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Neutral double-decker radical lutetium(III) diphthalocyanine with eight crown ether substituents bound through oxymethyl bridges has been synthesized from 1-[(benzo-15-crown-5)-4′-yl]oxymethyl-3,4-dicyanobenzene and lutetium(III) acetate. The ESR spectrum confirmed the radical nature of the complex.

Starting from 1,2-naphthalocyanine lutetium acetate (1,2-NcLuOAc) the unsymmetrical lutetium phthalo(naphthalo)cyanine (1,2-NcLuPc) has been synthesized and characterized by optical absorption spectra and fast atom bombardment (FAB) mass spectrometry. 1,2-Naphthalocyanine shows several geometrical isomers, both the mixture (noted Nc^∑) and one of them (Nc^Cs) have been used for forming the corresponding bismacrocycles. As a result the first racemic mixture of a chiral unsubstituted phthalo(naphthalo)cyanine complex has been synthesized and characterized.

Spectroscopic properties of discotic liquid crystalline bis[octakis(3,4-dialkoxyphenoxy)-phthalocyaninato]lutetium(III) complexes, {[(C_nO)₂PhO]₈Pc}₂Lu (n = 12: 2a and n = 13: 2b), were investigated by recording electronic absorption spectra in the region of 250-2600 nm under three different conditions; solution, mixed solvent solutions, and a thin film at various temperatures. An intermolecular charge transfer (CT) band was found at about 2000-2100 nm both for the n-hexane solution and the thin film. It was established for the first time from the solvent-polarity-dependent and temperature-dependent electronic absorption spectra that the intermolecular CT band is attributable to molecular aggregation.

Tris[tetra(15-crown-5)phthalocyaninato]dilutetium(III) (R₄Pc)₃Lu₂, whose structure had been confirmed earlier by X-ray analysis, was further examined by physicochemical studies. The redox properties of this complex were investigated by cyclic voltammetry. The spectroelectrochemical study of this compound has been performed for the first time. Based on the results obtained and analysis of literature data, an electrochemical criterion related to double- and triple-decker structure of lanthanide phthalocyanines has been proposed. IR and ¹H NMR data are also reported.

The conversion of compound 1 [2,4,6-tris(2-oxaphthalonitrile)-s-triazine] into its isoindoline derivative of 2,4,6-tris[2-oxa(1,3-hexaimino isoindoline)]-s-triazine 2 was accomplished by bubbling ammonia gas through a solution in methanol in the presence of sodium methoxide. The cyclization of two different isoindoline derivatives namely, compound 2 and 4,5-bis(hexylthio)-1,2-diimino-isoindoline 3 with lutetium(III) acetate, [Lu(OAc)₃] in refluxed DMF by the method of statistically mixed condensation gave trimeric trilutetium phthalocyanine [(LuOAc)₃(Pc)₃]4. [Lu₃(Pc)₆]5 has been synthesized in situ by the reaction of phthalocyanine 4 and three equivalents of dilithium octakis-hexylsulfanyl phthalocyanine in amyl alcohol.

Sandwich-type complex based on tetradiazepinoporphyrazine ligand — bis{tetrakis(5,7-di(4-tert-butylphenyl)-6H-1,4-diazepino)[2,3-b,g,l,q]porphyrazinato}lutetium — was synthesized for the first time. The structure of the compound has been confirmed by UV-vis/NIR, ¹H NMR spectroscopy, and MALDI-TOF mass spectrometry data. The introduction of annulated diazepine heterocycles to porphyrazine molecule significantly changes macrocycle reactivity and results in sandwich-type complex under conditions used for the selective synthesis of lanthanide(III) monophthalocyanines.

The DANCE¹ (Detector for Advanced Neutron Capture Experiments) array at LANSCE spallation neutron source in Los Alamos has been used to obtain the neutron radiative capture cross sections for ¹⁷⁵Lu and ¹⁷⁶Lu with neutron energies from thermal up to 100 keV. Both isotopes are of current interest for the nucleosynthesis s-process.^2,3 Three targets were used to perform these measurements. One was natural Lu foil of 31 mg/cm² and the other two were isotope-enriched targets of ¹⁷⁵Lu and ¹⁷⁶Lu. Firstly, the cross sections were obtained by normalizing yield to a well-known cross section at the thermal neutron energy. Now, we want to obtain absolute cross sections of radiative capture through a precise neutron flux determination, an accurate target mass measurement and an efficiency determination of the DANCE array.

Neutron super-elastic scattering, also called neutron inelastic acceleration (INNA), occurs during the collision of a neutron with an excited nucleus. In this reaction, the nucleus could partly transfer its excitation energy to the scattered neutron. The effect of this neutron induced de-excitation is known in nuclear astrophysics to take place in the s-process nucleosynthesis.¹ Here, we report on the INNA cross section measurement, for the long-lived metastable state of ¹⁷⁷Lu, which was achieved using a direct method. High-energy neutrons have been detected using a specially designed setup placed on a cold neutron beam extracted from the ORPHEE reactor in Saclay. The measured value of 146±19 b for the INNA cross section in the ORPHEE cold neutron flux confirms the high cross section for this process on the ¹⁷⁷Lu^m isomer. The deviation from the 258±58 b previously published obtained for a Maxwellian neutron flux at a 323 K temperature, could be explained by the presence of a low energy resonance. Resonance parameters are deduced and discussed.