久保 和也

This minireview discusses recent advances in transition metal complexes for electrochromic (EC) and electrofluorochromic (EFC) devices. EC and EFC materials can switch their color and photoluminescence, respectively, through electrochemical redox reactions. Transition metal complexes offer promising opportunities due to their molecular design versatility for various optoelectrical properties. The review provides an overview of electrochromism and electrofluorochromism, including performance characterization methods and device fabrication techniques. It highlights EC transition metal complexes that can form thin films suitable for device applications and EFC transition metal complexes that can efficiently tune photoluminescence through electrochemical quenching mechanisms. The review also summarizes advanced functions of EC/EFC transition metal complexes, including large optical contrast, fast response, dual-switching of color and emission, and easy device fabrication, which could lead to low-cost displays. Overall, this review article presents the latest research on transition metal complexes for EC and EFC devices and their potential for practical applications.

We report the synthesis of P-BT and TP-BT and their OTFT properties based on electronic dimensionality and access resistance (R_acc). TP-BT can suppress R_acc due to its 3D electronic structure.

The effects of substituents on the arrangement of metal–dithiolene complexes based on π-conjugated systems, which are extensively used to synthesize various functional materials, have not been studied adequately. New donor-type nickel–dithiolene complexes fused with bulky cycloalkane substituents [Ni(Cn-dddt)2] (C5-dddt = 4a,5,6,6a-pentahydro-1,4-benzodithiin-2,3-dithiolate; C6-dddt = 4a,5,6,7,8,8a-hexahydro-1,4-benzodithiin-2,3-dithiolate; C7-dddt = 4a,5,6,7,8,9,9a-heptahydro-1,4-benzodithiin-2,3-dithiolate; and C8-dddt = 4a,5,6,7,8,9,10,10a-octahydro-1,4-benzodithiin-2,3-dithiolate) were synthesized in this study. All the complexes were crystallized in cis-[Ni(cis-Cn-dddt)2] conformations with cis-oriented (R,S) conformations around the cycloalkylene groups in the neutral state. Unique molecular arrangements with a three-dimensional network, a one-dimensional column, and a helical molecular arrangement were formed in the crystals owing to the flexible cycloalkane moieties. New 2:1 cation radical crystals of [Ni(C5-dddt)2]2(X) (X = ClO4− or PF6−), obtained by electrochemical crystallization, exhibited semiconducting behaviors (ρrt = 0.8 Ω cm, Ea = 0.09 eV for the ClO4− crystal; 4.0 Ω cm, 0.13 eV for the PF6− crystal) under ambient pressure due to spin-singlet states between the dimers of the donor, which were in accordance with the conducting behaviors under hydrostatic pressure (ρrt = 0.2 Ω cm, Ea = 0.07 eV for the ClO4− crystal; 1.0 Ω cm, 0.12 eV for the PF6− crystal at 2.0 GPa).

We report the structural and physical properties of a new organic Mott insulator (BEDT-BDT)AsF6 (BEDT-BDT: benzo[1,2-g:4,5-g′]bis(thieno[2,3-b][1,4dithiin). This AsF6 salt has the same structure as the PF6 salt. Although the anions are disordered, the donor molecules form a θ-type arrangement. The temperature dependence of the resistivity exhibits semiconducting behavior. The static magnetic susceptibility follows Curie–Weiss law over a wide temperature range; however, below 25 K, the magnetic susceptibility is in agreement with a one-dimensional chain model with the exchange coupling J = 7.4 K. No structural phase transition was observed down to 93 K. At 270 K, the Fermi surface calculated by the tight-binding approximation is a two-dimensional cylinder; however, it is significantly distorted at 93 K. This is because the dihedral angles between the BEDT-BDT molecules become larger due to lattice shrinkage at low temperatures, which results in a smaller transfer integral (t1) along the stack direction. This slight change in the dihedral angle gives rise to a significant change in the electronic structure of the AsF6 salt. Radical-cation salts using BEDT-BDT, in which the highest occupied molecular orbital does not have a dominant sign throughout the molecule, are sensitive to slight differences in the overlap between the molecules, and their electronic structures are more variable than those of conventional θ-type conductors.

