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Mellitate anions form hydrogen-bonding infinite networks in the salts with pyridinium cations. The network pattern depends on the number of deprotonation ($n)$from the mellitic acid; for n= 3, triangular hydrogen-bond units form a two-dimensional sheet, while for n= 2, dual hydrogen-bond units induce one-dimensional belts or two-dimensional grids. These self-organizing properties have been utilized for the crystal design of the TTF-type radical cation salts. Crystallization with TMTTF gave two kinds of crystals. One of the radical cation salt crystals consists of a channel network of the anions and one-dimensional columns of TMTTF in the channels. In the other TMTTF salt, the anions with $n = 1$form a two-dimensional sheet with methanol molecules. The TMTTF radicals are packed between the sheets with their molecular planes parallel to the anion planes. Key words.Hydrogen-bond – mellitate anion – crystal design – radical cation salt – infinite network.

In order to examine the possibility of (persistent) carrier doping to molecular crystals by light exposure, some different types of molecular crystals containing photoreactive species are synthesized and characterized. The [ Ru(bpy)3] 2+cation (bpy = 2,2'-bipyridyl) yielded two different new complexes with [ Ni(dmit)2] -radical species, both of which were structurally characterized and turned out to be band insulators. Methy viologen (MV) has been found to yield a new phase of the complex with [ Ni(dmit)2] -, MV[ Ni(dmit)2] 2. The temperature dependences of electrical resistivity (decreasing with lowering temperature down to 1.0 K) and magnetic susceptibility (Pauli paramagnetism from 300 K to 1.8 K with a hysteresis below ∼100 K) clearly indicate that this phase is metallic. The thermoelectric power exhibited ∼0 μVK-1from 300 K-4.2 K. This phase turned out to be metastable, and the crystals gradually turned into insulating ones. The effects of UV-VIS light exposure to the conducting and magnetic properties of Ag(DMe-DCNQI)2have been studied, and clear differences between the exposed and the pristine crystals were observed. The ESR signal at 3.7 K suggested that the exposed sample should include the Ag(0) species. Key words.Photoreaction – doping – conductivity.

We obtained three conducting crystals based on a [ FeIII(Pc)(CN)2] molecular unit. All crystals showed a large anisotropic negative magnetoresistance arising from the $\pi $-d interaction self-contained in the [ FeIII(Pc)(CN)2] unit. The anisotropy is attributable to the anisotropic g-tensor in the [ FeIII(Pc)(CN)2] unit. We also obtained a thin film containing [ FeII(Pc)(CN)2] . The film exhibits photocurrent response for the UV irradiation. These features suggest [ M(Pc)(CN)2] molecular unit is a well-designed one for a building block of molecular devices. Key words.Molecular electronics – phthalocyanine – $\pi $-d system – thin film.

A charge‐transfer complex of 2,5‐dimethyl‐N,N′‐dicyanoquinonediimine (DM) with silver (crystalline Ag(DM)2, defined as α) is irreversibly transformed by UV‐vis illumination. Depending on the illumination conditions, three new types of solids (defined as γ, δ, and ϵ) with different structural and physical properties are obtained and examined by a variety of analytical techniques, including solid‐state, high‐resolution, cross‐polarization magic angle spinning (CP‐MAS) 13C NMR, elemental analysis (EA), mass spectrometry (MS), X‐ray absorption fine structure (XAFS), and powder X‐ray diffraction (XRD). The CP‐MAS, EA, MS, and XAFS results indicate that compound γ is a glass state of Ag(DM)2. The transformation from crystalline (α) to amorphous (γ) solid Ag(DM)2is an irreversible exothermic glass transition (glass‐transition temperature 155.2 °C; ΔH= –126.8 kJ mol–1), which implies that the glass form is thermodynamically more stable than the crystalline form. Compound δ (Ag(DM)1.5) consists of silver nanoparticles (diameter (7 ± 2) nm ) dispersed in a glassy matrix of neutral DM molecules. The N–CN–Ag coordination bonds of the α form are not maintained in the δ form. Decomposition of α by intense illumination results in a white solid (ϵ), identified as being composed of silver nanoparticles (diameter (60 ± 10) nm). Physical and spectroscopic (XAFS) measurements, together with XRD analysis, indicate that the silver nanoparticles in both δ and ϵ are crystalline with lattice parameters similar to bulk silver; however, the magnetic susceptibilities differ from bulk silver.

