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1.
New Complexes of Titanium with Bis(trimethylsilyl)amido Ligands The reaction of cp′TiCl3 with LiN(SiMe3)2 · Et2O 1 yield the compounds cp′TiCl2N(SiMe3)2 (cp′ = C5H5 2 , C5H4SiMe3 3 , C5H3(SiMe3)2 4 , C5Me5 5 ) and cp′TiCl[N(SiMe3)2]2 (cp′ = C5H5 6 ). Compound 2 was characterized by an X-ray structural analysis with space group P21/n and unit cell dimensions of a = 1 660.9(7), b = 688.6(3), c = 1 739.1(8) pm and β = 117.18(3)°. 相似文献
2.
Nils Wiberg 《Angewandte Chemie (International ed. in English)》1971,10(6):374-387
The highly reactive compound bis(trimethylsilyl)diimine (BSD), which was first prepared by oxidation of lithium tris(trimethylsilyl)hydrazide, is light blue, sensitive to thermolysis and hydrolysis, and ignites spontaneously in air. On the basis of electron transfer, acid-base, or free-radical reactions, it acts in particular as a (preparatively useful) redox system and as an agent for the introduction of azo groups. Redox reactions lead by oxidation or reduction of the other reactant through two oxidation stages to hydrazine derivatives or molecular nitrogen, and in the case of electrochemical reduction, to BSD radical-anions. Azo-group transfers, on the other hand, yield new inorganic azo compounds with no change in the oxidation state of the diimine group. 相似文献
3.
Reactions of some Methylmetal Halides of Aluminium, Gallium, and Indium with Hexamethyldisilazane MeAlCl2 or MeGaBr2, and bis(trimethylsilyl)amine form the dimeric, mixed-substituted ring molecules (Me(Hal)MIII–N(H)SiMe3)2 and one equivalent Me3SiHal. The NMR (1H, 13C, 29Si) and vibrational spectra (IR, Raman) are measured and the X-ray structure analysis of the compound with MIII = Al and Hal = Cl, has been done as well. Me2AlCl with an excess of HN(SiMe3)2 forms the expected amide (Me2Al–N(H)SiMe3)2, the homologue Me2GaCl with HMDS, however, gives at 50–55 °C only the cyclic (1 : 1) adduct (Me2Ga–N(H)SiMe3) · (Me2GaCl). This complex crystallizes in the space group Cmc21, the unit cell consists of four binucleate molecules with folded Ga–N–Ga–Cl-ring skeletons. 相似文献
4.
Antimony(III)-butoxo Compounds Tri(tert.-butoxo)stiban 1 reacts with antimony(III) chloride dependent from the molar ratio to yield Sb(OtBu)2Cl 2 and Sb4Cl7O(OtBu)3 3 resp ‥ 3 are discrete molecules with a cage structure. 2 is associated by oxygen bridges. The vibrational spectra of 1–3 are assigned. 相似文献
5.
Syntheses and Properties of Bis(perfluoroalkyl)zinc Compounds The conditions for the syntheses of bis(perfluoroalkyl)zinc compounds Zn(Rf)2 · 2 D (Rf = C2F5, n‐C3F7, i‐C3F7, n‐C4F9, n‐C6F13, n‐C7F15, and n‐C8F17; D = CH3CN, tetrahydrofurane, dimethylsulfoxide) are described. Mass spectra, thermal decompositions, 19F‐ and 13C‐NMR spectra are discussed. 相似文献
6.
