Synthesis,crystal structure and electrical properties of [Pd(dmit)2]2− and [Pd(dmit)2]0.5− anion complexes with 2-dimethylamino-1,3-dithiolanylium as counter cation

The synthesis, structural characterization and electrical conductivity measurement of [MDA]₂[Pd(dmit)₂] (1 and [MDA] [Pd(dmit)₂]₂ (2) (MDA = 2-dimethylamino-1,3-dithiolanylium, dmit = 1,3-dithiole-2-thione-4,5-dithiolate) are reported. Complex 1 consists of two Pd(dmit)₂ anions and four MDA cations in the unit cell and the anions are separated by cations in the crystal; the conductivity is about 10⁻⁷ S cm⁻¹. The structure of complex 2 is made of stacked Pd(dmit)₂ dimers. The modes of intra- and inter-dimer molecular overlapping are both of slide-away types. Pd atoms deviate from planes formed by four ligand S atoms 0.07 Å apart to approach each other. Room-temperature conductivity is 10–70 S cm⁻¹. Temperature-dependent conductivity measurement of this compound indicated that it is a semiconductor with a low activation energy (0.043 eV).     

Preparation,crystal structures and electrical conducting properties of new charge-transfer salts: (ET)2·SO3CF3 and (ET)·ClO4

Two new charge-transfer (CT) salts: (ET)₂·SO₃CF₃ and (ET)·ClO₄ were prepared by chemical oxidation of ET with AgSO₃CF₃ and AgClO₄, respectively. Their crystal structures were determined: monoclinic system, Cc, a=35.239(7) Å, b=6.5440(13) Å, c=14.646(3) Å, β=110.26(3)°, V=3168.5(11) Å³ for (ET)₂·SO₃CF₃; monoclinic system, C2/c, a=15.981(3) Å, b=10.627(2) Å, c=11.495(2) Å, β=120.61(3)°, V=1680.2(6) Å³ for (ET)·ClO₄. Electrical conductivity measurements indicate that (ET)₂·SO₃CF₃ shows semi-conducting behaviour with room temperature conductivity of 0.29 S cm⁻¹, while (ET)·ClO₄ is an insulator.     

Strong antiferromagnetic exchange interactions in quasi-one-dimensional (quasi-1D) compounds based on [Pd(mnt)2]− anions: Crystal structures,magnetic properties,and spin dimer analyses

Four ion-pair compounds that are based on the [Pd(mnt)₂]⁻ anion were synthesized and structurally characterized. Crystal structure determinations revealed that, in all four cases, the anions and cations stack as segregated columns, and that adjacent [Pd(mnt)₂]⁻ anions exhibit a strong tendency of dimerization within an anionic column. Values of χ_m(T) in 2–350 K indicated that these compounds are nearly diamagnetic. Results of the spin dimer analyses for the magnetic exchange interactions between the nearest-neighbor spins qualitatively illustrated the magnetic behaviors of these compounds.     

Synthesis,crystal structure and electrical conductivity of [bmim][Ni(dmit)2]3 (bmim = 1-butyl-3-methylimidazolium,dmit = 1,3-dithiol-2-thione-4,5-dithiolate)

A new complex [bmim][Ni(dmit)₂]₃ has been prepared, and its crystal structure and electrical conductivity where determined and measured. Crystallographic parameters for C₂₆H₁₅N₂S₃₀Ni₃: triclinic system; space group: P-1; a=12.760(3), b=19.441(4), c=11.670(2) Å; α=102.00(3), β=117.10(3), γ=95.06(3)°; Z=2, R=0.0579 (I>2σ(I)). The conductivity of this salt at room temperature is 1.7×10⁻² S cm⁻¹ and it shows semiconduction in the temperature range of 110–290 K.     

New bisdithiolene metal complex of the 2-thioxo-1,3-dithiole-4,5-dithiolato(dmit) ligand. Preparation,structure and physical properties

The complex HMEDA[Ni(dmit)₂]₂I (HMEDA=Hexamethylethylenediammonium) has been prepared. A single X-ray crystal structure analysis reveals that there are short S⋯S contacts between Ni(dmit)₂ dimmers. The monoclinic system, space group p2/n, has cell dimensions: a=11.710(3) Å, b=22.559(5) Å, c=7.374(2) Å, β=93.000(3)⁰, V=1945.3(8) ų, z=4. Full-matrix least-squares refinement, based on 2989 reflections converged at R=0.0686. The conductivity of this salt at room temperature is 0.1 S cm⁻¹ and it shows semiconducting behavior from 20 to 300 K.     