Molecular motion within crystals can significantly affect their dielectric properties and functionalities. Crystals of (m-XAni(+)) (DB[18]crown-6) [Ni(dmit)2](-) (m-XAni(+) = m-halogenated anilinium (X = F, 1), (X = Cl, 2), (X = Br, 3), and (X = I, 4); DB[18]crown-6 = dibenzo[18]crown-6; dmit(2-) = 2-thioxio-1,3-dithiol-4,5-dithiolate) were synthesized, and the substituent effects of crystals 2-4 were discussed in terms of crystal structure, dielectric response, and molecular motion compared with crystal 1, which exhibited a ferroelectric transition due to the flip-flop motion of the m-FAni(+) cation. Although crystals 2-4 did not show rotational disorder of the aryl groups due to the larger size of the halogen atoms, in- and out-of-plane pendulum motions were observed. Temperature-dependent crystallographic analysis revealed that crystal 2 underwent a symmetry reduction from space group P2(1)/m at 293 K to P2(1) at 93 K with the disappearance of the mirror plane on m-ClAni(+) associated with the stopping of the out-of-plane pendulum motion. In the case of crystals 3 and 4, an in-plane pendulum motion at small swing angles was suggested, which was further supported by potential energy calculations. Owing to the semiconducting nature of the crystals, these pendulum motions could not be detected by dielectric measurements.

We report a crystal structure analysis of an unsymmetrical organic semiconductor 2-bromo-7-butyl[1]benzothieno[3,2-b][1]benzothiophene (Br-BTBT-C ) and its transistor characteristics. Unlike the parent compound 2-butyl-[1]benzothieno[3,2-b][1]benzothiophene (BTBT-C ) forming a bilayer-type structure composed of head-to-head herringbone packings, Br-BTBT-C forms a dense head-to-tail herringbone packing arranged so as to avoid the steric hindrance between bromine atoms. The intermolecular transfer integrals in Br-BTBT-C suggest its advantage for carrier transport; however, the transistor characteristics of Br-BTBT-C and BTBT-C were found to be almost the same. This is because BTBT-C has a higher crystallinity than Br-BTBT-C in vacuum deposited thin films. 4 4 4 4 4 4 4 4

<p>The solid solutions composed of different ratios of two Werner complexes showed controlled acetone gate-sorption properties.</p>

<p>We have succeeded in developing a two-dimensional radical–cationic Mott insulator that does not contain a 1,3-dithiol-2-ylidene moiety.</p>

<p>POM based non-centrosymmetric inorganic–organic hybrids are designed by gradually introducing asymmetry into the building units.</p>

We attempted the synthesis and crystallographic characterization of light-metal coordination polymers (CPs) using a 4-(methylsulfonyl)benzoate (msbza(-)) ligand with a charge-polarized neutral methylsulfonyl coordination moiety, in order to diversify the limited structures of light-metal CPs, as compared with heavy-metal CPs. As expected from the results of DFT calculations, all of the obtained CPs {three-dimensional (3D) [Mg2Na2(msbza)(6)(H2O)(3)](n) (1), two-dimensional (2D) [KH(msbza)(2)](n) (2) and 2D [Na(msbza)](n) (3)} exhibited coordination of the methylsulfonyl moiety to light-metal cations, in addition to coordination of the carboxylate. These structural features suggest that the use of a neutral methylsulfonyl coordination site is a powerful tool for the structural diversification of light-metal CPs. In addition, the 3D CP 1, with the rare and unique tetranuclear Mg2Na2 secondary building unit, showed an unprecedented single-crystal-to-single-crystal transformation via the low-crystalline state.

The Mott transition-a metal-insulator transition caused by repulsive Coulomb interactions between electrons-is a central issue in condensed matter physics because it is the mother earth of various attractive phenomena. Outstanding examples are high-Tc (critical temperature) cuprates and manganites exhibiting colossal magnetoresistance. Furthermore, spin liquid states, which are quantum-fluctuation-driven disordered ground states in antiferromagnets, have recently been found in magnetic systems very near the Mott transition. To date, intensive studies on the Mott transition have been conducted and appear to have established a nearly complete framework for understanding the Mott transition. We found an unknown type of Mott transition in an organic spin liquid material with a slightly disordered lattice. Around the Mott transition region of this material under pressure, nuclear magnetic resonance experiments capture the emergence of slow electronic fluctuations of the order of kilohertz or lower, which is not expected in the conventional Mott transition that appears as a clear first-order transition at low temperatures. We suggest that they are due to the unconventional metal- insulator fluctuations emerging around the disordered Mott transition in analogy to the slowly fluctuating spin phase, or Griffiths phase, realized in Ising spin systems with disordered lattices.