Chemistry of Polyfunctional Molecules. 124. Silver(I) Complexes Containing the Ligands Bis(diphenylphosphanyl)amine, -amide and Tris(diphenylphosphanyl)amine Bis(diphenylphosphanyl)amine HN(PPh2)2 ( 1 ) reacts with AgCl to the complex HN(PPh2AgCl)2 ( 5 ) for which in the solid state the cluster structure Ag4Cl4[HN(PPh2)2]2 is assumed. Reaction of 5 with LiN(PPh2)2 ( 2 ) gives the known [N(PPh2AgPh2P)2N] ( 8 ) and the new complex [Ag(μ—Ph2PNPPh2)2(μ—Ph2PNHPPh2)Ag] · dioxane ( 7 · dioxane). The compound 7 · dioxane has been characterized by X-ray diffraction. The molecules are found to contain a bicyclo[3.3.3]undecane-type structure with trigonal planar coordinated silver atoms, which are separated by 281,6(1) pm. The dioxane is bound via H-bridge bond to the NH group of the coordinated HN(PPh2)2. Treatment of 8 with ClPPh2 yields N(PPh2AgCl)3 ( 12 ), which has also been obtained by the reaction of N(PPh2)3 ( 3 ) with silver chloride. All the compounds have been characterized, so far as possible, by IR, Raman, 1H NMR, 31P{1H} NMR, 13C{1H} NMR and mass spectroscopy. 相似文献
7.
Matthias Westerhausen Manfred Hartmann Arno Pfitzner Wolfgang Schwarz 《无机化学与普通化学杂志》1995,621(5):837-850
Bis(trimethylsilyl)amides and -methanides of Yttrium — Molecular Structures of Tris(diethylether-O)lithium-(μ-chloro)-tris[bis(trimethylsilyl)methyl]yttriate, solvent-free Yttrium Tris[bis(trimethylsilyl)amide] as well as the Bis(benzonitrile) Complex The reaction of yttrium(III) chloride with the three-fold molar amount of LiE(SiMe3)2 (E = N, CH) yields the corresponding yttrium derivatives. Yttrium tris-[bis(trimethylsilyl)amide] crystallizes in the space group P3 1c with a = 1 636,3(2), c = 849,3(2) pm, Z = 2. The yttrium atom is surrounded trigonal pyramidal by three nitrogen atoms with Y? N-bond lengths of 222 pm. Benzene molecules are incorporated parallel to the c-axes. The compound with E = CH crystallizes as a (Et2O)3LiCl-adduct in the monoclinic space group P21/n with a = 1 111,8(2), b = 1 865,2(6), c = 2 598,3(9) pm, β = 97,41(3)° and Z = 4. The reaction of yttrium tris[bis(trimethylsilyl)amide] with benzonitrile yields the bis(benzonitrile) complex, which crystallizes in the triclinic space group P1 with a = 1 173,7(2), b = 1 210,3(2), c = 1 912,4(3) pm, α = 94,37(1), β = 103,39(1), γ = 117,24(1)° and Z = 2. The amido ligands are in equatorial, the benzonitrile molecules in axial positions. 相似文献
8.
Preparation, Properties and Electronic Raman Spectra of Bis(chloro)-phthalocyaninatoferrate(III), -ruthenate(III) and -osmate(III) Bis(chloro)phthalocyaninatometalates of FeIII, RuIII and OsIII [MCl2Pc(2-)]?, with an electronic low spin ground state are formed by the reaction of [FeClPc(2-)] resp. H[MX2Pc(2?)] (M = Ru, Os; X = Cl, I) with excess chloride in weakly coordinating solvents (DMF, THF) and are isolated as (n-Bu4N) salts. The asym. M? Cl stretch (νas(MCl)) is observed in the f.i.r. at 288 cm?1 (Fe), 295 cm?1 (Ru), 298 cm?1 (Os), νas(MN) at 330 cm?1 (Fe), 327 cm?1 (Ru), and 317 cm?1 (Os); only νs(OsCl) at 311 cm?1 is resonance Raman (r.r.) enhanced with blue excitation. The m.i.r. and FT-Raman spectra are typical for hexacoordinated phthalocyanines of tervalent metal ions. The UV-vis spectra show besides the characteristic π-π* transitions (B, Q, N, L band) of the Pc ligand a number of extra bands at 12–15 kK and 18–24 kK due to trip-doublet and (Pc→M)CT transitions. The effect of metal substitution is discussed. The r.r. spectra obtained by excitation between the B and Q band (λ0 = 476.5 nm) are dominated by the intraconfigurational transition Γ7 Γ 8 arrising from the spin-orbit splitting of the electronic ground state for FeIII at 536 cm?1, for RuIII at 961 cm?1 and OsIII at 3 028 cm?1. Thus the spin-orbit coupling constant increases very greatly down the iron group: FeIII (357 cm?1)< RuIII (641 cm?1)< OsIII (2 019 cm?1). The Γ7 Γ 8-transition is followed by a very pronounced vibrational finestructure being composed in the r.r. spectra by the coupling with νs(MCl), δ(MClN) and the most intense fundamental vibrations of the Pc ligand. In absorption only vibronically induced transitions are observed for the Ru and Os complex at 1 700-2800 rsp. 3100-5800 em?1 instead of the 0-0 phonon transitions. The most intense lines are attributed to combinations of the intense odd vibrational mo-des at ≈ 740 and 1120 cm?1 with ν5(MCI), δ(MClN). 相似文献
9.