Properties of non-aqueous solutions of Ni(CF3SO3)2

The crystals prepared in Ni(CF₃SO₃)₂-CH₃OH and Ni(CF₃SO₃)₂-C₂H₅OH solutions are the solvated compound with four molecules of the respective solvents. The crystals prepared in Ni(CF₃SO₃)₂-CH₃CN, Ni(CF₃SO₃)₂-HCONH₂ and Ni(CF₃SO₃)₂-HCON(CH₃)₂ solutions are the solvated compound with six molecules of the respective solvent.Solvolysis does not take place in Ni(CF₃SO₃)₂-HCONH₂ solution. The apparent molecular volume ø of Ni(CF₃SO₃)₂ in Ni(CF₃SO₃)₂-non-aqueous solution at 30°C is affected by both the solvent and the concentration of Ni(CF₃SO₃)₂ in the solution, and reaches a constant value at a specific concentration of Ni(CF₃SO₃)₂ in each solvent. The constant value of ø becomes lower with increasing maximum electrical conductivity of the solution.It seems that the constant value of ø in Ni(CF₃SO₃)₂-non-aqueous solution is less than 193 cm³ mol^-1.     

Properties of non-aqueous solutions of Zn(CF3SO3)2

Elemental analysis of the crystals produced in the solutions prepared by dissolving a considerable amount of Zn(CF₃SO₃)₂ in the non-aqueous solvents MeOH, EtOH, HCONH₂, CH₃CN and HCON(CH₃)₂ was performed. The crystals obtained from the MeOH and EtOH solutions are the solvated compound with four molecules and those obtained from the HCONH₂, CH₃CN and HCON(CH₃)₂ solutions are the solvated compound with six molecules of the respective solvent.The apparent molecular volume ø of Zn(CF₃SO₃)₂ (zinc salt) in the non-aqueous solutions were determined at 30 °C. ø is affected by both the solvent in the solution and the concentration of the zinc salt. Although ø for the zinc salt in every solvent solution reaches a constant value at or above a specific concentration, the constant value becomes higher with increasing molecular weight of solvent, except for the HCONH₂ solution, and becomes lower with increasing electrical conductivity of the solution, except for the EtOH solution. It seems that the constant value of ø in Zn(CF₃SO₃)₂-non-aqueous solutions is in the range 67 – 175 cm³ mol^-1.     

Efficient electrophosphorescence based on 2-(9,9-diethylfluoren-2-yl)-5-trifluoromethylpyridine iridium complexes

A novel cyclometalated ligand 2-(9,9-diethylfluoren-2-yl)-5-trifluoromethyl-pyridine (fl-5CF₃-py), and its complexes bis[2-(9,9-diethylfluoren-2-yl)-5-trifluoromethyl-pyridinto-C³, N]iridium (acetylacetonate) (fl-5CF₃-py)₂Ir(acac) (5) and bis[2-(9,9-diethylfluoren-2-yl)-5-trifluoromethylpyridinto-C³, N] iridium (2-picolinic acid) (fl-5CF₃-py)₂Ir(pic) (6) were synthesized, respectively. Trifluoromethyl group and 2-picolinic acid were incorporated into iridium ligands to tune luminescent color. Emission spectra of 5 and 6 in THF solutions were 589 and 572 nm. Decomposition temperatures (Td) of 5 and 6 were 326 and 360 °C. Multilayer electrophosphorescent devices were fabricated using 5 and 6 as emitter dopants with electroluminescent spectra maximized at around 585 and 571 nm, respectively. The relatively high efficiencies of the devices and their slow rate of decay against increases in current densities indicated that (fl-5CF₃-py)₂Ir(acac) or (fl-5CF₃-py)₂Ir(pic) was a promising emitter for practical device applications.     