Mechanoresponsive luminescent (MRL) compounds change their emission color upon mechanical treatment. Hundreds of MRL compounds have been studied, but their mechanically triggered response at elevated temperature has remained virtually unexplored. Here, we demonstrate that the temperature can have a significant influence on the mechanically induced response of MRL compounds. The photoluminescence of a new cyano-substituted oligo(p-phenylenevinylene) derivative was shown to exhibit a significant red-shift when ground at ambient temperature, whereas the same treatment at 100 degrees C leads to a hypsochromic shift. The behavior at ambient is caused by a mechanically induced phase transition from a crystalline to an amorphous solid in which the dye molecules form excimers, whereas at elevated temperature the hypsochromic shift is ascribed to a crystalline-crystalline phase transition. Such temperature-dependent MRL behavior was not previously observed, but it appears to be a general effect that is useful for sophisticated mechano-sensing materials and devices.

Crystallization of neutral 3,5-pyridinedicarboxylic acid N-oxide (H-2-3,5-pydcao) molecules in the presence/absence of solvent molecules affords neutral hydrogen bond-supported one-dimensional, two-dimensional, and three-dimensional molecular networks of H-2-3,5-pydcao center dot DMF (1 center dot DMF), H-2-3,5-pydcao center dot H2O (1 center dot H2O), and H-2-3,5-pydcao (1), respectively, that have strong intermolecular hydrogen bonds of N delta+-O delta-center dot center dot center dot HOOC. These molecular networks were found to show reversible structural changes among 1, 1 center dot H2O, and 1 center dot DMF driven by solvent release/uptake.

A two-dimensional (2D) layered Mg-II coordination polymer (CP) with a high tolerance for H2O was designed, synthesised, and crystallographically characterised. The synthesis was achieved by the introduction of a flexible 2D layered structure composed of MgII ions and isonicotinate N-oxide ligands. Owing to its high H2O tolerance, the obtained 2D layered structure has the flexibility to repeatedly adsorb a large amount of H2O associated with interlayer expansion and enable the removal of H2O from a H2O/2-propanol mixed vapour. These results indicate that the CP could be an excellent dehydrating agent.

It has been known that sample dimension and lattice defects affect critical behavior of superconductivity. Particular type of porous samples called fractal bodies have well-defined non-integer dimensions dependent exclusively on the geometrical feature of structures. Differences in sample dimension and lattice defects are quantitatively described by such fractal dimensions (Ds). Powder samples of high-T&lt;sub&gt;C&lt;/sub&gt; cuprates with 2.5 &lt; D &lt; 3 were prepared, and their superconducting properties were compared as regards critical temperature T&lt;sub&gt;C&lt;/sub&gt;, critical current J&lt;sub&gt;C&lt;/sub&gt;, and critical magnetic field H&lt;sub&gt;C&lt;/sub&gt;. While the variation in H&lt;sub&gt;C&lt;/sub&gt; for different Ds was within experimental error (for the lower H&lt;sub&gt;C&lt;/sub&gt;) or too high to be measured (for the upper H&lt;sub&gt;C&lt;/sub&gt;), T&lt;sub&gt;C&lt;/sub&gt; and J&lt;sub&gt;C&lt;/sub&gt; correlated with D: they both exhibited complex patterns of D-dependence immediately below D = 3 and maximum enhancement of ∽0.7% in T&lt;sub&gt;C&lt;/sub&gt; and ∽7% in J&lt;sub&gt;C&lt;/sub&gt; were observed. The observed behavior is semi-quantitatively explained by considering fractal structures of the samples. In addition, the D-dependences of T&lt;sub&gt;C&lt;/sub&gt; and J&lt;sub&gt;C&lt;/sub&gt; are explained with the same quantitative discussion as those of Néel temperatures of fractal CoO powder samples. This suggests underlying universal physics for cooperative phenomena in fractal dimensions.

