Spontaneous Resolution of the Fe(CO) Anion and Inclusion of Chiral Guest Molecules in BEDT-TTF Radical-Cation Salts.

We report the synthesis of three radical-cation salts of BEDT-TTF from racemic tris(oxalato)ferrate by electrocrystallization in the presence of chiral molecules. In the presence of enantiopure l-(+)-tartaric acid, we observe spontaneous resolution of the labile tris(oxalato)ferrate anion to produce the chiral radical-cation salt α-(BEDT-TTF)[Δ-Fe(CO)].[l-(+)-tartaric acid] which contains only the Δ enantiomer of Fe(CO).

Suppression of a Structural Phase Transition by an Orientational Disorder of Counteranions in an Organic Conductor, β″-β″-(BEDT-TTF)ClCHSO.

In 2022, we reported that the β″-(BEDT-TTF)ClCHSO salt () has a phase transition at 210 K on cooling and 260 K on heating, which was suggested as a nondoped-to-doped transition. During the synthesis of , a second salt was coproduced, the structure and properties of which are reported here. The new salt β″-β″-(BEDT-TTF)ClCHSO () has the same composition and is isomorphous to , the low-temperature phase of .

BEDT-TTF radical-cation salts with tris(oxalato)chromate and guest additives.

The family of radical-cation salts β''-(BEDT-TTF)[(A)M(CO)]·guest (M = Fe, Cr, Ga, Al, Co, Mn, Rh, Ru; A = K, HO, NH ) has produced superconductors, metals, semiconductors, and metal-insulators through introduction of different guest molecules into the structure. We present three new additions to the family β''-(BEDT-TTF)[(A)Cr(CO)]·guest with the guest molecules toluene, phenol, or salicylaldehyde. These new guests are liquid or solid additives within the electrocrystallisation medium.

Correlation-driven organic 3D topological insulator with relativistic fermions.

Exploring new topological phenomena and functionalities induced by strong electron correlation has been a central issue in modern condensed-matter physics. One example is a topological insulator (TI) state and its functionality driven by the Coulomb repulsion rather than a spin-orbit coupling. Here, we report a 'correlation-driven' TI state realized in an organic zero-gap system α-(BETS)I.

Porous Mn Magnet with a Pt-Cl Framework: Correlation between Water Vapor Adsorption/Desorption and Slow Magnetic Relaxation.

We report the water adsorption/desorption behavior and dynamic magnetic properties of the Pt-Cl chain complex [{[Pt(en) ][PtCl (en) ]} ][{(MnCl )Cl } ] ⋅ 12H O (1). Upon heating 1 in a vacuum, we obtained the dehydrated form [{[Pt(en) ][PtCl (en) ]} ][{(MnCl )Cl } ] (1DH). The framework structures of 1 and 1DH are identical, and both complexes underwent slow magnetic relaxation.

Melamine-induced synthesis of a structurally perfect kagomé antiferromagnet.

We report here a structurally perfect kagomé lattice {[Cu(bpy)](SiF)(melamine)} (1), where bpy is 4,4'-bipyridine and [SiF] is a hexafluorosilicate anion. In comparison to general 1D linear, 2D layered and 3D cubic metal-organic frameworks, by using Cu nodes and bpy ligands, a perfect kagomé lattice was synthesized by introducing symmetrical melamine molecules. Magnetic susceptibility and low-temperature heat capacity measurements indicated weak antiferromagnetic interactions between the spins and no long-range magnetic ordering to 0.

Chiral metal down to 4.2 K - a BDH-TTP radical-cation salt with spiroboronate anion B(2-chloromandelate).

We report the first example of a chiral BDH-TTP radical-cation salt. Chirality is induced in the structure via the use of a chiral spiroboronate anion where three stereocentres are present, one on each chiral ligand and one on the boron centre. Despite starting from a labile racemic mixture of BS and BR enantiomers, only one enantiomer is present in the crystal lattice.

Electric dipole induced bulk ferromagnetism in dimer Mott molecular compounds.

Magnetic properties of Mott-Hubbard systems are generally dominated by strong antiferromagnetic interactions produced by the Coulomb repulsion of electrons. Although theoretical possibility of a ferromagnetic ground state has been suggested by Nagaoka and Penn as single-hole doping in a Mott insulator, experimental realization has not been reported more than half century. We report the first experimental possibility of such ferromagnetism in a molecular Mott insulator with an extremely light and homogeneous hole-doping in π-electron layers induced by net polarization of counterions.

Single-Crystal-to-Single-Crystal Installation of Ln (OH) Cubanes in an Anionic Metallosupramolecular Framework.

