Structures, energy bands and conductivities of (Me3NEt)[Pd(dmit) 2]2 and (NEt4)[Pd(dmit) 2]2

The electrical conductive molecular crystals (Me₃NEt)[Pd(dmit) ₂]₂ and (NEt₄)[Pd (dmit) ₂]₂ (dmit = 4,5-dimercapto-1,3-dithiole-2-thione) have been prepared, and their crystal structures and conductivity-temperature curves have been determined. The fact that the conductivity at room temperature of (Me₃NEt)[Pd(dmit) ₂]₂ (σ = 58 Ω^-1 cm^-1) is much higher than that of (Net₄)-[Pd(dmit)₂]₂ (σ = 2.2 Ω^-1.cm^-1) has been rationally explained by the results of energy band calculations. (MeNEt₃)[Pd(dmit)₂]₂ belongs to monoclinic system, P2₁/m space group and (Net₄)[Pd (dmit)₂]₂ belongs to triclinic system, space group. The structural conducting component of the crystals is the planar coordinative anion [Pd(dmit)₂]^0.5- which forms the face-to-face dimmer. [Pd(dmit)₂]^- ₂These dimers have been further constructed to be a kind of two-dimensional (2-D) conductive molecular sheet by means of S_S intermolecular interactions. The tiny difference of the above 2-D molecular sheets of the two title crystals has resulted in one order of magnitude difference of conductivities.     

Structures, energy bands and conductivities of (Me_3NEt)[Pd(dmit)_2]_2 and (NEt_4)[Pd(dmit)_2]_2

The electrical conductive molecular crystals (Me3NEt)[Pd(dmit)2]2 and (NEt4)[Pd (dmit)2]2 (dmit = 4,5-dimercapto-1,3-dithiole-2-thione) have been prepared, and their crystal structures and conductivity-temperature curves have been determined. The fact that the conductivity at room temperature of (Me3NEt)[Pd(dmit)2]2 (a = 58 Ω· cm-1) is much higher than that of (NEt4)-[Pd(dmit)2]2(cr= 2.2 Q~1 ?cm'1) has been rationally explained by the results of energy band calculations. (MeNEt3)[Pd(dmit)2]2 belongs to monoclinic system, P21/m space group and (NEt4)[Pd (dmit)2]2 belongs to triclinic system, P1 space group. The structural conducting component of the crystals is the planar coordinative anion [Pd(dmit)2]05- which forms the face-to-face dimmer [Pd(dmit)2]2-. These dimers have been further constructed to be a kind of two-dimensional (2-D)conductive molecular sheet by means of S…S intermolecular interactions. The tiny difference of the above 2-D molecular sheets of the two title crystals has resulted in one     

Two Polymorphs of (Anilinium)(18-Crown-6)[Ni(dmit)2]: Structure and Magnetic Properties

Two polymorphs of monovalent [Ni(dmit)₂]⁻ (dmit²⁻=2-thioxo-1,3-dithiole-4,5-dithiolate) crystals A and B, (anilinium)(18-crown-6)[Ni(dmit)₂], were prepared, and the structure and magnetic properties were investigated. In these crystals, the [Ni(dmit)₂]⁻ molecules form dimers, which arranged into chains between the supramolecular cation structure (anilinium)(18-crown-6). In crystal A, supramolecular cation formed a regular stack, inducing ladder structure of [Ni(dmit)₂], whose magnetism had been well fitted by spin ladder equation with the spin gap of Δ=190 K. Crystal B is ca. 3% more densely packed compared to crystal A. Due to the dense packing, supramolecular cation stack is distorted, which prevented the intermolecular interaction between [Ni(dmit)₂]⁻ dimers in direction corresponds to the ladder-leg direction in crystal A. Reflecting the [Ni(dmit)₂]⁻ arrangement, crystal B showed a temperature dependence of magnetic susceptibility well reproduced by the singlet-triplet thermal activation model, whose antiferromagnetic exchange interaction (2J) was 140 K.     