Coordination polymers based on oxalate-bridged {[(MnCrIII)-Cr-II- (oxalate)(3)](-)}(infinity) complexes of (DAT-2H(2+))(DCH[18]crown-6)(2)[Mn-II(CH3OH)Cr-III(oxalate)(3)](-)(2)(CH3OH)(3) and (DABCO-H+)(2)(DABCO-2H(2+))[Mn-II(CH3OH)(Cl-)Cr-III(oxalate)(3)](2-)(2-) (CH3OH), where DAT, DABCO, and DCH[18]crown-6 denote 2,5-diaminotoluene, 1,4-diazabicyclo[2.2.2]octane, and cis-syncis-dicyclohexano[18]crown-6, respectively, were synthesized. The crystal structure of the former complex was composed of [Mn-II(Lambda)(CH3OH)Cr-III(Lambda)(oxalate)(3)](-) units, whereas that of the latter crystal was composed of [Mn-II(Lambda)(CH3OH)(Cl-)-Cr-III (Delta)(oxalate)(3)](2-) units. The large flexible supramolecular cation in the former provided the two-dimensional structure of [Mn-II(Lambda)(CH3OH)Cr-III(Lambda)(oxalate)(3)](-), although the two-dimensional honeycomb structure of the {[Mn-II(Delta)Cr-III(Lambda)-(oxalate)(3)](-)}infinity and {[Mn-II(Lambda)Cr-III(Delta)(oxalate)(3)](-)}(infinity) networks are often observed for the oxalate complexes. The round-shaped DABCO molecule in the latter induced a one-dimensional chain structure of [Mn-II(Lambda)(CH3OH)Cr-III(Delta)(oxalate)(3)](-). The former crystal showed a magnetic field dependence of magnetization typical for a spin-canting system.

To investigate the network structure of inorganic organic hybrid crystals, we synthesized a series of assemblies based on polyoxometallates (POMs) [SMo12O402-] and different supramolecular cations consisting of anilinium and crown ether derivatives. The compounds [(m-XAni(+))(B-[18]crown-6)](2)[SMo12O402-] (Ani(+) = anilinium; B [18] crown-6 = benzo[18]crown-6; X = F (1), Cl (2), Br (3), or I (4)), [ (4-MeAn(+)) (B [18] crown-6)](2)[SMo12O4020]center dot CH3CN (5), [(4-MeAni(+)) (DB [18] crown-6)](2)[SMo12O402-]center dot 2CH(3)CN (6), [(3-F-4-MeAni(+)) (DB [18] crown-6)](2)[SMo12O402-]center dot 2CH(3)CN (7), and [ (3-F-4-MeAni(+))(2)(DB [30]crown-10)] [SMo12O402-]center dot 2CH(3)CN (8) (4-MeAni(+) = 4-methylanilinium; DB [18] crown-6 = dibenzo[18]crown-6; 3-F-4-MeAni = 3-fluoro-4-methylanilinium; DB[30] crown-10 = dibenzo[30]crown-10) were synthesized. Their crystal architectures were characterized according to the size and charge of the supramolecular cations. In 1-4, two adjacent supramolecular cations ([(m-XAni(+))(B[18]crown-6)]) were connected through pi center dot center dot center dot pi interactions forming sandwich-type dimers with the cations that were stacked in an antiparallel manner. In 8, DB[30] crown-10 included two cations constructing a larger divalent supramolecular cation [(3-F-4-MeAni(+))(2)(DB[30]crown-10)]. In 1-4 and 8, the ratio between [SMo12O402-] and the supramolecular cations was 1:1, and the latter formed rectangular-assembled structures. In 5, the pi center dot center dot center dot pi stacking interaction was present in the adjacent B[18]crown-6. Monovalent supramolecular cations were present in 5-7 with a ratio of 1:2 between [SMo(12)O4(02)(-)] and the supramolecular cations. The supramolecular cations formed hexagonal-assembled structures.

Supramolecular crystals having one-dimensional (1d) columnar structures were constructed by using supramolecules based on tst-DCH[18]crown-6 (tst-DCH = trans-syn-trans-dicyclohexano). In the crystal of (Ani(+))(tst-DCH[18]crown-6)[Ni(dmit)(2)](-) (1) and (m-FAni(+))(tst-DCH[18]crown-6)[Ni(dmit)(2)](-) (2) (Ani(+) = anilinium(+), m-FAni(+) = m-fluoroanilinium(+), dmit(2-) = 2-thioxo-1,3-dithiole-4,5-dithiolate), the tst-DCH[18]crown-6 formed supramolecular cations with Ani(+) and m-FAni(+), respectively, through N-H center dot center dot center dot O hydrogen bonds. The planar conformation of tst-DCH[18]crown-6 molecules in the crystals provided bidirectional hydrogen bonding from the upper and lower side of the molecule that were the driving forces for the construction of the 1d supramolecular architecture. The results provided a method to control arrangements of crown ether-based supramolecules in 1d columns that could be used for channels and/or molecular nanomachines such as molecular rotators.

