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Comprehensive Summary: The family of [M(dmit)2]‐ salts (dmit2‐ = 2‐thioxo‐1,3‐dithiole‐4,5‐dithiolate; M = Ni, Pd and Pt) generally show novel magnetic, electric, magnetoelectric and photoelectric properties. Herein, a blockwall‐type layered [Me3S][Ni(dmit)2] radical salt (1; Me3S+ = trimethylsulfonium) was prepared and characterized by microanalysis, IR spectroscopy, thermal analysis, powder and single crystal X‐ray diffraction techniques. Salt 1 crystalizes in triclinic space group P‐1, with two pairs of [Ni(dmit)2]‐ and Me3S+ ions in an asymmetric unit. The anions form blockwall‐type monolayer, being parallel to crystallographic (0 1 1) plane, and the cations are accommodated in the spaces of anion monolayer. Salt 1 features a two‐dimensional S = ½ antiferromagnetic (AFM) spin system with θ = ‐97.8(1) K and a semiconductor with σ ≈ 10‐4 S·cm‐1 and activation energy Ea = 0.24(1) eV in 308—368 K. 1 shows two‐step dielectric relaxations ranged from 173—373 K and 1—107 Hz for the dipole motions of two different polar cations. Most importantly, the dielectric constant of 1 reaches to ~17, with high‐κ nature. This study suggests the possibility of achieving high‐κ materials by introducing polar and low rotation barrier components into van der Waals crystal and high‐κ [Ni(dmit)2]‐‐based electrode materials for applications in supercapacitors. [ABSTRACT FROM AUTHOR]

Four new 1D spin-Peierls-type compounds, [D5]1-(4′- R-benzyl)pyridinium bis(maleonitriledithiolato)nickelate ([D5]R-Py; R=F, I, CH3, and NO2), were synthesized and characterized structurally and magnetically. These 1D compounds are isostructural with the corresponding non-deuterated compounds, 1-(4′- R-benzyl)pyridinium bis(maleonitriledithiolato)nickelate (R-Py; R=F, I, CH3, and NO2). Compounds [D5]R-Py and R-Py (R=F, I, CH3, and NO2) crystallize in the monoclinic space group P21/ c with uniform stacks of anions and cations in the high-temperature phase and triclinic space group P $\bar 1$ with dimerized stacks of anions and cations in the low-temperature phase. Similar to the non-deuterated R-Py compounds, a spin-Peierls-type transition occurs at a critical temperature for each [D5]R-Py compound; the magnetic character of the 1D S=1/2 ferromagnetic chain for [D5]F-Py and the 1D S=1/2 Heisenberg antiferromagnetic chain for others appear above the transition temperature. Spin-gap magnetic behavior was observed for all of these compounds below the transition temperature. In comparison to the corresponding R-Py compound, the cell volume is almost unchanged for [D5]F-Py and shows slight expansion for [D5]R-Py (R=I, CH3, and NO2) as well as an increase in the spin-Peierls-type transition temperature for all of these 1D compounds in the order of F>I≈CH3≈NO2. The large isotopic effect of nonmagnetic countercations on the spin-Peierls-type transition critical temperature, TC, can be attributed to the change in ω0 with isotope substitution. [ABSTRACT FROM AUTHOR]

A novel anion-radical salt, (AP)(TCNQ)·HO ( 1), where AP = 4-amino-1-butylpyridin-1-ium and TCNQ = 7,7,8,8-tetracyanoquinodimethane, has been synthesized. X-ray single crystal structural analyses show that the TCNQ anions and AP cations form a well-separated stacking column. The TCNQ anions are uniformly spaced to give a one-dimensional (1-D) chain structure through π···π interactions, which is rarely observed in TCNQ anion-radical system. It is noteworthy that compound 1 shows a peculiar magnetic transition from paramagnetism in the high-temperature (HT) phase to spin gap in low-temperature (LT) phase. Graphical Abstract: A novel anion-radical salt, (AP)(TCNQ)•HO (1), has been synthesized. X-ray single crystal structural analyses show that the TCNQ anions and AP cations form a well-separated stacking column. The TCNQ anions are uniformly spaced to give a one-dimensional (1-D) chain structure through π···π interactions, which is rarely observed in TCNQ anion-radical system.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A new mellitate complex LiMn[C(COO)](HO) ( 1) has been synthesized by the reaction of mellitic acid and Mn(OAc)·4HO in the presence of LiOH·HO. 1 was characterized by the elemental analyses, IR spectra, TGA and the single crystal X-ray diffraction. X-ray crystal structural analysis revealed that the Li cation has a distorted tetrahedral geometry, coordinated by three carboxylic oxygen atoms and one water molecule. The Mn cation is coordinated to one water molecule and five carboxylic oxygen atoms in a slightly distorted octahedral coordination geometry. The mellitate anions behave as a bridging ligand and link six lithium ions and eight manganese ions repeatedly to form an interesting three-dimensional metal–organic coordination polymer. Variable-temperature magnetic susceptibility measurements indicate the presence of antiferromagnetic behavior. Graphical Abstract: A new mellitate complex LiMn[C(COO)](HO) has been synthesized. X-ray crystal structural analysis revealed that the mellitate anions behave as the bridging ligand and link six lithium ions and eight manganese ions repeatedly to form an interesting three-dimensional metal–organic coordination polymer. Its magnetic behavior was studied.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A novel anion-radical salt, (Bbzim)(TCNQ)1.5·CH3CN ( 1), (where Bbzim = 1,3-bis(4-cyanobenzyl)-1H-imidazol-3-ium and TCNQ = 7,7,8,8-tetracyanoquinodimethane) has been fabricated and X-ray single crystal structural analyses. The structure analysis show there exist TCNQ−1 and TCNQ0 entries, which are in agreement with the IR spectra analysis of the compound. Two TCNQ (A) and one TCNQ (B) molecules stack into a triad, and the triads further develop into a column in a pattern ···ABA···ABA··· along a-axis. The temperature dependence of the magnetic susceptibility (2–300 K) for 1 exhibits spin gap of singlet–triplet feature, and the best fit gave the Δ/kB = 1236.5 K. A new anion-radical salt containing TCNQ was prepared, the results of the crystal structure determination shown the radical anions stack into column with triads, and there are two types of TCNQ entries, TCNQ−1 and TCNQ0. The temperature dependence of the magnetic susceptibility for this compound exhibits spin gap of singlet–triplet feature. [ABSTRACT FROM AUTHOR]

