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1.
The intermetalloid clusters [M2Bi12]4+ (M = Ni, Rh) were synthesized as halogenido‐aluminates in Lewis‐acidic ionic liquids. The reaction of bismuth and NiCl2 in [BMIm]Cl · 5AlCl3 (BMIm = 1‐butyl‐3‐methylimidazolium) at 180 °C yielded black, triclinic (P1 ) crystals of [Ni2Bi12][AlCl4]3[Al2Cl7]. Black, monoclinic (P21/m) crystals of [Rh2Bi12][AlBr4]4 precipitated after dissolving the cluster salt Bi12–xRhX13–x (X = Cl, Br; 0 < x < 1) in [BMIm]Br·4.1AlBr3 at 140 °C. In the cationic cluster [Ni2Bi12]4+, the nickel atoms center two base‐sharing square antiprisms of bismuth atoms (symmetry close to D4h). The valence‐electron‐poorer rhodium‐containing cluster is a distorted variant of this motif: the terminating Bi4 rings are folded to bicyclic “butterflies“ and the central square splits into two dumbbells (symmetry close to D2h). DFT‐based calculations and real‐space bonding analyses place the intermetalloid units between a triple‐decker complex and a conjoined Wade‐Mingos cluster.  相似文献   

2.
Two polymorphs of the new cluster compound [Ru2Bi14Br4](AlCl4)4 have been synthesized from Bi24Ru3Br20 in the Lewis acidic ionic liquid [BMIM]Cl/AlCl3 ([BMIM]+: 1‐n‐butyl‐3‐methylimidazolium) at 140 °C. A large fragment of the precursor’s structure, namely the [(Bi8)Ru(Bi4Br4)Ru(Bi5)]5+ cluster, dissolved as a whole and transformed into a closely related symmetrical [(Bi5)Ru(Bi4Br4)Ru(Bi5)]4+ cluster through structural conversion of a coordinating Bi82+ to a Bi5+ polycation, while the remainder was left intact. Both modifications have monoclinic unit cells that comprise two formula units (α form: P21/n, a=982.8(2), b=1793.2(4), c=1472.0(3) pm, β=109.05(3)°; β form: P21/n, a=1163.8(2), b=1442.7(3), c=1500.7(3), β=97.73(3)°). The [Ru2Bi14Br4]4+ cluster can be regarded as a binuclear inorganic complex of two ruthenium(I) cations that are coordinated by terminal Bi5+ square pyramids and a central Bi4Br4 ring. The presence of a covalent Ru? Ru bond was established by molecular quantum chemical calculations utilizing real‐space bonding indicator ELI‐D. Structural similarity of the new and parent cluster suggests a structural reorganization or an exchange of the bismuth polycations as mechanisms of cluster formation. In this top‐down approach a complex‐structured unit formed at high temperature was made available for low‐temperature use.  相似文献   

3.
Synthesis and Crystal Structures of Bismuth Chalcogenolato Compounds Bi(SC6H5)3, Bi(SeC6H5)3, and Bi(S‐4‐CH3C6H4)3 Bismuth(III) acetate reacts with thiophenol in ethyl alcohol at 80 °C to yield Bi(SC6H5)3 ( 1 ). Slow cool down of the deep yellow mixture lead to the formation of orange crystals of 1 . The homotype phenylselenolato compound of bismuth Bi(SeC6H5)3 ( 2 ) has been prepared by the reaction of BiX3 (X = Cl, Br) with Se(C6H5)SiMe3 in diethyl ether. In the same way as Bi(SC6H5)3 ( 1 ) the reaction between bismuth(III) acetate and 4‐tolulenethiole results in red crystals of Bi(S‐4‐CH3C6H4)3 ( 3 ). In consideration of three longer Bi–E distances (intermolecular interactions, E = S; Se) the Bi(EPh)3 molecules form via face‐linked octahedra 1‐dimensional chains in the crystal lattice, while for 3 the 1‐dimensional chain is formed by face‐linked trigonal prisma. We reported herein the synthesis and structures of Bi(SC6H5)3 ( 1 ), Bi(SeC6H5)3 ( 2 ), and Bi(S‐4‐CH3C6H4)3 ( 3 ).  相似文献   