Porous coordination polymers (PCPs) that show a gate-type adsorption originating from structural flexibility represent a new concept for developing gas separation materials. Here, the gas adsorption and separation properties of a flexible one-dimensional (1D) copper(II) PCP, [Cu(BF4)(2)(1,3-bis(4-pyridyl) propane)(2)](n) were evaluated. The single-gas adsorption isotherms revealed different gate-opening pressures for CO2 and C1 similar to C4 linear alkanes, suggesting great possibility for the separation of mixtures of these gases. The gas separation properties were characterized by performing breakthrough experiments at ambient temperature using CH4/CO2 and CH4/C2H6 mixtures. The results demonstrated the practical utility of 1D PCPs in gas separation applications. Single-crystal X-ray diffraction analysis demonstrated high structural adjustability for the incorporation of a variety of guest molecules. (C) 2015 Elsevier Inc. All rights reserved.

The development of highly efficient CO2 separation materials is very important for environmental preservation and energy conservation. Crystalline porous coordination polymers (PCPs)/metal-organic frameworks are one of a number of promising types of porous materials for CO2 separation because of their controllable pore size, shape and surface function. Simultaneously, the unique structural flexibility of PCPs affords both high CO2 selectivity and inexpensive regeneration. However, this family of materials suffers from the coexistence of water that destroys the framework of PCPs and its adsorption in the pores is greater than that of CO2, which results in a deterioration in CO2-separation performance. Herein, a flexible and hydrophobic CuII PCP that is stable towards water has been designed and synthesised. This PCP has extremely high adsorption selectivity for CO2 over CH4, derived from its structural flexibility. Furthermore, the obtained water-tolerant flexible PCP, under CO2/CH4 mixed-gas conditions, exhibits highly selective CO2 adsorption over CH4, even in the presence of water.

The design of inexpensive and less toxic porous coordination polymers (PCPs) that show selective adsorption or high adsorption capacity is a critical issue in research on applicable porous materials. Although use of Group II magnesium(II) and calcium(II) ions as building blocks could provide cheaper materials and lead to enhanced biocompatibility, examples of magnesium(II) and calcium(II) PCPs are extremely limited compared with commonly used transition metal ones, because neutral bridging ligands have not been available for magnesium(II) and calcium(II) ions. Here we report a rationally designed neutral and charge-polarized bridging ligand as a new partner for magnesium(II) and calcium(II) ions. The three-dimensional magnesium(II) and calcium(II) PCPs synthesized using such a neutral ligand are stable and show selective adsorption and separation of carbon dioxide over methane at ambient temperature. This synthetic approach allows the structural diversification of Group II magnesium(II) and calcium(II) PCPs.

The one-dimensional Zn(II) coordination polymer, {[Zn-2(chdc)(2)(mepy)(4)]center dot 6H(2)O}(n) (1 superset of 6H(2)O, chdc: trans-1,4-cyclohexanedicarboxylate and mepy: 4-methylpyridine), stabilized unique water aggregate, finite winding (H2O)(12) chains.

Supramolecular cation salt of adamantane rotator with a dithiolene complex, (fluoroadamantylammonium(+))([18]-crown-6)[Ni(dmit)(2)](-) (1) was synthesized. The fluorine atom of the adamantane unit showed a large thermal factor elongated latitudinally, suggesting molecular rotation in the solid state. Crystal 1 exhibited a large dielectric response by applying an AC field along the a axis.