A New Paramagnetic Pd(dmit)2 Salt: Tris(2,2′-Bipyridine)Nickel(II) Bis(1,3-Dithiole-2-Thione-4,5-Dithiolato)Palladate(II) Mono-Acetonitrile; [Ni(bpy)3][Pd(dmit)2]·CH3CN

Combination of the [Ni(bpy)₃]²⁺ cation complex and the [Pd(dmit)₂]⁻ anion (dmit=C₃S₅²⁻=1,3-dithiole-2thione-4,5-dithiolate) has resulted in the paramagnetic [Ni(bpy)₃][Pd(dmit)₂]·CH₃CN compound, a suitable precursor for a molecular magnetic conductor. Its crystal structure consists of a Pd(dmit)₂ anion arrangement that is quite different from segregated stack layers often found for M(dmit)₂−based compounds. The reduction of the [Pd(dmit)₂]^- to the 2− charged anion in the title compound most probably is the result of a charge disproportionation between Pd(dmit)₂ anions.     

Synthesis,structure, and conductivity of molecular conductor (PyEt)[Ni(dmit)<Subscript>2</Subscript>]<Subscript>2</Subscript>

A new electrical conductive crystal PyEt[Ni(dmit)₂]₂ (dmit = 4,5-dimercapto-1,3-dithiole-2-thione) has been synthesized and its X-ray structure has been determined to be in monoclinic system, C2/c space group. In PyEt[Ni(dmit)₂]₂ crystal, the conducting component [Ni(dmit)₂]^0.5- is face-to-face packed forming molecular column along the c-direction, and these molecular columns are then side-by-side extended along the a-direction forming a kind of two-dimensional conducting sheet on (010). The measured conductivity at room temperature along a certain direction on (010) plane is 10 S · cm^-1. From 282 to 269 K, the crystal shows metallic behavior but changes to semiconductor below 269 K. Based on the measured crystal structure and calculated band structure, this conductor-semiconductor phase transformation can be primarily interpreted: The metallic conductivity is corresponding to the uniform molecular column and the atomic-lattice-chain structure of Ni chain, while the semi-conductive behavior to staggered molecular column and the atomic-zigzag-chain structure of Ni chain.     

Dimethylphosphinato and Dimethylarsinato Complexes of Palladium(II), [Pd(Me2PO2)2]3 and Pd(Me2AsO2)2, and their Adducts

The complexes [Pd(Me₂PO₂)₂]₃ and Pd(Me₂AsO₂)₂ were prepared from the corresponding acids and palladium(II) acetate. Their structures were deduced by IR and NMR spectroscopy. Addition of pyridine and 2,2′‐bipyridine to [Pd(Me₂PO₂)₂]₃ gave the adducts Pd(Me₂PO₂)₂py₂ and Pd(Me₂PO₂)₂bipy, which were characterized by ¹H NMR spectroscopy. Addition of nicotinic acid and nicotinamide in water gave the adducts Pd(Me₂PO₂)₂L₂, whereas in methanol the adducts Pd(Me₂PO₂)₂L were obtained. The cacodylate containing complex formed the adducts Pd(Me₂AsO₂)₂py and Pd(Me₂AsO₂)₂bipy_1/2, which are unstable in CDCl₃. Triphenylphosphine deoxygenated both Pd(Me₂MO₂)₂ complexes, but the palladium(II) containing products could not be isolated. The expected Pd(Me₂P–O)₂ reacted further and gave many products, whereas the anticipated Pd(Me₂As–O)₂ did not bind triphenylphosphine.     