Crystal Structure of Bis[lithium-tris(trimethylsilyl)hydrazide] and Reactions with Fluoroboranes, -silanes, and -phospanes Tris(trimethylsilyl)hydrazine reacts with n-butyllithium in n-hexane to give the lithium-derivative 1 . The reaction of 1 with SiF4, PhSiF3, BF3 · OEt2, F2BN(SiMe3)2 and PF3 leads to the substitution products 2–6 . The 1,2-diaza-3-bora-5-silacyclopentane 7 is formed by heating (Me3Si)2N? N(SiMe3)(BFNSiMe3)2 ( 5 ) at 250°C. In the reaction of (Me3Si)2N? N(SiMe3)PF2 ( 6 ) with lithiated tert.-butyl(trimethylsilyl)amine the hydrazino-iminophosphene (Me3Si)2N? N = P? N(SiMe3)(CMe3) ( 8 ) is obtained. In the molar ratio 2:1 1 reacts with SiF4 and BF3 · OEt2 to give bis[tris(trimethylsilyl)hydrazino]silane 9 and -borane 10 . 相似文献
10.
Synthesis and Properties of Diphthalocyaninates of Bismuth, [Bi(Pc)2]k (k = 1?, 0, 1+); Crystal Structure of mixed-valent [Bi(Pc)2] · CH2Cl2 Blue di(phthalocyaninato(2-))bismuthate(III), [Bi(Pc2?)2]?, is obtained by the reaction of BiO(NO3) with molten 1,2-dicyanobenzene in the presence of potassium methylate and isolated as tetra-n-butylammonium (nBu4N)+ and bis(triphenylphosphine)iminium (PNP)+ salt. Green mixed-valent [Bi(Pc)2] · CH2Cl2 is prepared by anodic oxidation of [Bi(Pc2?)2]?. It crystallizes in the orthorhombic γ modification (Pnma; a = 28.176(5), b = 22.913(3), c = 7.925(1) Å, Z = 4). The BiIII ion is eightfold coordinated by the Niso atoms of the slightly distorted Pc ligands in a square antiprismatic manner. The average Bi? Niso bond distance is 2.467 Å. The complex is paramagnetic (μeff = 1.84 μB). Oxidation of [Bi(Pc2?)2]? with bromine yields purple, diamagnetic [Bi(Pc?)2]Brx (1.5 ≤ x ≤ 2.5). The redox properties are investigated electrochemically. UV-Vis-NIR, MIR/FIR and resonance Raman spectra of the new bismuth(III) complexes are discussed and compared with those of diphthalocyaninates of the lanthanides. 相似文献
11.