Synthesis,structure of a new acceptor TBA2S6 and preparation,physical properties of ET3S6

A general procedure for the synthesis of the tetrabutylammoium hexasulphide, TBA₂S₆, is first described. The structure of TBA₂S₆ has been determined by X-ray crystallography. Lattice parameters and space group information are as follows: a=15.039(5) Å, b=16.086(5) Å, c=17.078(6) Å, α=β=γ=90.00°, V=4131.5(24) ų, orthorhombic, Pbnb (Z=4). Diffraction data (MoK_α radiation, 2θ_max=50) is collected by Rigaku-AFC6 diffract meter. The structure was solved and refined by direct method and full-matrix least-squares procedures to R-value of 0.0645. The complex ET₃S₆ has been prepared through electrocrystallization ways. The conductivity of this salt at room temperature is 2.3 S cm⁻¹. It shows weak metallic behavior above 240 K. Below this temperature, it becomes a semiconductor. The XPS spectra indicated the presence of three different kinds of S atoms in the salt. The ESR line width is found to be 44.478 G at room temperature.     

Synthesis,crystal structure and thermal behavior of Na4[B10O16(OH)2]·4H2O

New hydrated sodium borate Na₄[B₁₀O₁₆(OH)₂]·4H₂O has been synthesized under mild hydrothermal conditions at 170 °C. The structure was determined by single-crystal X-ray diffraction and further characterized by FT-IR, Raman spectra and DTA-TG. It crystallizes in the monoclinic space group Pc with a unit cell of dimension a = 11.323(2) Å, b = 6.5621(14) Å, c = 12.244(3) Å, α = 90°, β = 91.050(3)°, γ = 90°, V = 909.7(3) Å³, Z = 2. The crystal structure of Na₄[B₁₀O₁₆(OH)₂]·4H₂O consists of Na–O polyhedra and [B₁₀O₁₆(OH)₂]⁴⁻ polyborate anions. Dehydration of this compound occurs in three steps and leads to an amorphous phase which undergoes crystallization.     

Low-dimensional magnetic behaviour of new radical-ion salts: (BEDT-TTF)2[AuIII(i-mnt)2] and (BEDT-TTF)2[BiBr4]

Electrical and magnetic properties of two new radicalion salts of BEDT-TTF (BEDT-TTF is bis(ethylenedithio)-tetrathiafulvalene) are reported. (BEDT-TTF)₂[Au^III(i-mnt)₂] (i-mnt is 1,1-dithio-2,2-dicyano-ethylene) is a semiconductor, σ_r.t. = 2.0 × 10⁻¹−5.5 × 10⁻² S cm⁻¹ with a temperature dependent activation energy (0.14–19 eV). The powder magnetic susceptibility (10–300 K) has been fitted according to a uniform antiferromagnetic (S = 1/2) Heisenberg model by using the experimental g value of 2.0067 and a magnetic exchange constant J/k_B of −110 K. (BEDT-TTF)₂ [BiBr₄] shows similar electrical and magnetic behaviour with σ_r.t. = 5 × 10⁻² S cm⁻¹ on a powdered sample and J/k_B = − 79 K. At low temperature impurities are responsible for the Curie-like behaviour.     

Properties of non-aqueous solutions of Cu(CF3SO3)2

Elemental analysis was made of the crystals produced in solutions prepared by dissolving a considerable amount of Cu(CF₃SO₃)₂ in non-aqueous solvents such as MeOH, EtOH, HCONH₂, CH₃CN and HCON(CH₃)₂. Apart from the crystal produced in the HCONH₂ solution, each crystal is the solvated compound with four molecules of the respective solvent.The apparent molecular volume φ of Cu(CF₃SO₃)₂ in the non-aqueous solutions was determined at 30 °C. φ is affected by the solvent in the solution and the concentration of the copper salt as well. Although φ for the copper salts in every solvent solution reaches a constant value at a specified concentration of the copper salt or higher, the constant value increases with increasing molecular weight of solvent, except for the HCONH₂ solution, and decreases with increasing electrical conductivity of the solution, except for the EtOH solution. It seems that the constant value of φ for non-aqueous solutions of Cu(CF₃SO₃)₂ will be in the range 80 – 200 cm³ mol^-1.     

Radical cation salts of bis (ethylenediseleno) tetrathiafulvalene with halide mercurate anions

Four bis(ethylenediseleno) tetrathiafulvalene (BEDSe-TTF)-based salts, (BEDSe-TTF)₂Hg₂X₂ (X=I. Br), (BEDSe-TTF)₄Hg₃Br₈ · C₂H₃Cl₃ and (BEDSe-TTF)₄Hg₃Br₄ · 1.5C₂H₃Cl₃, have been prepared by electrocrystallization. Two of them. (BEDSe-TTF)₂Hg₂X₆, have been characterized by X-ray crystallography. The triclinic (space group Pī) room-temperature lattice parameters when X=I are: a = 6.798(4),b = 10.728(7), c 15.905(9) Å, α=106.33(6)°, ß=99.78(4)°, γ-92.97(5), V = 1090(1) ų. When X =Br the parameters are: a=6.665(3), b= 10.314(5), c=15.720(7) Å, α-105.70(4)°, ß=99.65(4)°, γ=93.79(4)°, V = 1018(1) ų. At room temperature, (BEDSe-TTF)₄Hg₃Br₈ · C₂H₃Cl₃ is metallic and the others are semiconductors.     