Postsynthetic installation of lanthanide cubanes into a metallosupramolecular framework via a single-crystal-to-single-crystal (SCSC) transformation is presented. Soaking single crystals of K [Rh Zn O(l-cys) ] (K [1]; l-H cys=l-cysteine) in a water/ethanol solution containing Ln(OAc) (Ln =lanthanide ion) results in the exchange of K by Ln with retention of the single crystallinity, producing Ln [1] (2 ) and Ln [Ln (OH) (OAc) (H O) ][1] (3 ) for early and late lanthanides, respectively. While the Ln ions in 2 exist as disordered aqua species, those in 3 form ordered hydroxide-bridged cubane clusters that connect [1] anions in a 3D metal-organic framework through coordination bonds with carboxylate groups.

Chiral molecular conductor with an insulator-metal transition close to room temperature.

Materials exhibiting both chirality and conductivity do not exist in nature and very few examples have been synthesised. We report here the synthesis of a chiral molecular metal which remains metallic down to at least 4.2 K.

2D Molecular Superconductor to Insulator Transition in the β''-(BEDT-TTF)[(HO)(NH)M(CO)]·18-crown-6 Series (M = Rh, Cr, Ru, Ir).

The series of salts β''-(BEDT-TTF)[(HO)(NH)M(CO)]·18-crown-6 show ambient-pressure superconductivity when M = Cr, Rh. Evidence indicates that the previously reported Cr and Rh salts show a bulk Berezinski-Kosterlitz-Thouless superconducting transition. The isostructural ruthenium and iridium salts are reported here.

Mobility of hydrated alkali metal ions in metallosupramolecular ionic crystals.

The design and creation of ionic crystals that show high mobility of ionic species in the solid state has long been a research topic of considerable attention not only due to the practical applications of these materials but also due to the correlation of such ionic species with ion-transport biological systems. In this work, we report the mobility of alkali metal ions (M = Li, Na, K) in the ionic crystals M[RhZnO (l-cysteinate)]·HO (M[]·HO). In M[]·HO, alkali metal ions are distributed in a disordered manner, together with a number of water molecules, within a rigid hydrogen-bonded framework of anionic clusters of [].

Electron Transport in Carbon Nanotubes with Adsorbed Chromium Impurities.

We employ Green's function method for describing multiband models with magnetic impurities and apply the formalism to the problem of chromium impurities adsorbed onto a carbon nanotube. Density functional theory is used to determine the bandstructure, which is then fit to a tight-binding model to allow for the subsequent Green's function description. Electron⁻electron interactions, electron⁻phonon coupling, and disorder scattering are all taken into account (perturbatively) with a theory that involves a cluster extension of the coherent potential approximation.

Control of the Spin Dynamics of Single-Molecule Magnets by using a Quasi One-Dimensional Arrangement.

Magnetic dipole interactions are dominate in quasi one-dimensional (1D) molecular magnetic materials, in which TbNcPc units (Tb =terbium(III) ion, Nc =naphthalocyaninato, Pc =phthalocyaninato) adopt a structure similar to TbPc single-molecule magnets (SMMs). The magnetic properties of the [TbNcPc] (neutral 1 and cationic 2) with 1D structures are significantly different from those of a magnetically diluted sample (3). In particular, the magnetic relaxation time (τ) of 2 in the low-temperature region is five orders of magnitude slower than that of 3.

Dielectric Jump and Negative Electrostriction in Metallosupramolecular Ionic Crystals.

In natural ionic solids, cationic and anionic species are alternately arranged to minimize electrostatic energy. Aggregation of identical ionic species is commonly prohibited due to the repulsive, long-range nature of Coulombic interactions. Recently, we synthesized unique ionic solids, [AuCo(dppe)(D-pen)]X·nHO (dppe = 1,2-bis(diphenylphosphino)ethane, D-pen = D-penicillaminate), in which complex cations are self-assembled into a cationic supramolecular octahedron, while monovalent or divalent inorganic anions are aggregated into an anomalous anionic cluster accommodating several water molecules.

Bulk Kosterlitz-Thouless Type Molecular Superconductor β″-(BEDT-TTF)[(HO)(NH)Cr(CO)]·18-crown-6.

A new molecular superconductor, β″-(BEDT-TTF)[(HO)(NH)Cr(CO)]·18-crown-6, has been synthesized from the organic donor molecule BEDT-TTF with the anion Cr(CO). The crystal structure consists of conducting organic layers of BEDT-TTF molecules which adopt the β″ packing motif (layer A), layers of NH and Λ-Cr(CO) (layer B), layers of (HO)(NH)18-crown-6 (layer C), and layers of NH and Δ-Cr(CO) (layer D) which produce a superstructure with a repeating pattern of ABCDABCDA. As a result of this packing arrangement, this is the 2D superconductor with the widest gap between conducting layers where only a single donor packing motif is present (β″).