Ethylene polymerization with ansa-metallocene systems rac-(Me2SiOSiMe2)[Ind]2ZrCl2-MAO and rac-(Me2SiOSiMe2)[IndH4]MtCl2-MAO; (Mt = Zr,Ti)

Ethylene was polymerized in toluene using methylalumoxane (MAO) activated rac-(Me₂SiOSiMe₂)[Ind]₂ZrCl₂ ( 1 ) and rac-(Me₂SiOSiMe₂)[IndH₄]₂MtCl₂ (Mt = Zr ( 2 ); Mt = Ti ( 3 )). All three catalyst systems polymerize ethylene with high activity. The molecular weight of polymer produced with zirconocene ( 1 ) was up to a weight-average molecular weight M̄_w = 1.1 × 10⁶ at low polymerization temperature (<20°C) under atmospheric pressure. The titanocene catalyst 3 shows lower activity and produced lower molecular weight polyethylene than zirconocenes 1 and 2. Replacement of aromatic rings in 1 by cyclohexane rings, leading to 2 , increases activity and reduces molecular weight. The catalyst systems show a dependency of the activity on temperature.     

Ni(dmit)2 salts with chiral stilbazolium- and ferrocenyl-based chromophores as countercations

Four 1:1, two-component salts combining the [Ni(dmit)₂]⁻ anion (dmit²⁻ = 2-thioxo-1,3-dithiole-4,5-dithiolato) and chiral stilbazolium-based countercations (HPMS⁺ = 4′-[2-(hydroxymethyl)pyrrolidinyl]-1-methylstilbazolium and MPMS⁺ = 4′-[2-(methoxy-methyl)pyrrolidinyl]-1-methylstilbazolium), or chiral ferrocenyl-based countercations (2⁺ = (E)-1-((R)-2-methylferrocenyl)-2-(1-methyl-4-pyridiniumyl)ethene; 3⁺ = (E)-1-((S)-2-trimethylsilylferrocenyl)-2-(1-methyl-4-pyridiniumyl)ethene) were prepared. Semiconducting behaviour (2·10⁻⁴ S·cm⁻¹ measured on compressed pellets for [Ni(dmit)₂] (MPMS), for example) is secured by the presence of the [Ni(dmit)₂]⁻ anions. The chiral nature of the countercations ensures non-centrosymmetry of the structures (space group P1 for [Ni(dmit)₂](2) and [Ni(dmit)₂](3), for example). A ubiquitous antiparallel arrangement of the cations, which are thus packed in a pseudo-centrosymmetrical environment, results in almost vanishing second-order susceptibilities χ⁽²⁾, and therefore zero efficiencies in second harmonic generation.     

Charge‐Transfer Solids Using Nucleobases: Supramolecular Architectures Composed of Cytosine and [Ni(dmit)2] Assembled by Multiple Hydrogen Bonds and Heteroatomic Contacts

Protonated species of the nucleobase cytosine (C), namely the monoprotonated CH⁺ and the hemiprotonated CHC⁺, were used to obtain four charge‐transfer complexes of [Ni(dmit)₂] (dmit: 1,3‐dithiole‐2‐thione‐4,5‐dithiolate). Diffusion methods afforded two semiconducting [Ni(dmit)₂]^? salts; (CH)[Ni(dmit)₂](CH₃CN) ( 1 ) and (CHC)[Ni(dmit)₂] ( 2 ). In salt 1 , the [Ni(dmit)₂]^? ions with a S=1/2 spin construct a uniform one‐dimensional array along the molecular long axis, and the significant intermolecular interaction along the face‐to‐face direction results in a spin‐singlet ground state. In contrast, salt 2 exhibits the Mott insulating behavior associated with uniform 1D arrays of [Ni(dmit)₂]^?, which assemble a two‐dimensional layer that is sandwiched between the layers of hydrogen‐bonded CHC⁺ ribbons. Multiple hydrogen bonds between CHC⁺ and [Ni(dmit)₂]^? seem to result in the absence of structural phase transition down to 0.5 K. Electrooxidation of [Ni(dmit)₂]^? afforded the polymorphs of the [Ni(dmit)₂]^0.5? salts, (CHC⁺)[{Ni(dmit)₂}^0.5?]₂ ( 3 and 4 ), which are the first mixed‐valence salts of nucleobase cations with metal complex anions. Similar to 2 , salt 3 contains CHC⁺ ribbons that are sandwiched between the 2D [Ni(dmit)₂]^0.5? layers. In the layer, the [Ni(dmit)₂]^0.5? ions form dimers with a S=1/2 spin and the narrow electronic bandwidth causes a semiconducting behavior. In salt 4 , the CHC⁺ units form an unprecedented corrugated 2D sheet, which is sandwiched between the 2D [Ni(dmit)₂]^0.5? layers that involve ring‐over‐atom and spanning overlaps. In contrast to 3 , salt 4 exhibits metallic behavior down to 1.8 K, associated with a wide bandwidth and a 2D Fermi surface. The ability of hydrogen‐bonded CHC⁺ sheets as a template for the anion radical arrangements is demonstrated.     

