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1.
Three Oxidation Paths of [Ta6Cl12]2+ ([Ta6Br12]2+ and [Nb6Cl12]2+) [Ta6Cl12]2+ is oxidized autocatalytically to [Ta6Cl12]4+ by HNO3. The titration of [Ta6Cl12]2+ with KBrO3 (in HBr-containing solutions) or with Ce4+ or K2Cr2O7 (in HNO3-containing solutions) leads to a clear [Ta6Cl12]3+ step. The further titration leads beside [Ta6Cl12]4+ to the formation of Ta2O5(· xH2O). [Ta6Cl12]2+ behaves with KBrO3(+ HBr) equally, but the formation of [Ta2O5](· xH2O) is only small. [Nb6Cl12]2+ (22°C) titrated with Ce(ClO4)4 in 2n HClO4 gives the first potential step nearby exact ([Nb6Cl12]3+) and at a very slow titration in a second step a precipitation of Nb2O5(· xH2O) occurs, which adsorbed Ce4+ additionally. At ?15°C with Ce(ClO4)4 the first potential step was exactly at [Nb6Cl12]2+→3+, while the second step needs a distinct additional consumption of titer. (Formation of [Nb6Cl12]4+ and beside it [Nb2O5](· xH2O)). From the titration curves and sections of its normal progress in all cases we get the normal potentials 2+/3+ and 3+/4+ with an accuracy of ± 0.01 volt. In alkaline solution the complexes are oxidized with air-oxygen to [M6X12](OH)62?, while the Br-containing complexes suffer hydrolysis afterwards. 相似文献
2.
Cubic [Ta6Br12(H2O)6][CuBr2X2]·10H2O and triclinic [Ta6Br12(H2O)6]X2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O (X = Cl, Br, NO3) cocrystallize in aqueous solutions of [Ta6Br12]2+ in the presence of Cu2+ ions. The crystal structures of [Ta6Br12(H2O)6]Cl2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O ( 1 ) and [Ta6Br12(H2O)6]Br2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O ( 3 )have been solved in the triclinic space group P&1macr; (No. 2). Crystal data: 1 , a = 9.3264(2) Å, b = 9.8272(2) Å, c = 19.0158(4) Å, α = 80.931(1)?, β = 81.772(2)?, γ = 80.691(1)?; 3 , a = 9.3399(2) Å, b = 9.8796(2) Å, c = 19.0494(4) Å; α = 81.037(1)?, β = 81.808(1)?, γ = 80.736(1)?. 1 and 3 consist of two octahedral differently charged cluster entities, [Ta6Br12]2+ in the [Ta6Br12(H2O)6]2+ cation and [Ta6Br12]4+ in trans‐[Ta6Br12(OH)4(H2O)2]. Average bond distances in the [Ta6Br12(H2O)6]2+ cations: 1 , Ta‐Ta, 2.9243 Å; Ta‐Bri , 2.607 Å; Ta‐O, 2.23 Å; 3 , Ta‐Ta, 2.9162 Å; Ta‐Bri , 2.603 Å; Ta‐O, 2.24 Å. Average bond distances in trans‐[Ta6‐Br12(OH)4(H2O)2]: 1 , Ta‐Ta, 3.0133 Å; Ta‐Bri, 2.586 Å; Ta‐O(OH), 2.14 Å; Ta‐O(H2O), 2.258(9) Å; 3 , Ta‐Ta, 3.0113 Å; Ta‐Bri, 2.580 Å; Ta‐O(OH), 2.11 Å; Ta‐O(H2O), 2.23(1) Å. The crystal packing results in short O···O contacts along the c axes. Under the same experimental conditions, [Ta6Cl12]2+ oxidized to [Ta6Cl12]4+ , whereas [Nb6X12]2+ clusters were not affected by the Cu2+ ion. 相似文献
3.