Thermal analysis of Ag(DM)2, where DM = 2,5-dimethyl-N,N’- dicyanoquinonediimine, clarified that the salt had an insulating amorphous phase ( ≥ 155C). Characterization of this and related solid states of Ag(DM)2 indicated that a photo-induced process should be essential in controlling the number of carriers and thus conduction behavior of the salt by illumination. In fact, while heating could do nothing but make the salt insulating when the sample temperature exceeded 155C, ultraviolet-visible light illumination ( < 155C) could gradually change the properties to be semiconducting with retaining the crystal lattice (average structure).

Abstract: Thermal analysis of Ag(DM)2, where DM=2,5-dimethyl-N,N’-dicyanoquinonediimine, clarified that the salt had an insulating amorphous phase (≥155�C). Characterization of this and related solid states of Ag(DM)2 indicated that a photo-induced process should be essential in controlling the number of carriers and thus conduction behavior of the salt by illumination. In fact, while heating could do nothing but make the salt insulating when the sample temperature exceeded 155�C, ultraviolet-visible light illumination (<155�C) could gradually change the properties to be semiconducting with retaining the crystal lattice (average structure).

The binuclear Cu complex salts of 1, 4, 7‐trithiacyclononane (9S3) with an inorganic anion (BF4)‐and with an organic radical anion TCNQ‐(7, 7′, 8, 8′‐tetracyanoquinodimethanide) were synthesized and their molecular and crystal structures were examined in connection with the magnetic properties. The new complex cation [Cu(9S3)CN(9S3)Cu]+varies its charges and magnetic properties depending on the counter anions; [Cu(9S3)CN(9S3)Cu](BF4) (1) was obtained as diamagnetic colorless crystals, while [Cu(9S3)CN(9S3)Cu](TCNQ)2(2) was obtained as dark blue crystals with antiferromagnetic properties. Complex 1crystallized in the monoclinic space group C2/c with a= 26.863(2), b= 7.0878(5), c= 13.4864(8) Å, β= 116.318(2)°. Complex 2crystallized in the triclinic space group P1¯ with a= 12.521(1), b= 20.2698(8), c= 8.0205(4) Å, α = 100.688(4), β= 93.846(5), γ= 94.953(4)°. Both complexes are comprised of cyano‐bridged two Cu(9S3) ions with tetrahedral coordination. The X‐ray structural study revealed that 1has two crystallographically equivalent copper(I) atoms, while 2has two crystallographically independent CuI/IIsites. The two CuI/IIsites could not be distinguished from the X‐ray structural study. For 2the IR spectra show that both crystallographically independent TCNQ species were monoanions and are strongly dimerized due to π‐stacking, which well explains their diamagnetic contribution to the magnetic susceptibility and the highly insulating property of this salt. The temperature‐dependent magnetic susceptibility of 2showed a deviation from the Curie‐Weiss behaviour around 60 K, which indicates a strong antiferromagnetic intermolecular interaction between the copper complexes and that such intermolecular interaction should partly occur via the TCNQ radical anion dimer.

Air-oxidation of the acetone–acetic acid solution of (C₇H₁₃NH)₂[Pd(dmit)₂] yielded black shiny platelets of (C₇H₁₃NH)[Pd(dmit)₂]₂. The crystal structure was characterized by a criss-cross columnar structure, which has been often observed in M(dmit)₂-based (M = Ni, Pd) superconductors. Although the quinuclidinium cation (C₇H₁₃NH)+ is found to be orientationally disordered on a 2-fold axis, the crystal exhibited metallic conductivity down to ~ 40 K. Under ambient pressure the room temperature conductivity is around 22 S cm−1 and the resistivity gradually decreased with decreasing temperature down to 200 K, where it suddenly started to decrease more rapidly and kept decreasing down to ~ 40 K, where it started to increase steeply. At ca. 200 K the structural transition occurred, yet the crystal and molecular structures remained practically unaffected including the cation site disorder and the strong dimerization of the Pd(dmit)₂ molecules. The electrical behaviour under high pressure was rather unusual but could be compared with structurally related Pd(dmit)₂-based superconductors.

