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A copper phthalocyanine with four crown ether voids has been synthesized; its high tendency towards aggregation, especially K+-induced aggregation, which enables the phthalocyanine to be used as a colorimetric reagent, is reported.

The octacarboxyl gallium (GaPcC) and metal-free (H2PcC) phthalocyanines were prepared using the carboxyl as the peripheral substituent. The carboxylation improves the intracellular delivery of these two PcCs into KB and QGY cancer cells as compared to that of sulfonated aluminum phthalocyanines (AlPcS), a popularly used photosensitizer (PS). Moreover, GaPcC maintains high photoproduction of singlet oxygen. With a short incubation time of 3 hours, GaPcC accumulates sufficiently in both KB and QGY cells and improves photodynamic therapy (PDT) by effectively killing these cancer cells. AlPcS and H2PcC show much lower PDT effects under the same conditions, because AlPcS have a slow cellular uptake rate resulting in a low cellular amount and the ability of H2PcC to produce 1O2 is low. Carboxylation is a promising way to prepare water-soluble metal phthalocyanines (MPcCs) and facilitates the cellular uptake of MPcCs for PDT improvement.

A new measuring method of the pinning potential, Uc, for thermally activated flux creep is proposed. By this type of resistive measurements, we can obtain the observed data of Uc even in the low field region, where the direct comparison with the observed data from the magnetization measurements is possible. The observed results of Uc by the present resistive measurements for a c-axis oriented CVD film of YBa2Cu3O7 at 77.3K were 0.05eV at 3T and 0.07eV at 2T, while Uc from the magnetization measurement was 0.09eV at 1T. The present results clearly resolved a strange puzzle that the values of Uc, which have been inferred from the observed data of the existing resitive method at higher temperatures by using the Malozemoff type of temperature dependence of Uc, are usually more than ten times larger than those obtained from the magnetization measurements. It is also pointed out that the use of Fujiyoshi type of temperature dependence of Uc leads to the values of Uc with the same order of magnitude as those form the magnetization measurements.

Resonance Raman spectroscopy of small diameter (below 1.2 nm) single‐wall carbon nanotubes (SWCNT) is presented. The diameter and chirality dependent many‐body corrections to the tight binding based Kataura plot are discussed. The radial breathing modes also show small chirality dependence, giving evidence for the deviations of the small nanotube diameters from the ideal folded graphene structure. The use of spectroscopy for the characterization of small environmental effects and the (n,m) population on HiPco and CoMoCAT SWNT samples is pointed out. The richness of the intermediate frequency modes is highlighted.

We report the first MCD spectral.data for free base corrolazine and a transition metal corrolazine complex. A detailed analysis of the MCD and UV-visible absorption spectroscopy of these compounds and phosphorous corrolazine and triazatetrabenzocorroles is carried out based on the results of TD-DFT calculations and an application of Michl's perimeter model.

We present results on the magnetic field-induced martensitic phase transformation in Ni2MnGa. The experiments were carried out in a wide temperature range from 10 to 300 K and in magnetic fields up to 5 T. Two successive anomalies in the temperature dependence of main (2 2 0) peak width, corresponding to martensitic transition temperature (Tm) and premartensitic transition temperature (Tp), respectively, are detected. It is found that Tm increases and Tp decreases with applying magnetic fields up to 2 T, and then the transition temperatures do not change in fields up to 5 T.

(18-Crown-6)-linked binuclear phthalocyanines have been synthesized and their electronic absorption and magnetic circular dichroism spectra have been recorded. Neither alkaline nor alkaline earth metals have affected the spectra

We present the crystal structure of pcFe(4-methylpiperidine)2 as a first example of a low-spin iron(II) phthalocyanine (pc) complex bis-axially coordinated by aliphatic amines. It is shown that electronic rather than steric effects are responsible for the elongation of the Fe−N(axial) bond in pcFeL2 complexes. Using density functional theory, the electronic structures as well as Mossbauer isomer shifts and quadrupole splittings have been investigated for a large number of pcFeL2 and pcFeL1L2 complexes, in which the axial ligands have varying electronic and steric properties. The electron charge densities and electric field gradients at the iron ion were evaluated using a locally dense basis approach with Wachters’ all-electron basis set for the iron ion, the 6-311++G(2d) basis set for atoms directly bonded to the iron ion, the 6-31G(d) basis set for atoms two bonds away from the iron ion, and the 3-21G* basis set for all other atoms. A good correlation between the theoretical and experimental isomer shifts and quadrupole splittings has been observed for all the complexes tested. It has also been shown that the proposed model for the calculation of Mossbauer spectral parameters is adequate for the evaluation of the axial ligand conformation in cases of conformational flexibility in pcFeL2 complexes.