Preparation of trans-[Mo6Cl8]Cl4Br22? Starting from Crystalline [Mo6Cl8]Cl4(H2O)2 and Crystal Structure of [(C6H5)4As]2[Mo6Cl8]Cl4Br2 The synthesis of the title compound is successful if the crystallized [(Mo6Cl8)Cl4(H2O)2] containing the H2O molecules in trans-position reacts with HBr + [(C6H5)4As]Br in ethanol in a heterogeneous reaction. The X-ray structure investigation confirms the existence of discrete trans-Br-substituted cluster anions of composition [(Mo6Cl8)Cl4Br2]2? in the crystal. The reaction in homogeneous solutions proceeds to Br-enriched compounds. [(C6H5)4As]2[(Mo6Cl8)Cl4Br2] crystallizes in the triclinic space group P¯1 with a = 11.071(2), b = 11.418(2), c = 12.813(2) Å, α = 116.10(2), β = 95.27(2) and γ = 94.41(2)° (?133°C). The crystal structure at ?133°C was determined from single crystal X-ray diffraction data (R1 = 0.026). The [(Mo6Cl8)Cl4Br2]2?-anions are not completely ordered but distributed statistically among the three positions which are possible within the limits of the ordered [Mo6Cl8]-cores (ratio 11:5:4). The frameworks of the anions consist of Mo6 cluster units with (slightly distorted) octahedral arrangement of the metal atoms (d(Mo? Mo): 2.600(1) up to 2.614(1) Å), which are coordinated by the halogeno ligands in a square-pyramidal manner. The details of the structure will be discussed and compared with similar [(Mo6X8)Y4] cluster units (X, Y ? Cl, Br). 相似文献
4.
Synthesis and Crystal Structures of (PPh4)2[As2Se4Cl12] and (PPh4)2[As2Se4Br12] The reaction of PPh4Cl and As2Se3 with SOCl2 or with chlorine in dichloromethane affords (PPh4)2[As2Se4Cl12] with good yields. From PPh4Br, As2Se3 and bromine the corresponding bromo compound was obtained. According to the X-ray crystal structure determinations both compounds are isotypic, crystallizing in the space group of P1 . In the anions two Se2X2 molecules are linked with two X? ions forming an Se4X2 ring in chair conformation. Each X?-ion is associated with an additional AsX3 molecule (X = Cl, Br). 相似文献
5.
Ralf Eßmann Guido Kreiner Anke Niemann Dirk Rechenbach Axel Schmieding Thomas Sichla Uwe Zachwieja Herbert Jacobs 《无机化学与普通化学杂志》1996,622(7):1161-1166
The Structures of some Hexaammine Metal(II) Halides of 3 d Metals: [V(NH3)6]I2, [Cr(NH3)6]I2, [Mn(NH3)6]Cl2, [Fe(NH3)6]Cl2, [Fe(NH3)6]Br2, [Co(NH3)6]Br2 and [Ni(NH3)6]Cl2 Crystals of yellow [V(NH3)6]I2 and green [Cr(NH3)6]I2 were obtained by the reaction of VI2 and CrI2 with liquid ammonia at room temperature. Colourless crystals of [Mn(NH3)6]Cl2 were obtained from Mn and NH4Cl in supercritical ammonia. Colourless transparent crystals of [Fe(NH3)6]Cl2 and [Fe(NH3)6]Br2 were obtained by the reaction of FeCl2 and FeBr2 with supercritical ammonia at 400°C. Under the same conditions orange crystals of [Co(NH3)6]Br2 were obtained from [Co2(NH2)3(NH3)6]Br3. Purple crystals of [Ni(NH3)6]Cl2 were obtained by the reaction of NiCl2 · 6H2O and NH4Cl with aqueous NH3 solution. The structures of the isotypic compounds (Fm3 m, Z = 4) were determined from single crystal diffractometer data (see “Inhaltsübersicht”). All compounds crystallize in the K2[PtCl6] structure type. In these compounds the metal ions have high-spin configuration. The orientation of the dynamically disordered hydrogen atoms of the ammonia ligands is discussed. 相似文献
6.
Bernhard Spreckelmeyer Claus Brendel Mechthild Dartmann Harald Schfer 《无机化学与普通化学杂志》1971,386(1):15-26
When the pyridinium salts (PyH)2[Me6Br]Cl (Me = Nb, Ta) are heated up to about 200°C an exothermic and irreversible transformation occurs. Thereby 6 Cla and 6 Bri exchange their positions. The observations can be interpreted in a way that the halogen sphere – in total or in part – is turned by an angle of 60° in respect to the Me6 octahedron. 相似文献
7.