Towards Single-component Molecular Conductor [Ni(dmit)_2] by Charge Disproportionation:2[Ni(dmit)_2]~(-0.5)[Ni(dmit)_2]+[Ni(dmit)_2]~-

It was commonly thought that a molecular conductor or semiconductor should be composed of at least two components to make the conducting component in partially charged state. However, this idea became questionable by the recent report of the single-component molecular conductor [Ni(tmdt)2]1 as well as several reports about single-component molecular semiconductors such as [Ni(ptdt)2]2 and [Ni(C10H10S8)2]3. In fact, as early as 1985, [Ni(dmit)2] as a by-product in synthesizing TTF[Ni(dmit…     

Synthese und Strukturen von [ReNBr2(Me2PhP)3] und (Me2PhPH)[fac‐Re(NBBr3)Br3(Me2PhP)2]

Syntheses and Structures of [ReNBr₂(Me₂PhP)₃] and (Me₂PhPH)[ fac ‐Re(NBBr₃)Br₃(Me₂PhP)₂] [ReNBr₂(Me₂PhP)₃] ( 1 ) has been prepared by the reaction of [ReNCl₂(Me₂PhP)₃] with Me₃SiBr in dichloromethane. The bromo complex reacts with BBr₃ under formation of [Re(NBBr₃)Br₂(Me₂PhP)₃] ( 2 ) or (Me₂PhPH)[fac‐Re(NBBr₃)Br₃(Me₂PhP)₂] ( 3 ) depending on the experimental conditions. The formation of the nitrido bridge leads to a significant decrease of the structural trans influence of the nitrido ligand which is evident by the shortening of the Re‐(trans)Br bond from 2.795(1) Å in [ReNBr₂(Me₂PhP)₃] to 2.620(1) Å in [fac‐Re(NBBr₃)Br₃(Me₂PhP)₂]^– and 2.598(1) Å in [Re(NBBr₃)Br₂(Me₂PhP)₃], respectively.     

Crystal structures and magnetic properties of (4,4'-phenylazophenyl)diammonium(crown ethers)[Ni(dmit)2]2 crystals

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 (-NH(3)(+)) 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 π-stacking interaction was observed for the [Ni(dmit)(2)](-) anions, whereas orthogonal linear π-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.     

(A19N7)[In4]2 (A = Ca,Sr) and (Ca4N)[In2]: Synthesis,Crystal Structures,Physical Properties,and Chemical Bonding