A highly deformed [1,4,8,11,15,18,22,25-octaphenylphthalo-cyaninato(2-)]iron(II) has been synthesized, and found to show absorption bands which may be assigned to metal-to-ligand charge transfer (MLCT) transitions in the near-IR region beyond the Q-band in pyridine, due to lowering of molecular symmetry to D2d from D4h symmetry of normal metallophthalocyanines.

Induced circular dichroism has revealed that β-cyclodextrin accommodates one pyrene molecule with axial inclusion but that γ-cyclodextrin includes two pyrene molecules with S-helicity.

U.v. absorption and induced circular dichroism studies have indicated a new type of inclusion behaviour (‘lid-type’) in cyclodextrin–arene 1 : 1 host–guest complexes exemplified by the pyrene-1,3,6,8-tetrasulphonate–β-cyclodextrin complex.

Induced circular dichroism (ICD) has suggested that γ-cyclodextrin (γ-CDx) accommodates two molecules of naphthalene and its derivatives with nearly axial inclusion but that it includes two Acridine Orange (AO) molecules with S-helicity.

Magnetic circular dichroism (MCD) spectra in the near-infrared region reported first for oxidized cytochrome c in its neutral (pH 5.58), alkaline (pH 11.62), and acidic (pH 1.88) forms exhibit temperature dependence, indicating that they are composed of Faraday C terms, except for the acidic form. The relation between the near-infrared MCD and the heme vicinity is discussed in terms of the structures for the heme chromophore of cytochromec.

The thermally activated behavior in the resistive transition and the relaxation phenomenon of the dc magnetization of Y Ba Cu O films have been investigated in magnetic fields up to 25 T. The behavior of the electrical resistance is not consistent with the simple flux creep model based on the Lorentz force. Moreover, the activation energy estimated from the resistance measurements is about one order larger than that from the magnetic relaxation.

Electronic structures of iron in hemoproteins have close correlation with their reactivity. Many physicochemical techniques have been applied to hemoproteins to elucidate electronic structures of heme irons. However, conclusive experimental determination of the electronic structures of low spin iron(II) heme, especially oxygenated hemes, waits for further examinations. In order to determine the electronic structures of the hemes directly from the view point of their ground state, we have started 57 Fe NMR studies of heme complexes in succession to our MCD [1] and ab initio calculation [2] on the heme complexes. 57 Fe NMR spectra were obtained by using steady-state free precession and the quadriga Fourier transform technique [3–5]. First, T 1 values of 57 Fe nuclei have been estimated for Fe(CO) 5 and ferrocene with natural abundance of 57 Fe. 15 N-enriched, α,β,γ,δ- meso -tetra-phenylporphine (TPP) and α,β,γ,δ- meso-p -tolylporphine (TTP) were prepared from 15 N-labeled pyrrole (CEA Saclay, 95% enrichment), and benzaldehyde or p -tolylaldehyde by the usual method [6]. Incorporation of 57 Fe (Spire, 95.45% enrichment) was accomplished by Rothemund's method [7]. Bis-pyridine and bis-pyrrolidine complexes of [ 15 N, 57 Fe)-TTP and [ 15 N, 57 FE]-TTP with Fe(II) low spin state were prepared by a conventional method [8]. The 57 Fe NMR spectra recorded on a Bruker CXP-300 NMR spectrometer incorporated with a Bruker 57 Fe probe (using 15 mm sample tube), can be tuned between 10.2 and 9.2 MHz. The chemical shift values of the bis-pyridine complex of [ 15 N, 57 Fe]-TTP, of the bis-pyrrolidine complex of [ 15 N, 57 Fe]-TTP, of K 4 [Fe(CN) 6 ] and of ferrocene are 7341, 7258, 2495, and 1531 ppm low field from that of Fe(CO) 5 as a reference. The variation of chemical shifts of various iron(II) complexes will be discussed in terms of the d–d energy splitting in a similar way to that of 59 Co-complexes [9].