Single crystals of H2(Pc)I behave as a "molecular metal" with σRT ≈ 700 Ω-1cm-1 (σ‖/σ⊥ ≈ 500) and σmax ≈ 4000 Ω-1cm-1. The static magnetic susceptibility is Paulilike, and a Drude analysis of the optical reflectivity yields a tight-binding bandwidth of 0.77(7) eV.

Electrically conductive polymers have been prepared from the cofacially joined metallophthalocyanine polymer [Si(Pc)o]na Optical and electrical properties are investigated as a function of the type and degree of the incremental doping added to form the {[Si(Pc)o] Xy }n systems. The dopants are: X = BF4 PF6, SbF6 and I. In spite of the variation in structural and electronic characteristics of the doping agents, there is a considerable similarity in the behavior of the electronic transport.

The single crystals of (TSeC1-TTF)XHgBr2have been prepared, which show the lowest resistivity among the TSeC1-TTF complex. In the present paper their electrical and magnetic properties are reported.

This paper will summarize highlights of the safety approach and discuss the ITER EDA safety activities. The ITER safety approach is driven by three major objectives: (1) Enhancement or improvement of fusion's intrinsic safety characteristics to the maximum extent feasible, which includes a minimization of the dependence on dedicated “safety systems”; (2) Selection of conservative design parameters and development of a robust design to accommodate uncertainties in plasma physics as well as the lack of operational experience and data; and (3) Integration of engineered mitigation systems to enhance the safety assurance against potentially hazardous inventories in the device by deploying well-established “nuclear safety” approaches and methodologies tailored as appropriate for ITER.

In order to clarify a proton-transfer mechanism, the dependence of proton-transfer rate on the hydrogen-bond length was investigated. The proton-transfer rate in four thermochromic N-salicylideneanilines (SAs) in a crystalline phase was estimated by a femtosecond time-resolved fluorescence spectroscopy. The transfer rate is given by k0 exp(−αδr) (α = 9.0 Å^-1) as a function of the tunneling distance δr, where k0 is the O−H stretching frequency. The proton-transfer rate is insensitive to a sample temperature and shows a deuteration effect. From these results, it is concluded that the photoinduced proton transfer in the excited state of SAs takes place by the quantum mechanical tunneling.

The substitution effect on the dynamics of the proton transfer in thermochromic salicylideneanilines in the crystalline phase was investigated using femtosecond time-resolved fluorescence spectroscopy. From the deuteration effect and low-temperature measurement, it is concluded that the proton tunnels the potential barrier quantum-mechanically in the excited state. The rate of proton transfer was found to decrease with the energy separation between the excited enol and keto forms due to the different potential-barrier heights. The change in the potential-barrier height is qualitatively explained by the electron-donating or -accepting property of the substituent around the hydrogen bond. The thermalization of the vibrational states of the excited enol form was also observed.

Magnetic cation of Co²⁺ was incorporated in a monovalent [Ni(dmit)2]^- (2-thioxo-1,3-dithiole-4,5-dithiolate) salt by using the supramolecular framework of 15-crown-5. The π-spins of [Ni(dmit)2]^- formed a one-dimensional Heisenberg antiferromagnetic linear chain, while the d-spin of Co²⁺ behaved as a free S = 3/2 spin within the crystal.