Crystal structures and magnetic properties of iron (III)-based phosphates: Na4NiFe(PO4)3 and Na2Ni2Fe(PO4)3

Crystal structures from two new phosphates Na₄NiFe(PO₄)₃ (I) and Na₂Ni₂Fe(PO₄)₃ (II) have been determined by single crystal X-ray diffraction analysis. Compound (I) crystallizes in a rhombohedral system (S. G: R-3c, Z = 6, a = 8.7350(9) Å, c = 21.643(4) Å, R₁ = 0.041, wR₂=0.120). Compound (II) crystallizes in a monoclinic system (S. G: C2/c, Z = 4, a = 11.729(7) Å, b = 12.433(5) Å, c = 6.431(2) Å, β = 113.66(4)°, R₁ = 0.043, wR₂=0.111). The three-dimensional structure of (I) is closely related to the Nasicon structural type, consisting of corner sharing [(Ni/Fe)O₆] octahedra and [PO₄] tetrahedra forming [NiFe(PO₄)₃]⁴⁺ units which align in chains along the c-axis. The Na⁺ cations fill up trigonal antiprismatic sites within these chains. The crystal structure of (II) belongs to the alluaudite type. Its open framework results from [Ni₂O₁₀] units of edge-sharing [NiO₆] octahedra, which alternate with [FeO₆] octahedra that form infinite chains. Coordination of these chains yields two distinct tunnels in which site Na⁺.The magnetization data of compound (I) reveal antiferromagnetic (AFM) interactions by the onset of deviations from a Curie-Weiss behaviour at low temperature as confirmed by Mössbauer measurements performed at 4.2 K. The corresponding temperature dependence of the reciprocal susceptibility χ⁻¹ follows a typical Curie-Weiss behaviour for T > 105 K. A canted AFM state is proposed for compound (II) below 46 K with a field-induced magnetic transition at H ≈ 19 kOe, revealed in the hysteresis loop measured at 5 K. This transition is most probably associated with a spin-flop transition.     

The Crystal Structure and Phase Transition of Hf2Pt3

The structure of Hf₂Pt₃ has been re-investigated using transmission electron microscopy and Rietveld refinement of neutron powder diffraction data at temperatures up to 1500 °C. This compound does not belong to the MoSi₂ structure type as previously reported, but instead is isostructural with Ti₂Pd₃ and the low-temperature form of Ti₂Ni₃. The crystal structure is orthorhombic (pseudo-tetragonal), Cmcm, Z = 4, with a = 14.653(1) Å, b = 4.8741(3) Å, and c = 4.8671(3) Å at room temperature. The b/c ratio decreases from 1.0014(2) at room temperature to 1.0005(3) at 1500 °C, but the material does not transform to the high-temperature form of Ti₂Ni₃ (I4/mmm) under the conditions studied. The electron diffraction data indicate multiple stacking faults as well as short-range order. On heating above 1630 °C there is a phase transition to a B2-related structure with a ≈ 3.315(1) Å at 1659 °C.     

Synthesis,characterization and nonlinear optical properties of 2-[(E)-2-(4-ethoxyphenyl)ethenyl]-1-methylquinolinium 4-substitutedbenzenesulfonate compounds

In the present investigation, 2-[(E)-2-(4-ethoxyphenyl)ethenyl]-1-methylquinolinium 4-substituted benzenesulfonate (X = CH₃ (1), X = OCH₃ (2), X = Cl (3), X = Br (4)) have been synthesized and characterized by ¹H NMR, UV–Vis and FT-IR spectroscopy methods. In addition compound 3 was also characterized by single crystal X-ray diffraction (XRD) and found that it crystallized out in the monoclinic space group P2₁ with cell parameters, a = 9.8072(9) Å, b = 6.4848(5) Å, c = 19.4405(16) Å, α = 90°, β = 103.421(5)°, γ = 90°, z = 2 and V = 1202.61(17) Å³. The nonlinear optical absorption of the samples has been studied at 532 nm using 5 ns laser pulses, employing the open-aperture z-scan technique. It is found that some of the samples are potential candidates for optical limiting applications.     