Alkoxo Compounds of Iron(III): Syntheses and Characterization of [Fe2(OtBu)6], [Fe2Cl2(OtBu)4], [Fe2Cl4(OtBu)2] and [N(nBu)4]2[Fe6OCl6(OMe)12] The reaction of iron(III)chloride in diethylether with sodium tert‐butylat yielded the homoleptic dimeric tert‐‐butoxide Fe2(OtBu)6 ( 1 ). The chloro‐derivatives [Fe2Cl2(OtBu)4] ( 2 ), and [Fe2Cl4(OtBu)2] ( 3 ) could be synthesized by ligand exchange between 1 and iron(III)chloride. Each of the molecules 1 , 2 , and 3 consists of two edge‐sharing tetrahedrons, with two tert‐butoxo‐groups as μ2‐bridging ligands. For the synthesis of the alkoxides 1 , 2 , and 3 diethylether plays an important role. In the first step the dietherate of iron(III)chloride FeCl3(OEt2)2 ( 4 ) is formed. The reaction of iron(III)chloride with tetrabutylammonium methoxide in methanol results in the formation of a tetrabutylammonium methoxo‐chloro‐oxo‐hexairon cluster [N(nBu)4]2[Fe6OCl6(OMe)12] ( 5 ). Crystal structure data: 1 , triclinic, P1¯, a = 9.882(2) Å, b = 10.523(2) Å, c = 15.972(3) Å, α = 73.986(4)°, β = 88.713(4)°, γ = 87.145(4)°, V = 1594.4(5) Å3, Z = 2, dc = 1.146 gcm—1, R1 = 0.044; 2 , monoclinic, P21/n, a = 11.134(2) Å, b = 10.141(2) Å, c = 12.152(2) Å und β = 114.157(3)°, V = 1251.8(4) Å3, Z = 2, dc = 1.377 gcm—1, R1 = 0.0581; 3 , monoclinic, P21/n, a = 6.527(2) Å, b = 11.744(2) Å, c = 10.623(2), β = 96.644(3)°, V = 808.8(2) Å3, Z = 2, dc = 1.641 gcm—1, R1 = 0.0174; 4 , orthorhombic, Iba2, a = 23.266(5) Å, b = 9.541(2) Å, c = 12.867(3) Å, V = 2856(2) Å3, Z = 8, dc = 1.444 gcm—1, R1 = 0.0208; 5 , trigonal, P31, a = 13.945(2) Å, c = 30.011(6) Å, V = 5054(2) Å3, Z = 6, dc = 1.401 gcm—1; Rc = 0.0494. 相似文献
8.
9.
Halomercurates: Syntheses and Crystal Structures of [Cu(en)2][Hg2Cl6], [Cu(en)2][Hg2Br6], and [Cu(en)2][HgBr4] Crystals of [Cu(en)2][Hg2Cl6] ( 1 ) have been obtained by layering a solution of Hg(NO3)2 and NaCl with a solution of [Cu(en)2]SO4. An analogous procedure, using NaBr instead of NaCl, gave crystals of [Cu(en)2][HgBr4] ( 3 ). Crystals of [Cu(en)2][Hg2Br6] ( 2 ) were obtained by gel crystallization using the same starting materials as for 3 . The complexes show very low solubility. The dinuclear anions of 1 consist of two nearly planar HgCl3 units related by a center of symmetry. In 2 infinite anionic chains are present, made up of parallel HgBr3 units. These units are packed in such a way as to produce a trigonal bipyramidal configuration around the Hg atoms. 3 contains mononuclear deformed tetrahedral [HgBr4]2– anions. In all three complexes the packing of the ions is such that halogen atoms of halomercurate anions complete a tetragonal bipyramidal coordination at Cu. The resulting Cu–Halogen distances are 2.924 Å for 1 , 3.036 Å for 2 and 3.085 and 3.119 Å for 3 . 1 : Space group P 1, Z = 1, lattice constants at 20 °C: a = 7.000(2), b = 7.526(2), c = 8.239(2) Å; α = 88.39(2), β = 86.06(2), γ = 86.10(3)°; R1 = 0.040. 2 : Space group P21/c, Z = 2, lattice constants at –50 °C: a = 7.185(1), b = 16.338(2), c = 7.814(1) Å; β = 94.88(2)°; R1 = 0.033. 3 : Space group P21/n, Z = 4, lattice constants at 20 °C: a = 8.055(3), b = 13.101(3), c = 13.814(3) Å; β = 91.24(3)°; R1 = 0.092. 相似文献
10.