We studied impurity effects on the magnetic properties of p-EPYNN^+ . [Ni(dmit)"2]-(p-EPYNN^+=p-N)-ethylpyridinium nitronylnitroxide and [Ni(dmit)"2] (dmit=1,3-dithiol-2-thione-4,5-dithiolate), whose crystal involved a molecular spin ladder of [Ni(dmit)"2]^- sandwiched by side-by-side and head-to-tail stacking chains of p-EPYNN^+, by means of partial replacement of paramagnetic [Ni(dmit)"2]^- with non-magnetic [Au(dmit)"2]^-. In the solid solutions, p EPYNN^+. [Nidmit)"2]-"1"-"x[Au(dmit)"2]-"x, an increase in x results in an increase of paramagnetic lattice defects on the spin ladder of [Ni(dmit)"2]^-, which become pathes of an antiferromagnetic interaction between the ferromagnetic chains of p-EPYNN^+.

Paramagnetic Fe(III) has been introduced into molecular conductors based on axially substituted metal phthalocyanine for the purpose of constructing a system which has magnetic spins on the conduction paths. Some crystals have been obtained from the electrochemical oxidation of [Fe(III)(Pc)(CN)2]−. The crystal structures are the same as the cases where the metal ion is Co(III), but their physical properties are quite different.

Supramolecular assemblies of ammonium ions (NH4+) with crown ethers form a variety of NH4+(crown ether) supramolecular cation (SC+) structures within the range of [Ni(dmit)2] salts. A new pyramidal NH4+(12-crown-4) structure is found in the NH4+(12-crown-4) [Ni(dmit)2]3(CH3CN)2 salt. The SC+ structures in the NH4+(crown ether)[Ni(dmit)2] series vary from pyramidal-, sandwich-, to disk-shaped-structures with the crown ethers 12-crown-4, 15-crown-5, and 18-crown-6, respectively.

Charge transfer (CT) complexes of tetrathiafulvalene bisannulated 24-crown-8 (1) with tetrafluoro (F4)-, 2,5-dibromo (Br2), 2,5-dichloro (Cl2)-tetracyanoquinodimethane (TCNQ), and 2,3-dicyano-5,6-dichloro-p-benzoquinone (DDQ) were prepared. The electronic ground state of the acceptor varies from the completely ionic to partial charge transfer state. Within the CT complexes the donor 1 was completely oxidized to the divalent cationic state 12+. The molecular conformation of 12+ in Cl2-TCNQ complex was an intra-dimer form folded over the flexible part of macrocyclic 24-crown-8.

Supramolecular assemblies of ammonium ions (NH4+) with crown ethers form a variety of NH4+(crown ether) supramolecular cation (SC+) structures within the range of [Ni(dmit)2] salts. A new pyramidal NH4+(12-crown-4) structure is found in the NH4+(12-crown-4) [Ni(dmit)2]3(CH3CN)2salt. The SC+structures in the NH4+(crown ether)[Ni(dmit)2] series vary from pyramidal-, sandwich-, to disk-shaped-structures with the crown ethers 12-crown-4, 15-crown-5, and 18-crown-6, respectively.

Charge transfer (CT) complexes of tetrathiafulvalene bisannulated 24-crown-8 (1) with tetrafluoro (F4)-, 2,5-dibromo (Br2), 2,5-dichloro (Cl2)-tetracyanoquinodimethane (TCNQ), and 2,3-dicyano-5,6-dichloro-p-benzoquinone (DDQ) were prepared. The electronic ground state of the acceptor varies from the completely ionic to partial charge transfer state. Within the CT complexes the donor 1 was completely oxidized to the divalent cationic state 12+. The molecular conformation of 12+in Cl2-TCNQ complex was an intra-dimer form folded over the flexible part of macrocyclic 24-crown-8.

Paramagnetic Fe(III) has been introduced into molecular conductors based on axially substituted metal phthalocyanine for the purpose of constructing a system which has magnetic spins on the conduction paths. Some crystals have been obtained from the electrochemical oxidation of [Fe(III)(Pc)(CN)2]−. The crystal structures are the same as the cases where the metal ion is Co(III), but their physical properties are quite different.

The octahydroanthracene (I) is brominated and then substituted with the sodium salt (III) of malononitrile to give the tetrakis(dicyanomethyl) derivative (IV).

The cyclic voltammogram of the title compound (V) exhibits 4 redox waves.

The previously prepared compound (I) crystallizes in P21/a with Z=2.