Conductive complexes of [Ni(dmid)2] with TTF,TMTTF, and ET

Three charge-transfer salts of [Ni(dmid)₂]⁻ (dmid: 1,3-dithiol-2-one-4,5-dithiolate)—TMTTF[Ni(dmid)₂], TTF_x[Ni(dmid)₂] and ET_x[Ni(dmid)₂] (TMTTF: tetramethyl-tetrathifulvalene, TTF: tetrathifulvalene, ET: bis(ethylenedithio)-tetrathiafulvalene) are prepared and characterized. The TMTTF[Ni(dmid)₂] complex has a structure with mixed packs is formed by cations and anions, which alternate each other with subsequent shift. This compound is semiconductor with the room-temperature conductivity of 2.2 × 10⁻³ Ω⁻¹ cm⁻¹. The TTF_x[Ni(dmid)₂] and ET_x[Ni(dmid)₂] complexes have a highest conductivity: σ_RT 1.86 and 0.54 Ω⁻¹ cm⁻¹, respectively.     

Crystal structure of the new ternary indide CePt2In2 and the isostructural compounds RPt2In2 (R=La,Pr, Nd)

The title compounds have been synthesized by arc melting of the elemental components and subsequent annealing at 870 K. The crystal structure of CePt₂In₂ was determined from single-crystal X-ray data (R=0.0437 for 1439 |F| values and 62 variables). It represents a new structure type of intermetallic compounds: P2₁/m, mP20, a=10.189(6), b=4.477(4), c=10.226(6) Å, β=117.00(5)°, V=416.1(1) ų, Z=4. Isostructural compounds have been found also for La, Pr, and Nd.     

Crystal structure of [NBu4]2[Pd2{C4(COOMe)4}2(μ-OH)2] determined ab initio by charge flipping

The crystal structure of bis(tetra-n-butylammonium)bis(μ₂-hydroxo)-bis(1,2,3,4-tetrakis(methoxycarbonyl)-1,3-butadiene-1,4-diyl)-di-palladium, [NBu₄]₂[Pd₂{C₄(COOMe)₄}₂ (μ-OH)₂], was determined ab initio by X-ray single-crystal diffractometry using the charge flipping method. The compound crystallizes in the monoclinic system with P2₁/c as space group and the following cell parameters: a = 12.8481(6) Å, b = 63.744(3) Å, c = 16.6102(8) Å, β = 111.943(10). The asymmetric unit is formed by two molecules, and the unit cell contains eight molecules (Z = 8) giving a density of 1.369 g cm^?3. The coordination around the Pd(II) atoms is approximately planar, the methoxycarbonyl groups at the α and β positions relative to Pd are perpendicular and parallel to the palladacycle ring, respectively, and the {Pd(μ-O)}₂ core has a bent conformation. The structure closely resembles the features reported previously for other palladacyclopentadiene complexes.     

Synthesis, crystal structures, and optical properties of NaCdPnS3 (Pn = As, Sb)

Two compounds NaCdPnS₃ (Pn = As (1), Sb (2)) were synthesized as transparent yellow and red platelets by reacting cadmium powder with the molten mixtures of Na₂S/As₂S₃/S and Na₂S/Sb/S at 500 °C. Both compounds are plagued with crystal twinning and acceptable crystal structure refinement could only be obtained by identifying the type of the twinning laws. NaCdAsS₃ (1) crystallizes in the monoclinic space group P2₁/n (no. 14) with a = 5.6561(8), b = 16.5487(15), c = 5.6954(8) Å, β = 90.315(11)°, and Z = 4. NaCdSbS₃ (2) crystallizes in the monoclinic space group C2/c (no. 15) with a = 8.1329(6), b = 8.1296(4), c = 17.2600(13) Å, β = 103.499(6)°, and Z = 8. The structures of both compounds feature a ²_∞[CdPnS₃]⁻ layer composed of [CdS₄] tetrahedra and [AsS₃] or [SbS₃] pyramidal units. Between the ²_∞[CdPnS₃]⁻ (Pn = As, Sb) layers the Na⁺ cations reside in a distorted octahedral environment of S atoms. Compound 1 is characterized with UV/Vis diffuse reflectance spectroscopy and IR and Raman spectra.