D"yachenko O. A. Bardin A. A. Kotov A. I. Shilov G. V. Gritsenko V. V. Buravov L. I. Mizuno M. 《Russian Chemical Bulletin》2003,52(2):375-379
The structures of organic metals (DOET)4[Hg2Cl6] (1) and (DOET)4[Hg2Br6] (2), where DOET is (1,4-dioxanediyl-2,3-dithio)ethylenedithiotetrathiafulvalene, were established by X-ray diffraction analysis. Compounds 1 and 2 are isostructural, and their crystals have layered structures. The conducting layers formed by the stacked DOET1/2+ cations alternate with the layers of the [Hg2X6]2– anions (X = Cl, Br). The temperature dependence of the conductivity of salt 1 shows a metallic character in the range of 300—4 K. Compound 2 undergoes the metal—semiconductor phase transition (TM—I) at 100 K. 相似文献
11.
Shamshurin M. V. Abramov P. A. Mikhaylov M. A. Sokolov M. N. 《Journal of Structural Chemistry》2022,63(1):81-86
Journal of Structural Chemistry - Extracting the reaction product of Ta, Br2, and LiBr (720 °C, 48 h, mole ratio 1.5:1.75:1.0) with diglyme yields crystals of complex... 相似文献
12.
Phosphoraneiminato Complexes of Boron. Syntheses and Crystal Structures of [BBr2(NPMe3)]2, [B2Br3(NPiPr3)2]Br, [B2(NPEt3)4]Br2, [B2Br2(NPPh3)3]BBr4 and [{B2(NMe2)2}2(NPEt3)2]Cl The bromoderivatives of the title compounds are prepared from the corresponding silylated phosphoraneimines Me3SiNPR3 and boron tribromide. The boron subcompound [{B2(NMe2)2}2(NPEt3)2]Cl2 derives from Me3SiNPEt3 and B2Cl2(NMe2)2. All complexes are characterized by NMR and IR spectroscopy as well as by crystal structure determinations. [BBr2(NPMe3)]2 (1): Space group P21/n, Z = 2, R = 0.031. Lattice dimensions at ?50°C: a = 723.8, b = 894.2, c = 1305.4 pm, β = 92.35°. 1 forms centrosymmetric molecules in which the boron atoms are linked via μ2-N bridges of the NPMe3? groups of from B2N2 four-membered rings with B? N distances of 149.9 and 150.9 pm. B2Br3(NPiPr3)2]Br (2): Space group P21, Z = 2, R = 0.059. Lattice dimensions at ?80°C: a = 817.6, b = 2198.7, c = 851.5 pm, β = 115.09°. In the cations of 2 the boron atoms are lined via the μ2-N atoms of the NPiPr3? groups to form planar, asymmetric B2N2 four-membered rings with B? N distances of 143 and 156 pm. [B2(NPEt3)4[Br2·4CH2Cl2 (3): Space group C2/c, Z = 4, R = 0.042. Lattice dimensions at ?50°C: a = 1946.1, b = 1180.3, c = 2311.3 pm, β = 101.02°. The structure contains centrosymmetric dications in which both the boron atoms are lined by the N atoms of two of the NPEt3? groups to form a B2N2 four-membered ring with B? N distances of 149.6 pm. The remaining two NPEt3? groups are terminally bonded with very short B? N distances of 133.5 pm. B2Br2(NPPh3)3]BBr4 (4): Space group P1 , Z = 2, R = 0.065. Lattice dimension at ?50°C: a = 1025.7, b = 1496.1, c = 1807.0 pm, α = 85.09°, β = 82.90°, γ = 82.72°. In the cation the boron atoms are lined via the μ2-N atoms of two of the NPPh3? groups to form a nearly planer B2N2 four-membered ring with B? N distances of 149.3-153.1 pm. The third NPPh33 group is terminally connected with teh sp2 hybridized boron atom and with a B? N distance of 134.1 pm along with an almost linear BNP bond angle of 173.6°. [{B2(NMe2)2}2(NPEt2)2]Cl2 · 3CH2Cl2 (5): Space group C2/c, Z = 4, R = 0.098. Lattice dimensions at ?70°C: a = 1557.9, b = 1294.7, c = 2122.9 pm, β = 96.08°. The structure of 4 contains centrosymmetric dications in which two by two B-B dumb-bells are linked via the μ2-N atoms of the two NEPt3? groups to form B4N2 six-membered rings with B? N distances of 150 and 156 pm and B-B distances of 173 pm. The B? N distances of the terminally bonded NMe2? groups correspond to 138 pm double bonds. 相似文献
13.