The crystal structures and magnetic properties for two ion-pair complexes, [MG][Ni(dmit)2] (1) and [RhB][Ni(dmit)2] (2) (MG+ = N-(4-((4-(dimethylamino)phenyl)(phenyl)methylene)cyclohexa-2,5-dienylidene)-N-methylmethanaminium, RhB+ = 9-(2-carboxyphenyl)-3,6-bis(diethylamino)xanthylium; dmit2- = 1,3-dithiole-2-thione-4,5-dithiolate), have been investigated. Complex 1 crystallizes in the monoclinic space group P21/c, the stacking interactions between the GM+ and [Ni(dmit)2]- lead to the anion exhibiting a banana-shaped molecular geometry; the neighboring anions form a 1-D alternating chain along the crystallographic [1 1 0] direction via intermolecular lateral-to-lateral and head-to-head S ··· S contacts. The temperature dependence of magnetic susceptibility from 2-350 K does not display the magnetic character of a 1-D chain; the magnetic susceptibility data were fit to the Curie-Weiss equation to give C = 0.351(15) emu K mol-1, θ = -3.51(28) K, and χ0 = 8.00(3) × 10-5 emu mol-1. Complex 2 belongs to the triclinic space group P-1 with two crystallographic inequivalent [Ni(dmit)2]- anions, which exhibit perfect planar geometry. Two ethyl groups of RhB+ are disordered over two positions at 296 K, and one becomes ordered at 150 K. The [Ni(dmit)2]- anions form a 2-D molecular layer via intermolecular lateral-to-lateral and head-to-lateral S ··· S interactions with the anionic layer parallel to the crystallographic (0 1 -1) plane. The temperature variation of magnetic susceptibility from 2 to 350 K shows that antiferromagnetic coupling dominates in the anionic layer, and the disorder-order changes of cationic structure are not coupled to magnetic property. [ABSTRACT FROM AUTHOR]

Abstract: Two complexes of [Ni(dmit)2]− (dmit2− =2-thioxo-1,3-dithiole-4,5-dithiolate) with nonmagnetic Schiff base cations, 1-(4-bromobenzylideneamino)pyridinium (4-BrBz-1-APy+; 1) and 1-(3-nitrobenzylideneamino)pyridinium (3-NO2Bz-1-APy+; 2), have been characterized structurally. Their striking structural feature is the deviation of the [Ni(dmit)2]− anion from the square-planar environment around the Ni atom with 11.42° and 6.57° dihedral angles (between the mean molecular planes of two dmit2− ligands) in 1 and 2, respectively. These twists arise from the molecular packing interactions between the superimposed anion and cation. In 1, the magnetic [Ni(dmit)2]− anions are arranged into a wave-shaped regular spin chain, whose magnetism was well fitted by one-dimensional (1D) Heisenberg uniform linear antiferromagnetic chain with |J/k B|=66K. In 2, 1D ladder-shape [Ni(dmit)2]− chains are formed through lateral-to-lateral SS contacts between the adjacent anions, which are further aligned into a two-dimensional (2D) anion layer via van der Waals forces. Complex 2 shows Curie–Weiss-type paramagnetic behavior with Curie constant C =0.421emuKmol−1 and Weiss constant θ =−1.279K. The broken-symmetry DFT approach was utilized to evaluate the magnetic coupling nature for 1 and 2, the theoretical analyses performed at ubpw91/lanl2dz level and concerned the so-called “weak bonding” regime approaches qualitatively explained the magnetic behaviors of 1 and 2. [ABSTRACT FROM AUTHOR]

