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(DMET)2MBr4 (M = Fe, Ga) are isostructural organic conductors whose crystal structure consists of an alternate stacking of quasi one-dimensional chain-based donor layers and anion square lattices. The resistivity, ESR, magnetic susceptibility, magnetization, and magnetoresistance of these salts were investigated in order to clarify the correlation between the electronic structure and the magnetism. The electronic structures of both salts are metallic down to TMI ∼40 K, below which a Mott insulating state is stabilized, accompanied by an SDW transition at TSDW ∼25 K. The FeBr4 salt with Fe3+ (S = 5/2) localized spins undergoes an antiferromagnetic transition at TN = 3.7 K. In the FeBr4 salt, the magnetization curves, which show field-direction-dependent anomalies in addition to a spin-flop transition, are demonstrated to have a participation of donor π-electron spins in the magnetization processes. The field dependence of the magnetoresistances below TN tracks faithfully that of the magnetization, where th...

A molecular conductor based on axially CN-substituted cobalt tetrabenzoporphyrin is reported. The crystal structure is isomorphous with a phthalocyanine-based conductor, however, estimation of effectiveness of π–π overlap and electrical transport measurement reveal that a slight change in molecular structure of macrocyclic π-conjugated ligands has significant influence on intermolecular interaction and electrical properties.

Organic charge transfer complexes form a large variety of electronic structures from insulating state to metallic state in low-dimensional frameworks, which are governed by the competition between ...

Crystal structure analyses, measurements of transport and magnetic properties, and low-temperature X-ray studies of new organic conductors: (ChTM-TTP)2AuBr2, (ChTM-TTP)2GaCl4, and (ChTM-TTP)ReO4, where ChTM-TTP is 2-[4,5-(1,2-cyclohexylenedithio)-1,3-dithiol-2-ylidene]-5-[4,5-bis (methylthio)-1,3-dithiol-2-ylidene]-1,3,4,6-tetrathiapentalene, have been carried out. In these compounds, the donors form quasi-one-dimensional columns with dimerization induced by the steric hindrance of the 1,2-cyclohexylene unit. The crystal structures and the energy band structures of both AuBr2- and GaCl4- salts are similar to those of the Bechgaard salts. The electrical resistivity and the thermoelectric power show metallic behavior above 100 K for the AuBr2- salt and above 150 K for the GaCl4- salt. The results of the ESR spin susceptibility, the static magnetic susceptibility, and the low-temperature X-ray studies indicate that the ground states of both salts are antiferromagnetic insulators. The Neel temperatures are ab...

A dielectric response by an intermolecular –N···H···O–proton transfer was observed around 120 K for (Chloranilic acid)(1,2-Diazine)2 [CA(1,2-DA)2]. This response, observed on the way of the migrati...

A manganese(III) complex salt, TPP[Mn I I I (Pc)(CN) 2 ]. DCM was crystallized in dichloromethane solution (Pc = phthalocyaninato, TPP + = tetraphenylphosphonium, and DCM = dichloromethane). In the crystal, Pc molecules form a pair of one-dimensional regular chains along the c axis. The magnetic susceptibility measurement revealed Mn ions in the low-spin state (S = 1) and a spin-orbit coupling effect due to the incomplete quenching of the angular orbital moment under the symmetrical ligand field.

As a new anode for the photoassisted oxidation of water, the TiN0.07O1.93 semiconductor electrode is proposed. Its photoanodic behavior in 0.1 M Na3PO4 was similar to those of n-type TiO2 electrodes, but the photocur-rent response was a little extended toward the long wavelength region. The electrode stability under the irradiation with ultraviolet light was good.