4-Methylanilinium derivatives were used to introduce spaces for molecular rotation in crystals. The [Ni(dmit)(2)](-) (dmit(2-) = 2-thioxo-1,3-dithiole-4,5-dithiolate) salts with supramolecular cations of dibenzo[18]crown-6 (DB[18]crown-6) and 4-methylanilinium derivatives, (4-methylanilinium(+))(DB[18]crown-6)[Ni(dmit)(2)](-) (1), (2-fluoro-4-methylanilinium(+))(DB[18]crown-6)[Ni(dmit)(2)](-) (2), and (3-fluoro-4-methylanilinium(+))(DB[18]crown-6)[Ni(dmit)(2)](-) (3) were synthesized. The potential energy curves for the molecular rotations of the cations in the crystals had double minimum shapes with maxima of 100, 210, and 230 kJ mol(-1) for crystals 1, 2, and 3, respectively. Introduction of a methyl substituent at the p-position was effective in reducing the potential energy maxima. For crystals 2 and 3, large dielectric responses originating from the flip-flop motions of the cationic molecules were observed upon applying an AC voltage. The temperature-dependent magnetic susceptibilities of complexes 1, 2, and 3 followed the Curie-Weiss law, showing weak antiferromagnetic interactions.

It is well-known that cooperative properties such as magnetic ordering can depend on the samples' dimensions (Ds) in a qualitative way. However, there have been no samples with well-defined non-integer Ds. The dimension of a given sample has been always discussed on the anisotropy of the electronic/crystal/magnetic structures, which has no definition suitable for quantitative discussion on dimensions vs. properties. On the other hand a particular type of porous samples, i.e. fractal bodies, can have well-defined non-integer Ds dependent exclusively on the geometrical feature of structures, and physical properties of such materials remains unexplored. This paper reports on magnetic ordering in samples covering 2.5 &lt;= D &lt;= 3, in addition to a way of precise control of the fractal dimensions of given samples simply by wax (alkylketene dimer). The results show that the magnetic ordering temperatures, i.e. Neel temperatures (T(N)s), of CoO depend on D, and rapidly enhance immediately below D = 3. This means that one can control or enhance the critical temperature simply by tuning D with keeping the remaining magnetic properties unchanged.

Ferroelectricity is essential to many forms of current technology, ranging from sensors and actuators to optical or memory devices. In this circumstance, organic ferroelectrics are of particular importance because of their potential application in tomorrow's organic devices, and several pure organic ferroelectrics have been recently developed. However, some problems, such as current leakage and/or low working frequencies, make their application prospects especially for ferroelectric memory (FeRAM) not clear. Here, we describe the molecule-displacive ferroelectricity of supramolecular adducts of tartaric acid and 1,4-diazabicyclo[2.2.2]octane N,N'-dioxide. The adducts show large spontaneous polarization, high rectangularity of the ferroelectric hysteresis loops even at high operation frequency (10 kHz), and high performance in polarization switching up to 1 x 10(6) times without showing fatigue. It opens great perspectives in terms of applications, especially in organic FeRAM.

The use of divalent Cu-II ions and an anion-mixing method led to the rational construction of a porous coordination polymer bridged by weak Lewis base inorganic CF3SO3- monoanions.

Porous coordination polymer (PCP) polymorphs with the formula [Cu(CF3SO3)(2)(bpp)(2)](n) [1 and 2, where bpp = 1,3-bis(4-pyridyl)propane] have been synthesized and crystallographically characterized, and their distinguishable porous properties have been investigated. 1 was obtained by the removal of guest acetone molecules from one-dimensional PCP {[Cu(CF3SO3)(bpp)(2)]center dot CF3SO3 center dot 2acetone}(n) (1 superset of 2acetone), while 2 was derived from two-dimensional PCP {[Cu(CF3SO3)(2)(bpp)(2)]center dot H2O} (2 superset of H2O) by the loss of guest H2O molecules. The desolvated PCPs 1 and 2 with the same formula [Cu(CF3SO3)(2)(bpp)(2)] showed distinguishable structures, suggesting PCP polymorphs. In addition, their adsorption behaviors were completely different: 1 showed adsorption with the structural transformation from closed to open forms, while 2 appeared to expand its framework for only as long as was required for the passage of guest molecules. To the best of our knowledge, PCP polymorphs showing either of two different types of flexible pores are very rare.