Single phase powders of (A₁₉N₇)[In₄]₂ (A = Ca, Sr) and (Ca₄N)[In₂] were prepared by reaction of melt beads of the metallic components with nitrogen. The crystal structure of (Ca₁₉N₇)[In₄]₂ was refined based on neutron and X‐ray powder diffraction data. The crystal structure of (Sr₁₉N₇)[In₄]₂ was solved from the X‐ray powder pattern. The structure refinements in combination with results from chemical analyses ascertain the compositions. The compounds (A₁₉N₇)[In₄]₂ (A = Ca, Sr) are isotypes of (Ca₁₉N₇)[Ag₄]₂; (Ca₁₉N₇)[In₄]₂ is probably identical to the earlier reported (Ca_18.5N₇)[In₄]₂. The crystal structure of the isotypes (A₁₉N₇)[In₄]₂ (A = Ca, Sr; cubic, , Ca: a = 1471.65(3) pm; Sr: a = 1561.0(1) pm) contains isolated [In₄] tetrahedra embedded in a framework of edge‐ and vertex‐sharing (A₆N) octahedra. Six of these octahedra are condensed by edge‐sharing around one central A²⁺ ion to form “superoctahedra” (A₁₉N₆) which are connected three‐dimensionally via further octahedra by corner‐sharing. The crystal structure of (Ca₄N)[In₂] (tetragonal, I4₁/amd, a = 491.14(4) pm, c = 2907.7(3) pm) consists of alternating layers of perovskite type slabs of vertex‐sharing octahedra (Ca₂Ca_4/2N) and parallel arranged infinite zigzag chains equation/tex2gif-stack-1.gif[In₂]. In the sense of Zintl‐type counting the compounds (A²⁺)₁₉(N^3?)₇[(In^2.125?)₄]₂ present an electron excess, (Ca²⁺)₄(N^3?)[(In^2.5?)₂] is electron deficient. Metallic properties are supported by electrical resistivity and magnetic susceptibility measurements. The analysis of the electronic structures gives evidence for the existence of homoatomic interactions In–In and significant heteroatomic metal–metal interactions Ca–In which favor the deviations of the title compounds from the (8 – N) rule.     

Synthesis, Structure and Conductivity of （PyH）[Ni（dmit）2]2

A new molecular conductor (PyH)[Ni(dmit)2]2 (dmit = 4, 5-dimercapto-1, 3-dithiole-2-thione) has been prepared and its crystal structure has been determined. Crystallographic parameters for (PyH)[Ni(dmit)2]2: C17H6NNi2S20; triclinic system; P-1 space group; a = 5.9227 (4) , b =8.2279 (6), c = 16.7535 (9) A, a = 90.233 (5) , 0 = 92.107 (6) , y= 104.654 (6) ; V= 789.25 (9) A3; Z = 1; Dc = 2.068 g/cm3; F (000) = 491. The conductivity at one direction on (001) plane at room temperature was measured to be 0.13 ii^-cmf1. The resistivity-temperature curve in the temperature range of 90-290 K shows that this compound behaves as a semiconductor.     

(NPr 4 n )[SRev(S4)(S3CMe 2)]: Ein [SRev(S4)2]−-Derivat

Summary The preparation of (NPr ₄ ⁿ )[SRe(S₄)(S₃CMe ₂)] (1), (NPr ₄ ⁿ )[SRe(S₄)₂] (2), (NBu ₄ ⁿ )[SRe(S₄)₂] (3) and a new modification of (PPh ₄)[SRe(S₄)₂] (4) are reported, including the X-ray structures of1 and4.

Herrn Prof. Dr. A. Meller mit den besten Wünschen zum 60. Geburtstag gewidmet     

Benzene carbon-hydrogen bond activation using Ru(C6Me6)[PH(C6H11(2]H2

The dihydride Ru(C₆Me₆)[PH(C₆H₁₁)₂]H₂ is synthesized in high yield by reducing Ru(C₆Me₆)[PH(C₆H₁₁)₂]Cl₂ with Na[AlH₂(OCH₂CH₂OMe)₂]. In benzene it loses hydrogen under UV irradiation to give Ru(C₆Me₆)[PH(C₆H₁₁(₂]H(C₆H₅).     

Constitutional Isomerism of BiW6Cl15: (BiCl)[W6Cl14] and (BiCl2)[W6Cl13]

The compound (BiCl)[W₆Cl₁₄] was previously characterized as a product of the reduction of tungsten hexachloride with elemental bismuth. Another modification of BiW₆Cl₁₅ is now presented as (BiCl₂)[W₆Cl₁₃], based on the results of an X‐ray single crystal structure determination (space group P2₁/c, a = 1354.3(2) pm, b = 1234.4(2) pm, c = 1538.9(2) pm, and β = 118.76(1) °). The structure of (BiCl₂)[W₆Cl₁₃] contains chains of [(W₆Cl₈ⁱ)Cl₄^aCl_2/2^a–a]^– clusters bridged by chlorine atoms. The (BiCl₂)⁺ counterion exhibits two short Bi–Cl distances of 244.1(4) and 245.9(3) pm, respectively.     