F. Schaller W. Schwarz H.-D. Hausen K. W. Klinkhammer J. Weidlein 《无机化学与普通化学杂志》1997,623(9):1455-1466
Base-free Tris(trimethylsilyl)methyl Derivatives of Lithium, Aluminium, Gallium, and Indium Base-free LiR* (R*=-C(SiMe3)3) has been prepared from R*Cl and Li-metal in toluene at 85?90°C and used to synthesize the metallanes R*MMe2 with M = Al, Ga and In, respectively. The NMR (1H, 13C, 29Si) and the vibrational spectra of these trisyl compounds have been discussed. AlCl3 and LiR*(ratio 1 : 1) forms the metallate metallate Li[R*AlCl3]. The triclinic unit cell (space group P1 ) consists of a centrosymmetric assoziate, formed by four Li[R*AlCl3]- units with Al? Cl…?Li bridges, two pairs of Li-atoms differing in their chlorine-coordination and two disordered toluene molecules, inserted in the crystal lattice (R1wR2 =0,0444/0,1072). The reaction of GaCl3 with LiR* (I :1) gives the unusual sesquichloride (R*Ga(Cl1,33)Me0,67)3 in moderate yield. The X-ray structure determination shows a Ga3Cl3-skeleton with chairconformation and disordered, terminal gallium ligands (R1/wR2= 0,0646/0,2270). 相似文献
12.
Lithiumphthalocyanines: Synthesis, Properties, and Crystal Structure of Bis(triphenylphosphine)iminiumphthalocyaninatolithates with Different Conformations of the Cation Reaction of tri(n-dodecyl)n-butylammoniumphthalocyaninatolithate, (TDBA)[LiPc2?] with bis(triphenylphosphin)iminiumbromide, (PNP)Br in dichloromethane yields (PNP)[LiPc2?]. It crystallizes in the triclinic space group P1 as dichloromethane solvate ( 1 ) and in the monoclinic space group P21/n as hydrate ( 2 ). The crystal structures of ( 1 ) and ( 2 ) are reported. Each salt contains two crystallographically slightly different discrete [LiPc2?]? anions, in which the square-planar coordinated Li+ cation is centered within the planar Pc2? ligand (Dav.(Li? Niso) = 1.945 Å). There are three different conformations for the (PNP) cation: ( 1 ) only contains the bent conformer (dav.(P? N) = 1.575 Å; φ(P? N? P) = 140.8°), while in ( 2 ) an hybrid (dav.(P? N) = 1.562 Å; φ(P? N? P) = 158.1°) and the linear conformer (dav.(P? N) = 1.547 Å; φ(P? N? P) = 176.8°) are present. The very soluble, blue-green salts melt at 265°C without decomposition. In accordance with cyclovoltammetric data thin films of (PNP)[LiPc2?] are oxidized by NO2 or Br2 to yield brown violet [LiPc?]. The electronic absorption spectra and the vibrational spectra are discussed. 相似文献
13.
Jochen Ellermann Christian Schelle Matthias Moll Falk A. Knoch Walter Bauer 《无机化学与普通化学杂志》1995,621(5):789-798
Chemistry of Polyfunctional Molecules. 116 Hydrido-, Deuterido-, Thiolato-, and Chlororuthenium(II) Complexes of Bis(diphenylphosphino)amine Bis(diphenylphosphino)amine, [(C6H5)2P]2NH (dppa, 1 ), reacts with [Ru(cod)(cot)] (cod = η-1,5-cyclooctadiene, cot = η-1,3,5-cyclooctatriene) ( 2 ) in a molar ratio of 2 : 1 both in a hydrogen or deuterium atmosphere at room temperature to yield cis-[Ru(H)2(dppa)2] ( 3 ) and cis-[Ru(D)2(dppa)2] ( 3 a ), respectively. The dihydride complex 3 is very sensitive towards halogenated solvents: dissolution of 3 in CHCl3 or CH2Cl2 produces the monohydride compound trans-[RuCl(H)(dppa)2] ( 4 ). Treatment of 3 with a threefold excess of tert-butyl mercaptane, Me3CSH, at room temperature results in the formation of cis-[Ru(H)(SCMe3)(dppa)2] ( 5 ). Trans-[RuCl2(dppa)2] ( 7 ) can be synthesized by the interaction of [RuCl2(PPh3)3] ( 6 ) with one or two equivalents of 1 in CH2Cl2 solution. The NMR spectra of 3, 3 a, 4, 5 and 7 are discussed with respect to molecular stereochemistry and hydrogen-halogen exchange under simultaneous cis-trans rearrangement. In addition to 1H, 2H, 31P{1H}, and 31P NMR, the structures of the different complexes were also derived from 1R, Raman, and mass spectra. The NMR spectra simulation of 3 permits detailed assignments of spin-spin coupling constants. Crystals of cis-[Ru(H)(SCMe3)(dppa)2] ( 5 ) are monoclinic, space group P21/c, with a = 1 179.9(3), b = 2 228.0(4), c = 1 854.8(6) pm, β = 96.23(2)°, Z = 4, and Rw = 0.062. The structural analysis shows that ruthenium is coordinated by two bidentate organophosphine ligands and by one tert-butyl thiolate molecule. The metal bound hydrogen atom was not located. However, in agreement with 1H NMR, its position is trans to a phosphorus nucleus. 相似文献
14.
