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A new type of electronic interaction which couples two angular momenta, i.e. the angular momentum of a localized 4f system (J) and an orbital angular momentum generated in a cyclic π conjugated system by irradiation with a circularly-polarized light, has been identified in a lanthanide single molecule magnet.

Magnetic f-π interactions between localized 4f-electrons and itinerant π-electrons have been observed in a single crystal of bisphthalocyaninato yttrium(iii)/terbium(iii) tetrafluoroborate ([Pc2Y0.95Tb0.05][BF4]) by measuring electrical conductivity of the crystal in the presence of an external magnetic field.

A series of fourteen heteroleptic (phthalocyaninato)(porphyrinato) rare earth(III) double-decker complexes, [MIII(Pc)(TClPP)] [M=Y, La–Lu except Ce and Pm; Pc=phthalocyaninate; TClPP=meso-tetrakis(4-chlorophenyl)porphyrinate] has been prepared by base-promoted cyclization of phthalonitrile on the corresponding [MIII(TClPP)(acac)] (acac=acetylacetonate) as the template in refluxing n-octanol. The yields are highest for the mid-lanthanides, which have the optimum size to balance the stabilization due to π-π interactions and the destabilization due to axial compression of the two π systems. The whole series of double-decker complexes has been characterized by elemental analysis and a wide range of spectroscopic methods. The molecular structure of [GdIII(Pc)(TClPP)] has also been determined. All the electronic absorption bands are dependent on the size of the metal center, suggesting that all the transitions involve molecular orbitals with contributions from both Pc and TClPP ligands. This has been supported by a systematic investigation of the electrochemical properties of the whole series of complexes. All these studies indicate that there are substantial π-π interactions and the hole is mainly localized at the Pc ligand.

A sterically congested tetraphenyl-substituted dibenzo-tetraaza-isobacteriochlorinato nickel derivative unexpectedly reacts with methanol at room temperature to release internal molecular strains, leading to the formation of a ligand having a skeleton bearing two cis-methoxy substituents.

Molecular self-assembly of porphyrin derivatives formed with intermolecular hydrogen bonding on the surface of Au(111) electrode in acidic solution can be controlled by varying the number of peripheral carboxy groups and the applied electrochemical potential.

A novel μ-oxo hetero dimer of silicon phthalocyanine and silicon naphthalocyanine was synthesized. Its unique optical properties, such as a single Q band, which is unusual for hetero dimer species, and solvatochromic behavior, were revealed to be better interpreted by taking interchromophore interactions into consideration.

A reaction of 1,2-dicyanobenzene and lithium methoxide at 70 °C in methanol yielded the half-phthalocyanine intermediate, which coordinates to a cadmium(II) ion in the subsequent reaction step to give the first example of a six-coordinate phthalocyanine analogue containing a divalent metal ion at the center.

Two terbium ions in a triple-decker complex (Pc)Tb(Pc)Tb(T(p-OMe)PP) (Pc = phthalocyaninato, T(p-OMe)PP = tetra-p-methoxyphenylporphyrinato) have shown sharply different magnetic behaviours depending on symmetry of the coordination polyhedron. The fast quantum tunnelling relaxation process in a square-prismatic site has been revealed to be hindered by magnetic-dipolar coupling between the f-electronic systems.

Homo and heteronuclear quadruple-decker phthalocyanine tetramers containing Y(3+) and/or magnetically anisotropic lanthanide ions such as Tb(3+), Dy(3+), and Er(3+) have been synthesized, and their magnetic properties have been elucidated, giving clear evidence of the long-range interactions between two f-electronic centers.

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.

Electroabsorption spectra of electron donating butyloxy- (OBu) or electron withdrawing butylsulfonyl (SO(2)Bu)-substituted tribenzotetraazachlorin (TBTAC)-C(60) conjugates (1 and 2, respectively) have demonstrated that significant change of the molecular polarizability is associated with the photoexcitation of 1 in the lower energy region, while that in the higher energy region is comparable with the corresponding band of 2, although the pi-aromatic structures of 1 and 2 are identical to each other, being consistent with the previously reported result of the DFT calculations.

A subphthalocyanine (SubPc) dimer linked by racemic 1,1'-binaphth-2,2'-dioxy (BINOL), 1, has been synthesized and characterized by 1- and 2-D 1H NMR, high resolution mass spectrometry (FAB), X-ray crystallography and electronic absorption spectroscopy. Additionally, the dimer derived from optically-active (R)-(+)-BINOL, 2, has been made and studied using CD and MCD spectroscopies.