Two new isostructural molecular metals-(BDH-TTP)6[M-III(C5O5)(3)]center dot CH2Cl2 (BDH-TTP = 2,5-bis(1,3-dithiolan-2-ylidene)-1,3,4,6-tetrathiapentalene, where M = Fe (1) and Ga (2))-have been prepared and fully characterized. Compound 1 is a molecular conductor showing paramagnetic behavior, which is due to the presence of isolated [Fe(C5O5)(3)](3-) complexes with high-spin S = 5/2 Fe(III) metal ions. The conductivity originates from the BDH-TTP organic donors arranged in a kappa-type molecular packing. At 4 kbar, compound 1 behaves as a metal down to similar to 100 K, showing high conductivity (similar to 10 S cm(-1)) at room temperature. When applying a pressure higher than 7 kbar, the metal-insulator (M-I) transition is suppressed and the compound retains the metallic state down to low temperatures (2 K). For 1, ESR signals have been interpreted as being caused by the fine structure splitting of the high-spin (S = 5/2) state of Fe(III) in the distorted octahedral crystal field from the ligands. At 4 kbar, the isostructural compound 2 behaves as a metal down to similar to 100 K, although it is noteworthy that the M-I transition is not suppressed, even at pressures of 15 kbar. For 2, only the signal assigned to delocalized pi-electrons has been observed in the ESR measurements.

Supramolecular cations formed by monoprotonated pyridazinium cations and cis-anti-cis-dicyclohexano-[18]-crown-6 (DCH[18]-crown-6) or dibenzo[18]-crown-6 (DB[18]-crown-6) were introduced into [Ni(dmit)(2)](-) salts (where dmit(2-) = 2-thione-1,3-dithiole-4,5-dithiolate). X-ray crystal structure analysis of (pyridazinium(+))(DCH[18]-crown-6)[Ni(dmit)(2)](-) (1) revealed a chair-type conformation of the DCH[18]-crown-6 moiety. A V-shaped conformation of the DB[18]-crown-6 moiety was observed in (pyridazinium(+))(DB[18]-crown-6)(2)[Ni(dmit)(2)](-)(H2O)(2) (2). Nitrogen atoms in the pyridazinium cations interacted with the oxygen atoms of the DCH[18]-crown-6 and DB[18]-crown-6 through N-H+similar to O hydrogen bonds, forming 1 : 1 and 1 : 2 supramolecular structures, respectively. Sufficient space for molecular motions of the pyridazinium cations, namely flip-flop and in-plane rotations, exists in salt 1. Disorder in nitrogen atoms was observed by X-ray analysis, indicating dynamic motion of the pyridazinium cation, namely flip-flop motion and in-plane motion. A potential energy calculation further supported the possibility of dynamic motion of cations in the crystal. By contrast, the flip-flop motion of the pyridazinium group in salt 2 is restricted by the two nearest-neighbouring DB[18]-crown-6 molecules. Weak antiferromagnetic intermolecular interactions between the [Ni(dmit)(2)](-) anions in the two-dimensional layers of salt 1 were observed, resulting in alternating antiferromagnetic Heisenberg chain-type magnetic susceptibility. Quasi-one-dimensional intermolecular interactions between the [Ni(dmit)(2)](-) anions were observed in salt 2, whose magnetic behaviour followed the Bonner-Fisher model.

Single crystal of supramolecuar cation salt (adamantylammonium +)2(benzo[18]crown-6)2[Pd(dmit) 2]2-(- acetone)2 were synthesized by an electrochemical crystallization. In the crystal, two supramolecular cations and two acetones and one [Pd(dmit)2]2- dianion were crystallographically asymmetric. Molecular rotation of adamantyl groups was suggested from anisotropic thermal factors in the X-ray analysis at 173 K. © 2013 Elsevier B.V.