G. Becker B. Eschbach O. Mundt M. Reti E. Niecke K. Issberner M. Nieger V. Thelen H. Nth R. Waldhr M. Schmidt 《无机化学与普通化学杂志》1998,624(3):469-482
Metal Derivatives of Molecular Compounds. IX. Bis(1,2-dimethoxyethane- O,O′ )lithium Phosphanide, Arsanide, and Chloride – Three New Representatives of the Bis(1,2-dimethoxyethane- O,O′ )lithium Bromide Type Experiments to obtain thermally unstable lithium silylphosphanide at –60 °C from a 1,2-dimethoxyethane solution resulted in the isolation of its dismutation product bis(1,2-dimethoxyethane-O,O′)lithium phosphanide ( 1 ). The homologous arsanide 2 precipitated after a frozen solution of arsane in the same solvent had been treated with lithium n-butanide at –78 °C. Unexpectedly, too, the analogous chloride 3 and bromide 4 were formed in reactions of 1-chloro-2,2-bis(trimethylsilyl)-1λ3-phosphaethene with (1,2-dimethoxyethane-O,O′)lithium bis(trimethylsilyl)stibanide and of lithium 1,2,3,4,5-pentaphenyl-2,3-dihydro-1λ3-phosphol-3-ide with ω-bromostyrene, respectively. The monomeric complexes 1 {–100 ± 3 °C; a = 1391.1(4); b = 809.8(2); c = 1249.1(3) pm; β = 102.84(2)°}, 2 {–100 ± 3 °C; a = 1398.3(4); b = 819.8(3); c = 1258.5(4) pm; β = 103.35(2)°} and 3 {–100 ± 3 °C; a = 1308.4(2); b = 788.2(1); c = 1195.6(1) pm; β = 95.35(1)°} crystallize in the monoclinic space group C2/c with four solvated ion pairs in the unit cell; they are isotypic with bis(1,2-dimethoxyethane-O,O′)lithium bromide ( 4 ) {–73 ± 2 °C; a = 1319.0(2); b = 794.1(1); c = 1214.3(2) pm; β = 96.22(1)°}, already studied by Rogers et al. [13] at room temperature. The neutral complexes show a trigonal bipyramidal configuration of symmetry C2, pnicogenanide or halide anions occupying equatorial sites {Li–P 260.4(4); Li–As 269.8(6); Li–Cl 238.6(7); Li–Br 256.3(10) pm} and the chelate ligands spanning equatorial and axial positions {Li–Oeq 205.4(4) to 207.4(4); Li–Oax 208.9(3) to 215.5(2) pm}. The coordination within the (dme)2Li fragment, the Li–X distances (X = P, As, Cl, Br), the structure of the chelate rings, and the packing of the neutral complexes are discussed in detail. 相似文献
15.
On the Preparation of Bis(triphenylsilyl)sulfanes (C6H5)3Si? Sx? Si(C6H5)3 (x = 3, 4) and the Crystal Structure of (C6H5)3Si? S4? Si(C6H5)3 The preparation of the bis(triphenylsilyl)sulfanes Ph3Si? Sx? SiPh3 (x = 3, 4) from Ph3SiSNa and SCl2 resp. S2Cl2 is reported. They are characterized by vibrational, NMR and UV-VIS spectroscopic measurements. Ph3Si? S4? SiPh3 crystallizes in space group P1 with a = 943.6(6) pm, b = 945.7(5) pm, c = 1 881.7(12) pm, α = 82.11(5)°, β = 78.95(5)°, γ = 83.15(5)° and Z = 2. 相似文献
16.
