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1.
The Gadolinium Carbide Halides, Gd4C2X3 (X = Cl, Br) The compounds Gd4C2X3 (X = Cl, Br) and Tb4C2Br3 have been prepared by reaction of the metals (RE), REX3, and C in sealed Ta capsules at 1 100° and 1 300°C, respectively. Monophasic samples of Gd4C2Br3 and Tb4C2Br3 were obtained by reacting stoichiometric mixtures of the starting materials for five days. The needle shaped crystals are bronze-coloured and sensitive to air and moisture. Gd4C2X3 crystallizes in the space group Pnma (No. 62) with lattice constants a = 1 059.6(4), b = 368.4(1), c = 1 962.7(8) pm (Gd4C2Cl3), a = 1 084.4(1), b = 373.0(1), c = 2 036.1(1) pm (Gd4C2Br3). According to Guinier photographs, Tb4C2Br3 is isotypic (a = 1 074.3(2), b = 370.6(1), c = 2 019.4(1) pm). In the crystal structure C is octahedrally coordinated by Gd. The Gd6 octahedra are linked via common edges to form corrugated layers. The X-anions coordinate all free edges and corners of these layers and connect them via Xi? Xi contacts parallel [001]. Gd4C2Br3 shows metallic conductivity. The magnetic susceptibility follows at high temperatures a Curie Weiss law with an effective moment of 7.95 μB. At temperatures below 50 K antiferromagnetic order is observed.  相似文献   

2.
Synthesis and Crystal Structures of Lanthanide Bromide Thiosilicates Ln3Br[SiS4]2 (Ln = La, Ce, Pr, Nd, Sm, Gd) Single crystals of the bromide—thiosilicates Ln3Br[SiS4]2 were prepared by reaction of lanthanide metal (Ln = La, Ce, Pr, Nd, Sm, Gd), sulfur, silicon and bromine in quartz glass tubes. The thiosilicates crystallize in the monoclinic spacegroup C2/c (Z = 4) isotypically to the iodide analogues Ln3I(SiS4)2 and the A—type chloride—oxosilicates Ln3Cl[SiO4]2 with the following lattice constants: La3Br[SiS4]2: a = 1583.3(4) pm, b = 783.0(1) pm, c = 1098.2(3) pm, β = 97.33(3)° Ce3Br[SiS4]2: a = 1570.4(3) pm, b = 776.5(2) pm, c = 1092.2(2) pm, β = 97.28(2)° Pr3Br[SiS4]2: a = 1562.6(3) pm, b = 770.1(2) pm, c = 1088.9(2) pm, β = 97.50(2)° Nd3Br[SiS4]2: a = 1561.4(4) pm, b = 766.0(1) pm, c = 1085.3(2) pm, β = 97.66(3)° Sm3Br[SiS4]2: a = 1555.4(3) pm, b = 758.5(2) pm, c = 1079.9(2) pm, β = 98.28(2)° Gd3Br[SiS4]2: a = 1556.5(3) pm, b = 750.8(1) pm, c = 1074.5(2) pm, β = 99.26(2)° In the crystal structures the bromide ions form chains along [001] with trigonal planar coordination by lanthanide cations, while the [SiS4]4‐—building units display isolated distorted tetrahedra.  相似文献   

3.
Gd10I16(C2)2 and Gd10Br15B2/Tb10Br15B2 Cluster Compounds with M10 Twin Octahedra The compound Gd10I16(C2)2 can be prepared from Gd metal, GdI3 and C at 950 °C. It crystallizes in P1 with a = 10.463(4) Å, b = 16.945(6) Å, c = 11.220(4) Å, α = 99.15(3)°, β = 92.68(3)° und γ = 88.06(3)°. Gd10Br15B2 is formed between 900 und 950 °C, Tb10Br15B2 between 900 und 930 °C from stoichiometric amounts of the rare earth metals, tribromide and boron. Both compounds crystallize in the space group P1 for Gd10Br15B2 with a = 8.984(2) Å, b = 9.816(2) Å, c = 10.552(5) Å, α = 91.14(3)°, β = 114.61(3)° and γ = 110.94(3)° and for Tb10Br15B2 with a = 8.939(4) Å, b = 9.788(3) Å, c = 10.502(2) Å, α = 91.19(3)°, β = 114.51(3)° and γ = 111.10(2)°. In the crystal structures of all three compounds the rare earth metals form edge‐shared Ln10 twin octahedra. In Gd10I16(C2)2 the Gd octahedra are centered with C2 groups (dC–C = 1.43(7) Å). In Ln10Br15B2 (Ln = Gd, Tb) the octahedra contain single boron atoms. The clusters are connected through halide atoms to chains [Ln10(Z)2X X X ]. Adjacent chains are fused threedimensionally via I I for the Gd iodide carbide and via Br Br for the bromide borides of Gd und Tb. It is interesting to see an identical pattern of connection between the chains for the reduced oxomolybdates, e. g. PbMo5O8.  相似文献   

