEP, the dianion of 2,3,7,8,12,13,17,18-octaethylporphyrin; Pc, the dianion of the phthalocyanine molecule.] The complexes react with heterocyclic Lewis bases, and these coordinate to Cr only. The visible, infrared, 1H NMR, and Mo?ssbauer spectra are reported for the compounds. The variation of magnetic susceptibility with temperature down to 4.2 K is interpreted in terms of strong antiferromagnetic coupling between Cr(III) (S = 3/2) and Fe(III) (S = 5/2) centers with J values in the range -130 to -150 cm-1. Zero field splitting effects are important at low temperatures. The reaction of CrO(TPP) with FeII(Pc) forms an analogous μ-oxo complex having porphyrin and phthalocyanine groups attached to Cr(III) and Fe(III), respectively.
- Liston, David J.,Kennedy, Brendan J.,Murray, Keith S.,West, Bruce O.
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p. 1561 - 1567
(2008/10/08)
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- Iron(III)phthalocyanines: Preparation and Spectroscopic Characterisation of (-) (R = H, CH3, C2H5, (CH3)2CH, (CH3)3C), FePc(-2))2O and FeXPc(-2) (X = F, Cl, Br, I)
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The preparation of bis-hydroxophthalocyaninatoferrate(III) and of some of the bis-alkoxo-analogues is described.In the presence of a small excess of OR(-) (R = H, CH3, C2H5, (CH3)2CH, (CH3)3C) these complexes are stable in most common non-polar solvents and can be isolated as analytically pure bis-triphenylphosphiniminium-(PNP)-salts.Solutions of these complexes react immediately with water and acids.Thus hydrolysis is an easy way to prepare μ-oxo-bis-phthalocyaninatoiron(III).The reaction with mineral acids HX (X = F, Cl, Br, I) precipitates the pure pentacoordinated halogenophthalocyaninatoiron(III).The electronic absorption spectra have been measured.Besides the typical innerligand ?-?*-transitions additional bands are observed at ca. 11,5 kK (CT 1) and ca. 20 kK (CT 2).These bands are of medium intensity only for FeXPc(-2) (X = Cl, Br, I) especially in the solid state spectra and are probably associated with ligand-to-metal-charge-transfer(CT)-transitions mainly of the Pc -> Fe-type but partially mixed with X -> Fe.CT 1 and CT 2 are assigned to (a1)? -> (e,a1)d respectively.This is confirmed by the resonance Raman spectra.On excitation within the range of the CT 2 electronic transition some in-plane stretching- (1595 and 1550 cm-1) and out-of-plane deformation vibrations (350 and 290 cm-1) of the macrocycle as well as the Fe-X-stretching vibrations are resonance Raman enhanced.Combination bands of Fe-X- with Pc-vibrations give strong evidence for coordination of the halide to an axial position of the iron centre.As expected for C4v point symmetry the Fe-X vibrations are IR active, too (ν(Fe-X) for X = F: 475; Cl: 303; Br: 221; I: 193 cm-1).The Fe-O stretching vibration (a1g) is only observed in the resonance Raman spectrum of PNP at 495 cm-1.As a consequence of the strong antiferromagnetic coupling the IR and resonance Raman spectra of (FePc(-2))2O resemble those of closed shell ions.The IR absorption at 822 cm-1 is assigned to the antisymmetric (a2u) (Fe-O-Fe) deformation mode. - Keywords: Bis-hydroxo-iron(III)phthalocyanine, Vibrational Spectra, UV-VIS Spectra, Iron(III)phthalocyanines
- Kalz, W.,Homborg, H.
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p. 470 - 484
(2007/10/02)
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