The specific heat, C, of samples of both orthorhombic and tetragonal phases in YBa 2 Cu 3 O 7 system has been measured in the temperature range from 1.5 to 10 K and in magnetic fields up 3 O 7 6T. The zero field behaviors are not so different from the data reported by many authors. The specific heat in H = 6 T decreases rapidly with decreasing temperature below about 3 K and attains to a smaller value than the coefficient of the T-linear term (H= 0). It is pointed out that one must carefully discuss about the electronic contribution to the specific heat of the YBa 2 Cu 3 O 7−δ system.

Monomeric and dimeric species of phthalocyanines with four, 15-crown-5-ether (1,4,7,10,13-pentaoxacyclopentadecane) voids at the 2,3 positions (ML)(where M = H2, Cu, Zn, Ni, or Co), have been studied using optical absorption and magnetic circular dichroism (m.c.d.) spectroscopies. The ready solubility of these crown ether-substituted complexes in chloroform allows the measurement of spectral data over a wide wavelength range. In particular, absorption and m.c.d. data are reported for H2L between 250 and 750 nm. The contribution by individual bands to the absorption and m.c.d. spectral envelopes measured for the monomeric and dimeric species of H2L and NiL, has been determined using deconvolution calculations carried out on pairs of related absorption and m.c.d. spectra. M.c.d. A terms have been used to identify the O, B1, B2, and Nπ→π* degenerate transitions in the spectra of the monomer of NiL, at 14 946 cm–1(669 nm) in the visible region, and at 24 398 (410), 31 414 (318), and 36 286 cm–1(276 nm) in the u.v. region. The deconvolution calculations were also used to find the pairs of bands that arise from the exciton splittings in the Q and B bands of the cofacial dimers. In the spectra of the dimer of NiL, two degenerate bands are required to fit the observed envelope in the Q-band region [at 14 887 (672) and 15 832 cm–1(632 nm)], which indicates that the splitting is ca. 950 cm–1, while the pair of B bands are separated by ca. 2 180 cm–1. The deconvolution of the spectra of the H2L complex gives a value of 1 925 cm–1 for the separation of the two components in the B band region.

Symmetrically tetra-substituted phthalocyanines with four quinone or porphyrin units attached have been synthesised and some of their spectroscopic properties are reported.

The formation of a charge-transfer complex between sodium α-naphthylacetate and picric acid was promoted markedly by γ-cyclodextrin but not-significantly by β-cyclodextrin.

The synthesis, characterisation, and intramolecular interactions of a metal-free planar binuclear phthalocyanine and its cobalt derivatives are described.

Mossbauer and e.s.r. spectroscopy have revealed that 2,3,9,10,16,17,23,24-octacarboxy-(1), 2,9,16,23-tetracarboxy-(2), and 2,9 (or 10)- and 2,16 (or 17)-bis(3′,4′-dicarboxybenzoyl)-phthalocyaninatoiron (3) are mixtures of high-spin iron (III) and low-spin iron (III) complexes and that intermediate-spin species may be present in (2) in the solid state. However, the low-spin component disappears when the phthalocyanines are immobilized on poly(styrene). The properties of these compounds in solution are described on the basis of e.s.r., m.c.d., and u.v. spectroscopy.

Magnetic susceptibility, e.s.r., u.v. absorption, and m.c.d. spectroscopy have revealed that 4,4′,4″,4‴-tetra-decyloxycarbonylphthalocyaninatoiron (1), its monoimidazole adduct (2), and its di-imidazole adduct (3) are high-spin iron (III), low-spin iron (III), and low-spin iron (II) complexes, respectively.

A copper phthalocyanine with four crown ether voids has been synthesized; its high tendency towards aggregation, especially K+-induced aggregation, which enables the phthalocyanine to be used as a colorimetric reagent, is reported.

4,4′,4″,4‴-Tetradecyloxycarbonylphthalocyaninatoiron(III)(1) reacts with imidazole to form its mono-(2) and subsequently its di-imidazole (3) complexes with formation constants of >108 and 108 dm3 mol–1 in dichloromethane at 20 °C, respectively.