4.
An innovative soft chemical approach was applied, using ionic liquids as an alternative reaction medium for the synthesis of tellurium polycationic cluster compounds at room temperature. [Mo2Te12]I6, Te6[WOCl4]2, and Te4[AlCl4]2 were isolated from the ionic liquid [BMIM]Cl/AlCl3 ([BMIM]+: 1‐n‐butyl‐3‐methylimidazolium) and characterized. Black, cube‐shaped crystals of [Mo2Te12]I6, which is not accessible by conventional chemical transport reaction, were obtained by reaction of the elements at room temperature in [BMIM]Cl/AlCl3. The monoclinic structure (P21/n, a = 1138.92(2) pm, b = 1628.13(2) pm, c = 1611.05(2) pm, β = 105.88(1) °) is homeotypic to the triclinic bromide [Mo2Te12]Br6. In the binulear complex [Mo2Te12]6+, the molybdenum(III) atoms are η4‐coordinated by terminal Te42+ rings and two bridging η2‐Te22– dumbbells. Despite the short Mo···Mo distance of 297.16(5) pm, coupling of the magnetic moments is not observed. The paramagnetic moment of 3.53 μB per molybdenum(III) atom corresponds to an electron count of seventeen. Black crystals of monoclinic Te6[WOCl4]2 are obtained by the oxidation of tellurium with WOCl4 in [BMIM]Cl/AlCl3. Tellurium and tellurium(IV) synproportionate in the ionic liquid at room temperature yielding violet crystals of orthorhombic Te4[AlCl4]2.  相似文献   

5.
In this paper, the effect of ionic liquids on the CaCO3 crystal growth has been studied for the first time. The obtained CaCO3 crystals were charactcred by the X-ray diffraction and scanning electron micrographs. The results showed that the control ability of ionic liquids for CaCO3 crystals growth was dependent on the counter anion very much.  相似文献   

6.
Syntheses, Properties and Crystal Structures of the Cluster Salts Bi6[PtBi6Cl12] and Bi2/3[PtBi6Cl12] Melting reactions of Bi with Pt and BiCl3 yield shiny black, air insensitive crystals of the subchlorides Bi6[PtBi6Cl12] and Bi2/3[PtBi6Cl12]. Despite the substantial difference in the bismuth content the two compounds have almost the same pseudo‐cubic unit cell and follow the structural principle of a CsCl type cluster salt. Bi6[PtBi6Cl12] consists of cuboctahedral [PtBi6Cl12]2? clusters and Bi62+ polycations (a = 9.052(2) Å, α = 89.88(2)°, space group P 1, multiple twins). In the electron precise cluster anion, the Pt atom (18 electron count) centers an octahedron of Bi atoms whose edges are bridged by chlorine atoms. The Bi62+ cation, a nido cluster with 16 skeletal electrons, has the shape of a distorted octahedron with an opened edge. In Bi2/3[PtBi6Cl12] the anion charge is compensated by weakly coordinating Bi3+ cations which are distributed statistically over two crystallographic positions (a = 9.048(2) Å, α = 90.44(3)°, space group ). Bi6[PtBi6Cl12] is a semiconductor with a band gap of about 0.1 eV. The compound is diamagnetic at room temperature though a small paramagnetic contribution appears towards lower temperature.  相似文献   

7.
Bi53+ Polycations in Ordered and Plastic Crystals of Bi5[AlI4]3 and Bi5[AlBr4]3 Dark‐red air‐sensitive crystals of pentabismuth‐tris(tetrabromoaluminate) Bi5[AlBr4]3 and black crystals of Bi5[AlI4]3 have been crystallized from melts of Bi, BiX3 and AlX3 (X = Br, I). X‐ray diffraction on a single crystal of Bi5[AlI4]3 (T = 293(2) K; space group Pnma; a = 2143.6(3) pm, b = 1889.1(1) pm, c = 811.74(5) pm) revealed an ordered packing of Bi53+ trigonal bipyramids and [AlI4]? tetrahedra that corresponds to the PuBr3 structure type. Contrary to the so far known Bi53+ polycations with accurate D3h symmetry, the bismuth cluster found in Bi5[AlI4]3 holds only Cs symmetry. The room temperature structure of the tetrabromoaluminate Bi5[AlBr4]3, which is related to the AuCu3 type, shows a dynamic disorder of the Bi53+ polycations (T = 293(2) K; space group ; a = 1766.2(3) pm). Slight cooling induces the transition into an ordered rhombohedral phase isostructural to Bi5[AlCl4]3 (T = 260(2) K; space group a = 1241.5(8) pm, c = 3041(2) pm).  相似文献   