Oxo- and Thiotantalum(V) Compounds: Synthesis of TaOX3 and TaSX3 (X = OR, SR) TaO(OR)3 [R = tC4H9, Mes* ( 2 )], TaO(SR)3 [R = tC4H9, p-Tolyl], TaS(OR)3 [R = tC4H9, Mes* ( 6 )] and TaS(SR)3 [R = tC4H9, p-Tolyl] have been prepared by reaction of TaOCl3 and TaSCl3 with LiOR or LiSR. The reaction of TaCl5 with an excess of LiOMes* yields the chlorotantalum(V)compounds TaCl3(OMes*)2 and TaCl2(OMes*)3 ( 10 ). The synthesis of TaCl2(nC4H9)(OMes*)2 ( 11 ), Ta(Sp-Tolyl)5 and TaCl2(OEt)3 · C5H5N are also described. 2, 6, 10 and 11 decompose in benzolic solution or by heating under vacuum splitting off 2,4,6-tri-tert-butyl-phenol, n-butane respectively, and forming cyclometallated tantalum(V) complexes with the bidentate ligand OC6H2tBu2CMe2CH2. TaCl2(OEt)3 was investigated by X-ray diffraction analysis; the crystal structure has been found to be a binuclear tantalum complex with two bridging ethoxo ligands. 相似文献
17.
Synthesis and Structure of the Platinum(0) Compounds [(dipb)Pt]2(COD) and (dipb)3Pt2 and of the Cluster Hg6[Pt(dipb)]4 (dipb = (i-Pr)2P(CH2)4P(i-Pr)2) The reduction of (dipb)PtCl2 with Na/Hg yields (dipb)Pt as an intermediate which reacts with the amalgam to form the cluster Hg6[Pt(dipb)]4 ( 3 ) or decomposes to (dipb)3Pt2 ( 2 ) and Pt. In the presence of COD [(dipb)Pt]2(COD) ( 1 ) is obtained. 1 crystallizes monoclinicly in the space group P21/c with a = 1596.1(4), b = 996.5(2), c = 1550.4(3) pm, β = 113.65(2)°, Z = 2. In the dinuclear complex two (dipb)Pt units are bridged by a 1,2-η2-5,6-η2 bonded COD ligand. Whereby the C = C double bonds are lengthened to 145 pm. 2 forms triclinic crystals with the space group P1 and a = 1002.0(2), b = 1635.9(3), c = 868.2(2) pm, α = 94.70(2)°, β = 94.45(2)°, σ = 87.95(1)°, Z = 1. In 2 two (dipb)Pt moieties are connected by a μ-dipb ligand in a centrosymmetrical arrangement. 3 is monoclinic with the space group C2/c and a = 1273.8(3), b = 4869.2(6), c = 1660.2(3) pm, β = 95.16(2)°, Z = 4. The clusters Hg6[Pt(dipb)]4 have the symmetry C2. Central unit is a Hg6 octahedron of which four faces are occupied by Pt(dipb) groups. The bonding in the cluster is discussed on the basis of eight Pt? Hg two center bonds of 267.6 pm and two Pt? Hg? Pt three center bonds with Pt? Hg = 288.0 pm. 相似文献
18.
InIII-Phthalocyanines: Synthesis, Properties, and Crystal Structure of Tetra(n-butyl)ammonium-cis-di(nitrito-O,O')phthalocyaninato(2–)indate(III) [In(Cl)Pc2?] reacts with (nBu4N)NO2 in acetone yielding green-blue (nBu4N)cis[In(NO2)2Pc2?], which crystallizes in the monoclinic space group P21/n (No. 14). Both nitrite anions are coordinated as chelating nitrito-O,O'(NO2) ligands to InIII in cis-geometry. Consequently InIII is octa-coordinated within a distorted “quadratic” antiprism and directed towards the Pc2?-ligand. One of the NO2 ligands has equivalent N? O bonds similar to free nitrite, while the other has asymmetric N? O bonds. Both (In,O,N,O) rings are approximately planar with a dihedral angle of 80°. The Pc2? ligand is distorted in an asymmetrically convex manner. Partially overlapping pairs of Pc2? ligands related by an inversion center form double layers, which are separated by layers containing the (nBu4N)+ cations. The cyclic voltammogram shows three electrode processes, which are assigned to the redox pairs: Pc3?/Pc2? (?0.94 V) < InI/InIII (-0.78 V) < Pc2?/Pc? (0.64 V). The UV-VIS-NIR spectra and vibrational spectra are discussed. 相似文献
19.
