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The electronic absorption and magnetic circular dichroism spectral data of a phtalocyanine dicopper complex that is deduced to be very planar and to share a common benzene ring is studied by band deconvolution analysis. The results are compared with those of the molecular orbital calculations and it is reported that the band deconvolution analysis is in good agreement with those of the PPP calculations.

Absorption spectral changes observed during sodium mirror reduction of tribenzotetraazachlorin-fullerene (TBTAC-C60) conjugates have clarified that electronic communication between the TBTAC and C60 moieties is switched off upon reduction of the conjugates. Spectroscopy has suggested that the anionic species retains its aromatic character. [ABSTRACT FROM AUTHOR]

Magnetic relaxations arising from spin-phonon interactions for a magnetically diluted double-decker terbium phthalocyanine single molecule magnet, dil1, in the nonthermally activated temperature range have been investigated. While the relaxation time, τ, is independent of the external static magnetic field, Hdc, in the high temperature range, where linear relationships between -ln τ and T-1 are observed in the Arrhenius plot, magnetic field dependences for τ are observed in the lower temperature range. The τ-1 vs Hdc plot at 12 K fits the quadric curve when Hdc < 12 kOe, while linear relationships are observed in the τ-1 vs T plots in the temperature range of 12-20 K. These results indicate that the direct process is the dominant magnetic relaxation pathway in the nonthermally activated temperature range, while the contribution from the Raman process, if any, is not observable. We emphasize in this paper that the contribution from the thermal relaxation processes and the quantum tunneling of magnetizations (QTMs) to the experimentally observed magnetic relaxations must be evaluated carefully in order to avoid confusion between the thermal and quantum-mechanical relaxation pathways. [ABSTRACT FROM AUTHOR]

A novel platinum-based macrocycle, iron(ii) tetrakis(diaquaplatinum)octacarboxyphthalocyanine (PtFeOCPc), was synthesised and characterised. The heterogeneous electron transfer and electrocatalytic properties of this functional material towards the oxidation of formic acid have been explored on a graphite electrode platform pre-modified with or without acid-functionalised multi-walled carbon nanotubes (MWCNTs). We prove that PtFeOCPc supported on a MWCNT platform (MWCNT–PtFeOCPc) exhibits enhanced electrochemical response in terms of (i) electron transfer towards outer-sphere redox probe, (ii) catalytic rate constant, and (iii) tolerance towards CO poisoning during formic acid oxidation. The results clearly suggest that the MWCNT–PtFeOCPc is a promising platform for potential application as an electrocatalyst for direct formic acid fuel cell. [ABSTRACT FROM AUTHOR]

The reaction of phthalonitrile and lithium methoxide at 70 °C in methanol yields a half-phthalocyanine intermediate, which coordinates to a zinc(II) ion in a subsequent reaction step to afford a novel five-coordinate zinc phthalocyanine analogue 2, having axially coordinating diiminoisoindole and methoxy moieties bonded at diagonal positions of the pyrrole α-carbons. Although the chromatographic isolation of 2 is problematic, its crystal structure has been determined unambiguously. The importance of the effective ionic radius of the zinc(II) ion for the resultant molecular structures is discussed. [ABSTRACT FROM AUTHOR]

A tribenzotetraazachlorin (TBTAC)-C60conjugate having three 15-crown-5 units as substituents, 1, has been synthesized, and the electronic and supramolecular structure modulations in the presence of Na+or K+have been elucidated by means of massmetric and spectroscopic techniques. [ABSTRACT FROM AUTHOR]