Supramolecular assemblies of anilinium (Ani(+)) and fluoroanilinium derivatives (FAni(+)) with [18]crown-6 were introduced into electrically conducting [Ni(dmit)(2)] crystals (dmit(2-) is 2-thioxo-1,3-dithiole-4,5-dithiolate). The crystal structures, electrical conductivities, and magnetic susceptibilities of four new crystals of (Ani(+))([18]crown-6)[Ni(dmit)(2)](3) (1), (o-FAni(+))([18]crown-6)[Ni(dmit)(2)](3) (2), (m-FAni(+))([18]crown-6)[Ni(dmit)(2)](3) (3), and (p-FAni(+))([18]crown-6)[Ni(dmit)(2)](3) (4) were examined from the viewpoint of dynamic supramolecular rotator structures within the crystals. The crystal structures, electrical conduction, and magnetic properties were classified into group-I (crystals 1 and 4) and group-II (crystals 2 and 3). The hydrogen-bonding interaction between -NH3+ and the oxygen atoms of [18]crown-6 formed the stand-up configuration of rotator-stator structures of (Ani(+))([18]crown-6) and (FAni(+))([18]crown-6) supramolecules. The potential energy barriers for the 2-fold flip-flop motion of phenyl- and p-fluorophenyl-rings in crystals 1 and 4 had a relatively small magnitude of similar to 150 kJmol(-1), suggesting that rotations of Ani(+) and p-FAni(+) cations around the C-NH3+ axis occurred in the crystals. In contrast, a large magnitude of the potential energy barriers for the rotations of o-FAni(+) and m-FAni(+) cations in crystals 2 and 3 (&gt;600 kJmol(-1)) resulted in static supramolecular cationic structures. The cation:anion ratio of 1:3 in these crystals yielded a trimer pi-stack of [Ni(dmit)(2)] with a semiconductor-like temperature dependence. The magnetic susceptibilities of the static crystals 2 and 3 were reproduced by the one-dimensional antiferromagnetic linear Heisenberg chain through the one-dimensional linear trimer arrangement. The magnetic susceptibilities of dynamic crystals 1 and 4 enhanced electron delocalization through the intratrimer and intertrimer interactions within the trimer stack, where the molecular rotations of Ani(+) and p-FAni(+) cations played an important role.

A Werner-type Cu(II) complex, alpha-[Cu(CF3SO3)(2)(4-mepy)(4)] (alpha-PAC-1-CF3SO3, PAC: porous assembly of coordination complex and 4-mepy: 4-methylpyridine), was synthesized, crystallographically characterized, and its adsorption properties were compared with those of the derivative alpha-[Cu(PF6)(2)(4-mepy)(4)] (alpha-PAC-1-PF6).

The reaction of [Cu(PF6)(2)(py)(4)] (py: pyridine) with [Cu(CH3SO3)(2)(py)(4)], both of which are Werner-type Cu(II) complexes, in a MeOH solution led to the formation of a one-dimensional framework composed of [-{Cu(1)(2)(MeO)(2)}-Cu(2)-Cu(3)-Cu(3)-Cu(2)-] repeating units bridged by inorganic CH3SO3- anions.

A new mixed-anion crystal composed of BEDT-TTF radical cation salt [BEDT-TTF]2(CuBr2)0.4(CuCl2)0.6 with an α&#039;-type donor arrangement with a formal charge of +0.5 per BEDT-TTF was prepared by using a chemical oxidation method and characterized by using X-ray diffraction, four-probe electrical resistivity measurements (semiconductor: ρrt = 2 × 102 Ω cm, Ea = 0.2 eV), and energy band calculations. The results showed that this system had a quasi-one dimensional Fermi surface. © 2011 by the authors; licensee MDPI, Basel, Switzerland.

Sandwich-type hydrogen-bonded supramolecular dications (DAAz(2+))([18]crown-6)(2) and (DAAz(2+)) (dicyclohexane[18]crown-6)(2) (DAAz(2+) = 4,4'-(phenylazophenyl)diammonium) were introduced into [Ni(dmit)(2)](-) anions via a diffusion method to form novel single crystals (DAAz(2+))([18]crown-6)(2)-[Ni(dmit)(2)](2) (1) and (DAAz(2+))(dicyclohexane[18]crown-6)(2)[Ni(dmit)(2)](2) (2), respectively, which were characterized based on their crystal structures and magnetic susceptibilities. The molecular assembly structures and its physical properties were expanded in the use of a three component molecular network system. The two ammonium groups (-NH3+) of the DAAz(2+) dication formed N-H+-O hydrogen-bonding interactions with the oxygen atoms of [18]crown-6 and dicyclohexane[18]crown-6. In the case of crystal 1, an alternating pi-stacking interaction was observed for the [Ni(dmit)(2)](-) anions, whereas orthogonal linear pi-S interactions were detected for crystal 2. Temperature-dependent magnetic susceptibilities of crystals 1 and 2 followed the alternate Heisenberg antiferromagnetic chain (J = -15.8 K) and linear Heisenberg antiferromagnetic chain (J = -13.7 K) models, respectively.