Synthesis, Crystal Structure and Spectroscopic Characterization of [Au12(PPh)2(P2Ph2)2(dppm)4Cl2]Cl2 The reaction of [(AuCl)2dppm] (dppm = Ph2PCH2PPh2) with P(Ph)(SiMe3)2 in CHCl3 results in the formation of [Au12(PPh)2(P2Ph2)2(dppm)4Cl2]Cl2 ( 1 ), the crystal structure of which was determined by single crystal X‐ray analysis (space group P21/c, a = 1425.3(3) pm, b = 2803.7(6) pm, c = 2255.0(5) pm, β = 95.00(3)°, V = 8977(3)·106 pm3, Z = 2). The dication in 1 consists of two Au6P3 units built by highly distorted Au3P and Au2P2 heterotetrahedra, connected via four bidentate phosphine ligands. Additionally, the compound was characterized by IR‐, UV‐ and NMR spectroscopy. The 31P{1H} NMR spectrum is discussed in detail. 相似文献
14.
1INTRODUCTION Molybdenum(II)halide clusters containing[Mo6-X8]4 cores have been the subject of interest for over five decades[1].This octahedral cluster-type comple-xes comprise an important,and in a sense archetypal,class of higher nuclearity transition metal cluster com-plexes.Their high symmetry,photochemical and pho-tophysical properties as well as structural relation-ships to cluster complexes of other elements exhibit significant interest[2].In addition,there is a structural simila… 相似文献
15.
The Adduct of BiCl3 and Mo6Cl12: [BiCl] Dumbbells in the Structure of [BiCl][Mo6Cl14] MoCl3 reacts under decomposition to MoCl2 and Cl2 with BiCl3 in a sealed evacuated glass ampoule at 550 °C to form light red crystals of [BiCl][Mo6Cl14]. The crystal structure determination (monoclinic, C 2/c, a = 1268.1(4) pm, b = 1304.6(3) pm, c = 2571.9(8) pm, β = 91.79(3)°, Z = 8) shows that the structure is built of [(Mo6Cl8)Cl6] units containing nearly regular octahedral Mo6 clusters. These units are arranged in the motiv of a cubic closest packing. The octahedral interstices contain [BiCl] dumbbells with a Bi–Cl bond length of 249 pm. The coordination sphere of the Bi atom is completed by six weaker Bi–Cl-contacts of 275 to 308 pm length to a distorted monocapped trigonal prism. Neglecting the secondary Bi–Cl bonds, the title compound can be formulated as [(BiCl)2+][(Mo6Cl14)2–]. 相似文献
16.