8.
Bi37InBr48: a Polar Subhalide with Bi95+ Polycations, Complex Bromobismuthate(III) Anions [Bi3Br13]4— and [Bi7Br30]9—, and Pentabromoindate(III) Anions [InBr5]2— Black crystals of Bi37InBr48 were synthesized from bismuth, indium and BiBr3 by cooling stoichiometric melts from 570 K to 470 K. X‐ray diffraction on powders and single‐crystals revealed that the compound crystallizes with space group P 63 (a = 2262.6(4); c = 1305.6(2) pm). The Bi95+ polycations in the polar crystal structure have the shape of heavily distorted tri‐capped trigonal prisms with approximate Cs symmetry. The high complexity of the structure results from three coexisting types of anionic groups: Three edge‐sharing [BiBr6] octahedra constitute the trigonal bromobismuthate(III) anion [Bi3Br13]4—. Four [BiBr6] and three [BiBr5] polyhedra share common vertices to form the [Bi7Br30]9— hemi‐sphere, in which the trigonal bipyramid of the pentabromoindat(III) ion [InBr5]2— is embedded.  相似文献   

9.
Synthesis of ionic liquids (IL) based on oxygen‐containing spirobipyrrolidinium salts with BF4, BF3C2F5, and NTf2 as counterions was undertaken. Their physical and electrochemical properties were evaluated for suitability for Room Temperature Ionic Liquids (RTIL) application. Reduction in melting point occurred upon exchange of C(2) by an O‐atom of spirobipyrrolidinium, without sacrificing the electrochemical stability; while introduction of alkyl groups between the N‐ and O‐atoms led to incorporation of asymmetry, and hence reduced the melting points, and viscosity.  相似文献   

10.
A series of cyclopenta[b]chromen‐1(9H)‐one derivatives is prepared in high yields by a one‐pot reaction of substituted salicylaldehydes and cyclopentane‐1,3‐dione in ionic liquids of [BMIm]Br, the procedure is very mild and environmentally benign.  相似文献   

11.
A series of nitrile‐functionalized ionic liquids were found to exhibit temperature‐dependent miscibility (thermomorphism) with the lower alcohols. Their coordinating abilities toward cobalt(II) ions were investigated through the dissolution process of cobalt(II) bis(trifluoromethylsulfonyl)imide and were found to depend on the donor abilities of the nitrile group. The crystal structures of the cobalt(II) solvates [Co(C1C1CNPyr)2(Tf2N)4] and [Co(C1C2CNPyr)6][Tf2N]8, which were isolated from ionic‐liquid solutions, gave an insight into the coordination chemistry of functionalized ionic liquids. Smooth layers of cobalt metal could be obtained by electrodeposition of the cobalt‐containing ionic liquids.  相似文献   

12.
The phase behaviour of binary mixtures of ionic surfactants (1‐alkyl‐3‐imidazolium chloride, CnmimCl with n=14, 16 and 18) and imidazolium‐based ionic liquids (1‐alkyl‐3‐methylimidazolium tetrachloroferrate, CnmimFeCl4, with n=2 and 4) over a broad temperature range and the complete range of compositions is described. By using many complementary methods including differential scanning calorimetry (DSC), polarised microscopy, small‐angle neutron and X‐ray scattering (SANS/SAXS), and surface tension, the ability of this model system to support self‐assembly is described quantitatively and this behaviour is compared with common water systems. The existence of micelles swollen by the solvent can be deduced from SANS experiments and represent a possible model for aggregates, which has barely been considered for ionic‐liquid systems until now, and can be ascribed to the rather low solvophobicity of the surfactants. Our investigation shows that, in general, CnmimCl is a rather weak amphiphile in these ionic liquids. The amphiphilic strength increases systematically with the length of the alkyl chain, as seen from the phase behaviour, the critical micelle concentration, and also the level of definition of the aggregates formed.  相似文献   

13.
Electrode‐dependent potential windows (see picture, GC=glassy carbon) are determined for five dialkylammonium carbamate (dialcarb) room‐temperature ionic liquids in a systematic study of their physical and electrochemical properties. The viscosity and conductivity of the dialcarb ionic liquids, which are “distillable” at low temperature, are comparable to those of some conventional room‐temperature ionic liquids.

  相似文献   


14.
New salts based on imidazolium, pyrrolidinium, phosphonium, guanidinium, and ammonium cations together with the 5‐cyanotetrazolide anion [C2N5]? are reported. Depending on the nature of cation–anion interactions, characterized by XRD, the ionic liquids (ILs) have a low viscosity and are liquid at room temperature or have higher melting temperatures. Thermogravimetric analysis, cyclic voltammetry, viscosimetry, and impedance spectroscopy display a thermal stability up to 230 °C, an electrochemical window of 4.5 V, a viscosity of 25 mPa s at 20 °C, and an ionic conductivity of 5.4 mS cm?1 at 20 °C for the IL 1‐butyl‐1‐methylpyrrolidinium 5‐cyanotetrazolide [BMPyr][C2N5]. On the basis of these results, the synthesized compounds are promising electrolytes for lithium‐ion batteries.  相似文献   