Darstellung,Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalysen von trans-(PNP)[TcCl4(Py)2] und trans-(PNP)[TcBr4(Py)2]

Preparation, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of trans-(PNP)[TcCl₄(Py)₂] and trans-(PNP)[TcBr₄(Py)₂] By reaction of (PNP)₂[TcX₆] with pyridine in the presence of [BH₄]^? (PNP)[TcX₄(Py)₂], X = Cl, Br, are formed. X-ray structure determinations on single crystals of these isotypic Tc^III complexes (monoclinic, space group P2₁/n, Z = 2, for X = Cl: a = 13.676(4), b = 9.102(3), c = 17.144(2) Å, β = 91.159(1)°; for X = Br: a = 13.972(2), b = 9.146(3), c = 17.285(4) Å, β = 90.789(2)°) result in the averaged bond distances Tc? Cl: 2.386, Tc? Br: 2.519, Tc? N: 2.132(3) (X = Cl) and 2.143(4) Å (X = Br). The two pyridine rings are coplanar and vertical to the X? Tc? X-axes, forming angles of 42.28° (X = Cl) and 43.11° (X = Br). Using the molecular parameters of the X-ray structure determination and assuming D_2h point symmetry, the IR and Raman spectra are assigned by normal coordinate analysis based on a modified valence force field. Good agreement between observed and calculated frequencies is obtained with the valence force constants f_d(TcCl) = 1.45, f_d(TcBr) = 1.035, f_d(TcN) = 1.37 (X = Cl) and 1.45 mdyn/ Å (X = Br), respectively.     

Towards Single-component Molecular Conductor [Ni（dmit）2 ] by Charge Disproportionation： 2[Ni（dmit）2]^0.5→[Ni（dmit）2 ]＋ [Ni（dmit）2]^-

A new method of synthesizing single-component molecular conductor [Ni(dmit)2] bythe reaction 2(Me4N)[Ni(dmit)2]2→ [Ni(dmit)2] (Me4N)[Ni(dmit)2] is reported. [Ni(dmit)2]exhibits a semiconductive behavior above 167 K, while from 167 K down to the measuring limit of 60 K, it exhibits metallic conductivity.     

Kristallstrukturen,Schwingungsspektren und Normalkoordinatenanalyse von cis-(Et4N)[OsF2Cl4] und trans-(Ph4P)[OsF2Cl4]

Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of cis -(Et₄N)[OsF₂Cl₄] and trans -(Ph₄P)[OsF₂Cl₄] By oxidation of the pure fluorochloroosmates(IV) with KBrF₄ or PbO₂/trifluoracetic acid in dichloromethane the mixed pentavalent complex anions cis-[OsF₂Cl₄]^– and trans-[OsF₂Cl₄]^– are formed. X-ray structure determinations on single crystals have been performed of cis-(Et₄N) · [OsF₂Cl₄] ( 1 ) (monoclinic, space group P2₁/n, a = 7.519(2), b = 17.648(2), c = 11.942(4) Å, β = 105.98(2)°, Z = 4) and trans-(Ph₄P)[OsF₂Cl₄] ( 2 ) (tetragonal, space group P4/n, a = 12.677(2), c = 7.743(1) Å, Z = 2). Based on the molecular parameters of the X-ray determinations and assuming C_2v point symmetry for the anion of 1 and D_4h point symmetry for the anion of 2 the IR and Raman spectra have been assigned by normal coordinate analysis. Due to the stronger trans influence of chlorine as compared with fluorine for F ^· –Os–Cl′ axes significally different valence force constants are observed in comparison with symmetrically coordinated axes: f_d(OsF ^· ) = 3.35, f_d(OsF) = 3.73, f_d(OsCl′) = 2.05 and f_d(OsCl) with 1.98 and 2.00 mdyn/Å.