Thermodynamics and Kinetics of the Xa-Substitution of [W6Cl8]X6a(2?) and [Mo6Cl8]X6a(2?) Complexes; (X = Cl, Br, I) The title subject has been investigated in different solvent mixtures (see “Inhaltsübersicht”). In some cases the progress of the reaction has been followed by an emf method; in most cases the reaction was stopped after definite times by precipitation of the oxiniumsalts. Thermodynamics. For equilibria of the type (a) one finds the constant \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm C} = \frac{{[{\rm Br}^{\rm a} ][{\rm Cl}^ - ]}}{{[{\rm Cl}^{\rm a} ][{\rm Br}^ - ]}} $\end{document}, where [Bra] and [Cla] mark the total number of Br or Cl occupying Xa-positions of the complex. The Xa-positions are thermodynamically equivalent, the substitution proceeds statistically, so that the steps of reaction (a) with the equilibrium constants K1 to K6 are given by \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm K} = \frac{{{\rm W}({\rm hin})}}{{{\rm W}({\rm r\ddot uck})}} \cdot {\rm C} $\end{document} if W(hin) and W(rück) describe the probability of the forward and the back reaction. Similarly in some simple complexes (e. g. Irx62?);PdX42? the statistical effect plays a dominating role. The kinetics may be described as (b) The aquotation step is rate determining. Consequently the reaction of the first order. Rate constants for the forward and the reversed reaction between 0 and 25°C have been measured. The activation energy is ≈ 18 kcal. With the molybdenum complexes the Xa-substitutions is about 10 times faster as with the tungsten complexes. 相似文献
17.
18.
Synthesis and Structure of [Fe6(CO)12(TePh)12] The reaction of [Fe(CO)4(HgCl)2] with PhTeSiMe3 leads to the formation of red needles. [Fe6(CO)12(TePh)12] was characterised by single crystal x‐ray structure analysis. In this compound each iron atom is coordinated octahedrally by four μ2‐TePh groups and two terminal CO groups. The iron atoms form a six membered planar ring. 相似文献
19.
Preparation and Vibrational Spectra of Dichloro and Dibromodithiophosphate. Crystal Structures of [PPh3Me][PS2Cl2] and [PPh4][PS2Br2] Dichloro and dibromodithiophosphates [Cat+][PS2X2?] with a large organic cation can be obtained from P4S10, CatX and HX in CH2Cl2 (Cat+ = PPh4+, PPh3Me+; X = Cl, Br). The vibrational spectra (i.r. and Raman) of the [PS2X2]? ions are reported and discussed; force constants were calculated. The crystal structures of [PPh3Me][PS2Cl2] and [PPh4][PS2Br2] were determined and refined with X-ray diffraction data. In both cases, simple anions [PS2X2]? are present. [PPh3Me][PS2Cl2]: orthorhombic, space group P212121, a = 1089, b = 1334, c = 1476 pm, Z = 4, refinement to a residual index R = 0.046 for 1116 reflexions; the structure is isotopic with [PPh3Me][VO2Cl2]. [PPh4][PS2Br2]: tetragonal space group I4 , a = 1301, c = 721 pm, Z = 2, refinement to R = 0.065 for 357 reflexions; the structure is isotypic with [AsPh4][FeCl4] with [PS2Br2]? ions occupying positions of 4 -symmetry with statistical orientation (statistical superposition of Br and S positions). 相似文献
20.
Crystal Structures of [Et3PNAsPh3]2[Ag2Br4] and [Et3PNAsPh3]2[Pd2Br6] Colourless single crystals of [Et3PNAsPh3]2[Ag2Br4]( 1 ) and red single crystals of [Et3PNAsPh3]2[Pd2Br6]( 2 ) have been isolated from saturated solutions in acetonitrile of equivalent mixtures of [Et3PNAsPh3]Br with AgBr and PdBr2, respectively. Both complexes were characterized by IR spectroscopy and by crystal structure determinations. 1 : Space group P1¯, Z = 1, lattice dimensions at ‐70°C: a = 985.0(2), b = 1042.2(5), c = 1345.8(5) pm, α = 102.88(2)°, β = 105.73(2)°, γ = 94.94(2)°, R1 = 0.0577. 2 : Space group P21/c, Z = 2, lattice dimension at ‐70°C: a = 1003.0(1), b = 1371.8(2), c = 1974.0(1) pm, β = 93.30(1)°, R1 = 0.0458. The dimeric anions of 1 and 2 form planar, centrosymmetric complex units. 相似文献