15.
The synthesis, structure, and physical properties of ionic liquids (IL) bearing the novel [Al(O–C6H4–CN)4] ion as counterion to the commonly used [NR4]+, [PR4]+ and imidazolium ions are reported. Both the influence of the alkyl chain length as well as the functionalization with cyano groups is studied. These ILs are easily obtained by reaction of Ag[Al(O–C6H4–CN)4] with the corresponding ammonium, phosphonium, and imidazolium halides. The stability towards electrophilic cations was investigated. All prepared salts have a window for the liquid phase of ca. 200 °C and are thermally stable up to 450 °C. The solid‐state structures reveal only weak cation ··· anion and anion ··· anion interactions in accord with the observed low melting points (glass transition points).  相似文献   

16.
聚离子液体的合成及应用   总被引:1,自引:0,他引:1  
聚离子液体(PILs)是在重复单元上具有阴、阳离子电解质基团的聚合物。此类聚合物结合了离子液体和聚合物的一些性质,近年来在高分子化学和材料科学等领域受到广泛关注。本文将聚离子液体划分为聚阳离子型离子液体、聚阴离子型离子液体、聚两性型离子液体和共聚型离子液体四类并介绍了聚离子液体的性质及各类聚离子液体的合成。此外,本文还对聚离子液体在有机分散剂、纳米复合材料、电化学、吸附剂和分离等方面的应用进行了综述。  相似文献   

17.
Summary: Polyurea with exotic porous structures has been synthesized by the interfacial polymerization between hexane and a series of 1‐alkyl‐3‐methylimidazolium room‐temperature ionic liquids (ILs). Scanning electron microscopy micrographs of the polyurea show a macroporous morphology of aggregated polymer particles with sizes around 200 nm and pore sizes between 100 to 500 nm. The geometry of the polymer particles and the pore size vary with the ILs employed. X‐Ray diffraction shows ionic‐liquid‐induced suppression of 3D crystalline order in the polyurea products. The microstructures of the polymer together with the FT‐IR results suggest that the observed exotic polymer morphology originates from interactions between the ionic liquid and the polymer.

SEM micrograph of the interconnected macroporous structure of the polyurea formed in [C2mim][BF4] ionic liquid. The scale bar is 100 nm.  相似文献   


18.
总结了近年来在离子液体中制备金属氧化物纳米材料的新方法以及离子液体在金属氧化物纳米材料制备方面的应用及发展趋势.目前,对于制备纳米金属氧化物,离子液体主要是作为电解液、表面活性剂;其未来的发展趋势是离子热合成和集模板-溶剂-反应物于一身的离子液体反应.  相似文献   

19.
The compound Bi(TeSitBu2Ph)3 ( 1 ) was obtained from the reaction of BiCl3 with tBu2PhSiTeSiMe3 in diethyl ether. The single crystal structure analysis revealed a trigonal pyramidal structure of the BiTe3 core and weak Bi···C(arene) contacts. Compound 1 was characterized by multinuclear NMR spectroscopy, IR spectroscopy and elemental analysis. Thermogravimetric experiments show that compound 1 decomposes with formation of Bi2Te3 or a mixture of elemental bismuth and Bi4Te3, depending on the pressure conditions.  相似文献   

20.
The Cluster Salts Bi14Si2MI12 (M = Rh, Ir): [Bi8Si2] and [MBi6I12] Building Groups in CsCl‐like Structure The reaction of bismuth and iridium with iodine in evacuated quartz ampoules at 1320 K yields black, air insensitive crystals of Bi14Si2IrI12. The silicon therein is abstracted from the ampoule material whereby the oxygen is gettered in BiOI. The synthesis of Bi14Si2RhI12 requires the addition of niobium, which gives NbOI2 with the oxygen originating from the SiO2. X‐ray diffraction on single crystals showed that the two isotypic compounds crystallize in the space groups P 4/m c c with a = 1018.3(1), c = 2020.1(4) pm for M = Ir, and a = 1019.0(1), c = 2018.7(4) pm for M = Rh. The crystal structures consist of two types of isolated clusters, which form a CsCl‐like packing. In the [MBi6I12] cuboctahedron the central transition metal atom is octahedrally surrounded by bismuth atoms, and the iodine atoms bridge the edges of the octahedron. The [Bi8Si2] polyhedron is a tetragonal antiprism of bismuth atoms of which square faces are capped by silicon atoms. Based on crystal chemistry and band structure calculations the compounds may be formulated as cluster salts [Bi8Si2]3+[MBi6I12]3–. Measurements of the electrical conductivity showed that Bi14Si2IrI12 is a semiconductor with a band gap of about 0.1 eV. A single unpaired electron out of 1903 electrons per formula causes paramagnetic behaviour that is superposed by strong diamagnetic contributions.  相似文献   

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