Heiko Kalpen Wolfgang Hnle Mehmet Somer Ulrich Schwarz Karl Peters Hans Georg von Schnering Roger Blachnik 《无机化学与普通化学杂志》1998,624(7):1137-1147
Bismuth(II) Chalcogenometallates(III) Bi2M4X8, Compounds with Bi24+ Dumbbells (M = Al, Ga and X = S, Se) The ternary bismuth(II) chalcogenometallates(III) Bi2M4X8 (with M = Al, Ga and X = S, Se) were synthesized from the binary chalcogenides M2X3 and Bi2X3 and elementary bismuth. All compounds are diamagnetic semiconductors with Eg (opt.) = 1.8–2.7 eV. The phases (except Bi2Al4Se8) are thermodynamically stable and decompose peritectically above 965–1020 K. Bi2Al4Se8 is metastable below 825 K and is obtained only by rapid quenching from T > 825 K. The isotypic compounds crystallize in a new tetragonal tP28 structure type (P4/nnc). The characteristic unit is the hitherto unknown clustercation Bi24+, with the mean bond length d(Bi–Bi) = 314.2 pm, the Raman frequency 102 cm–1 ≤ νs ≤ 108 cm–1, and the mean force constant of f = 0.68 N · cm–1. The Electron Localization Function, ELF, shows the covalent Bi–Bi bond, the lone electron pairs of the ψ-octahedrally coordinated Bi(II) cations, and the polar character of the Bi–X bonds. 相似文献
20.
Synthesis of Trimethylsilyl Substituted Polyhedra of Calcium, Tin(II), and Phosphorus The reaction of calcium-bis[bis(trimethylsilyl)amide] with bis(trimethylsilyl)phosphane in thf yields the heteroleptic, dimeric (tetrahydrofuran-O)calcium-bis(trimethylsilyl)amidebis(trimethylsilyl)phosphanide 1 (triclinic, P 1 , a = 1066,6(2), b = 1141,3(2), c = 1226,6(2)pm, α = 97,78(3)°, β = 107,47(3)°, γ = 101,12(3)°, Z = 1 dimer). The bridging phosphanide-substituent displays with Ca? P bond lengths of 292,6 and 300,5 pm a distortion of the four-membered Ca2P2-cycle. The reaction with another equivalent of HP(SiMe3)2 in thf leads to the formation of tetrakis(tetrahydrofuran-O)calcium-bis[bis(trimethylsilyl)phosphanide] 2 mit Ca? P distances of 292 pm (monoclinic, P21/c, a = 1626,0(3), b = 1295,3(4), c = 2039,5(5) pm, β = 102,60(2)°, Z = 4). The performance of the reaction in the presence of bis[bis(trimethylsilyl)amino]stannylene yields heterobimetallic compounds with a central polyhedron of Ca-, Sn- and P-atoms. Dependent on the Sn/Ca ratio the isolation of tris(trimethylsilyl)phosphane as well as bis[tris(tetrahydrofuran-O)calcium]-ditin(II)-tetrakis(μ3-trimethylsilylphosphandiide) 3 with a central dicalcia-distanna-tetraphosphacubane-fragment or (thf)2CaSn2[μ-P(SiMe3)2]2[μ3-PSiMe3]2 4 (orthorhombic, Pnma, a = 2247,7(2), b = 1868,9(1), c = 1168,0(1) pm, Z = 4), respectively, succeeds. The Ca? P distances lie at 291 pm. 相似文献