Charge and Lattice Fluctuations in Molecule-Based Spin Liquids.

Spin liquid (SL) systems have been the subject of much attention recently, as they have been theoretically predicted to not freeze, even at 0 K. Despite extensive searches being made for such a system, only a few candidates have been found. All of these candidates share geometrical frustrations that are based on triangular lattices.

Molecular conductors from bis(ethylenedithio)tetrathiafulvalene with tris(oxalato)rhodate.

This article reports a family of new radical-cation salts of bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) with tris(oxalato)rhodate: three salts with the formula β''-(BEDT-TTF)[(cation)Rh(CO)]·solvent (solvent = fluorobenzene, chlorobenzene, or bromobenzene) and one with the formula pseudo-κ-(BEDT-TTF)[(NH)Rh(CO)]·benzonitrile. We report here the syntheses, crystal structures, electrical properties and Raman spectroscopy of these new molecular conductors. The bromobenzene salt shows a decrease in resistivity below 2.

Ambient-pressure molecular superconductor with a superlattice containing layers of tris(oxalato)rhodate enantiomers and 18-crown-6.

We report a novel multilayered organic-inorganic hybrid material, β″-(BEDT-TTF)[(HO)(NH)Rh(CO)]·18-crown-6. This is the first molecular superconductor to have a superlattice with layers of both BEDT-TTF and 18-crown-6 and also the first with the anion tris(oxalato)rhodate. This is the 2D superconductor with the widest gap between conducting layers, where only a single donor packing motif is observed (β″).

Enantiopure and racemic radical-cation salts of B(malate)2(-) anions with BEDT-TTF.

We have synthesized the first examples of radical-cation salts of BEDT-TTF with chiral borate anions, [B(malate)2](-), prepared from either enantiopure or racemic bidentate malate ligands. In the former case only one of two diastereoisomers of the borate anion is incorporated, while for the hydrated racemic salt one racemic pair of borate anions containing a R and a S malate ligand is incorporated. Their conducting and magnetic properties are reported.

Transitions in pressure collapsed clathrate hydrates.

Type II clathrate hydrates (CHs), or ice clathrates, are inclusion compounds in which a hydrogen-bonded cage-like structure of H2O accommodates molecules of suitable size, known as "guest molecules". CHs have similar local geometrical arrangements of the hydrogen-bonded water network as ice and both are known to collapse to amorphous states on isothermal pressurization at temperatures below about 140 K. Moreover, the collapsed CH states undergo a glass, or glass-like, transition at 140 K on heating at 1 GPa, which is identical to that of collapsed ice, or high density amorphous ice.

Thermodynamic investigation by heat capacity measurements of ferrimagnetic A2Mn[Mn(CN)6] (A=K, Rb, Cs) Prussian blue compounds.

Heat capacity measurements of a new series of Prussian blue analogs of A2Mn[Mn(CN)6] (A=K, Rb, Cs) composition were performed using thermal relaxation calorimetry. The Cs compound has a face-centered cubic structure with a linear Mn-C≡N-Mn linkage, while the monoclinic Rb and K compounds have nonlinear Mn-C≡N-Mn linkages. For all of the compounds, large broad thermal anomalies associated with magnetic transitions were observed in the temperature dependence of the heat capacity.

Electronic state of a conducting single molecule magnet based on Mn-salen type and Ni-dithiolene complexes.

The electrochemical oxidation of an acetone solution containing [Mn(III) (5-MeOsaltmen)(H(2)O)](2)(PF(6))(2) (5-MeOsaltmen(2-) = N,N'-(1,1,2,2-tetramethylethylene)bis(5-methoxysalicylideneiminate)) and (NBu(4))[Ni(dmit)(2)] (dmit(2-) = 2-thioxo-1,3-dithiole-4,5-dithiolate) afforded a hybrid material, [Mn(5-MeOsaltmen)(acetone)](2)[Ni(dmit)(2)](6) (1), in which [Mn(2)](2+) single-molecule magnets (SMMs) with an S(T) = 4 ground state and [Ni(dmit)(2)](n-) molecules in a charge-ordered state (n = 0 or 1) are assembled in a layer-by-layer structure. Compound 1 crystallizes in the triclinic space group P1 with an inversion center at the midpoint of the Mn···Mn dimer. The [Mn(2)](2+) unit has a typical nonplanar Mn(III) dimeric core and is structurally consistent with previously reported [Mn(2)] SMMs.