The synthesis and physico-chemical characterization of an organic-inorganic hybrid material, ( N, N' -bi- n -butyl-4,4′-bipyridinium tetrabromocuprate, has been reported. This hybrid has been characterized using IR, thermogravimetric and single-crystal X-ray diffraction analyses. In the title salt, (C 18 H 26 N 2 )[CuBr 4 ], the CuBr 4 2 − ion shows distorted tetrahedral geometry. The tetrabromocuprate and N, N' -bi- n -butyl-4,4′-bipyridiniums are held together via non-classical C H ⋯ Br hydrogen bond to form a 3-D hybrid structure. The percentages of hydrogen bonding interactions are analyzed by fingerprint plots of Hirshfeld surface. The XPS spectrum exhibits the signals of coexistence of Cu I and Cu II ions. However, the hybrid shows EPR silent behavior at room temperature and variable-temperature magnetic susceptibility displays an isolation of Cu II feature with C = 0.46 emu K mol − 1 and θ approximate to − 0.06 K in 2– K as well. Such a novel nature is further analyzed and discussed. [ABSTRACT FROM AUTHOR]

Abstract: Two novel heterometallic coordination polymers, [AgSm(pydc)2]·2H2O (1) and [AgTb(pydc)2]2·H2O (2) (H2pydc=pyridine-3,4-dicarboxylic acid), have been synthesized under hydrothermal conditions, and characterized by elemental analysis, IR, thermogravimetric analysis and single-crystal X-ray diffraction. Complexes 1 and 2 are isomorphous and exhibit 3D open framework heterometallic coordination polymer containing 1D channels occupied by lattice water molecules. To our knowledge, both compounds represent the rare examples of 3D open-framework 4d–4f heterometallic coordination polymers with open framework structure. Moreover, their luminescent and magnetic properties have also been investigated. [Copyright &y& Elsevier]

Abstract: The reaction of phenyl 2-pyridyl ketoxime (PhPyCNOH) with Cu(NO3)2·3H2O in methanol results in the chiral trinuclear complex [Cu3(OH)(PhPyCNO)3(NO3) (CH3OH)]·(NO3) (1), which has been characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The structure of 1 exhibits a triangle of Cu(II) ions, centered by a triply bridging hydroxo ligand and with three edge-bridging oximate groups from the three PhPyCNO− ions. Preliminary variable-temperature magnetic susceptibility studies reveal an antiferromagnetically-coupled system showing antisymmetric exchange. Complex 1 crystallizes in an acentric space group (P21) that belongs to a polar point group, which displays second harmonic generation response and ferroelectric behavior, and provides a new strategy for designing functional coordination complexes. [Copyright &y& Elsevier]

Nanocrystalline CoxNiyCu100−x−y particles were synthesized by the reduction of metal acetates in a mixture of polyol and Tween 80. Inductively coupled plasma (ICP) analysis revealed that the actual wt% of Co, Ni, and Cu in these nanoparticles was nearly the same as in the starting solutions. The structures of the particles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) spectroscopy, and vibrating sample magnetometry (VSM). The results of XRD and VSM confirmed that there was no metastable alloying in the particles. The particles were composites, consisting of nanoscale crystallites of face-centered cubic (fcc) Cu, face-centered cubic (fcc) Ni, and face-centered cubic (fcc) Co. During preparation the nucleation of Cu occurred first; then small Cu nuclei acted as cores for the precipitation of Co and Ni. The particles showed an increase in saturation magnetization (Ms) as the concentration of Co or Ni in the particles was increased. The changes of both Ms and coercivity of the particles with increasing annealing temperatures were studied. The coercivity of the particles was very high; it could reach as high as 489 Oe for Co34.3Ni31.2Cu34.5. [Copyright &y& Elsevier]

Abstract: A charge-transfer compound, [NO2BzPz][Ni(mnt)2] (NO2BzPz+ =1-(4′-nitrobenzyl)pyrazinium and mnt2− =maleonitriledithiolate), has been structurally characterized, which shows rare noncovalently intermolecular interactions between lone-pair electron and electron-deficient pyrazine rings (NO2⋯π and CN⋯π), theoretical analysis reveals that such intermolecular interactions can be attributed to Coulomb interaction. The paramagnetic [Ni(mnt)2]− anions in [NO2BzPz][Ni(mnt)2] form a dimerized stack and strong antiferromagnetic coupling interaction is observed in such a spin dimer which lead to weak paramagnetic feature in this compound. [Copyright &y& Elsevier]

Zn(en)3Ag2I4 and Ni(en)3Ag2I4, prepared according to the literature, exhibit isomorphic structures (acentrosymmetric space group P63) which are described in detail. [ABSTRACT FROM AUTHOR]

Yellowish rod-like crystals of (Bu4N)[PbI3] are prepared by slow evaporation of a DMF solution containing PbI2 and (Bu4N)I (room temp., 30 d, 66% yield). [ABSTRACT FROM AUTHOR]