4.
Gd10C4Cl18 and Gd10C4Cl17, Two Lanthanoid Cluster Compounds with Interstitial C2 Units The compounds Gd10C4Cl18 ( I ) and Gd10C4Cl17 ( II ) are prepared by heating stoichiometric amounts of GdCl3, Gd, and graphite in sealed tantalum tubes at 1070 ( I ) and 1 120 K ( II ). Single crystal investigations ( I : P21/c, Z = 2, a = 918.2, b = 1 612.0, c = 1 288.6 pm, β = 119.86°; II : P1 , Z = 1, a = 849.8, b = 917.4, c = 1 146.2 pm, α = 104.56°, β = 95.98°, γ = 111.35°) revealed the occurrence of novel Gd10C4Cl18 clusters. The metal framework is formed by edge-sharing of two Gd6 octahedra. These are centred by C2 units (dC? C = 147 pm) and Cl atoms bridge all available edges of the octahedra. The structure of I corresponds to a packing of such quasi molecular clusters, in II they are linked to chains via common Cl atoms. Both structures are discussed in terms of a model of close packed spheres as well as in the concept of condensed clusters.  相似文献   

5.
The First Gadolinium Carbide Fluoride: Gd2CF2 Gd2CF2, the first gadolinium carbide fluoride is prepared by reaction of stoichiometric amounts of GdF3, Gd, and C at 1250°C in sealed Ta-capsules. It is isotypic with Gd2CBr2 (space group P3 m1; a = 373.11(4) and c = 642.5(1) pm). The Gd atoms surround the C atoms octahedrally. Such Gd6C octahedra are condensed via edges to form octahedral sheets, which are separated by double slabs of F?? ions.  相似文献   

6.
7.
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   

8.
The First Bromide with Trigonal-Bipyramidal [M5(C2)] Clusters: [Pr5(C2)]Br9 The bromide [Pr5(C2)]Br9 is obtained via metallothermic reduction of PrBr3 with rubidium in the presence of praseodymium and carbon in a sealed niobium container at 730°C as dark red single crystals. [Pr5(C2)]Br9 crystallizes in the monoclinic crystal system [P21/n; Z = 4; a = 1 006.9(1); b = 1 886.1(1); c = 1 045.9(1) pm; β = 108.130(1)°; Rint = 0.059; R1 = 0.038; wR2 = 0.077]. One edge in the base of the trigonal bipyramid in [Pr5(C2)]Br9 is usually long (440 pm). It is not brigded by a Bri ligand. In addition to the eight Bri, the cluster is coordinated by 12 terminal ligands (Bra). Except for the known Bra–a–a and Bri–a connections, Bri–a–a brigdes are observed for the first time for trigonal-bipyramidal clusters.  相似文献   

9.
Fluoroplatinates(IV) of the Lanthanides LnF[PtF6] (Ln = Pr, Sm, Gd, Tb, Dy, Ho, Er) For the first time fluorides LnF[PtF6] (Ln = Pr, Sm, Gd, Tb, Dy, Ho, Er), all yellow have been obtained. From single crystal data they crystallize monoclinic, space group P21/n?C (No. 14), Z = 4, Pr: a = 1 125.77(19) pm, b = 559.04(7) pm, c = 910.27(17) pm, β = 107.29(1)°; Sm: a = 1 114.63(31) pm, b = 552.70(12) pm, c = 898.02(20) pm, β = 107.24(2)°; Gd: a = 1 112.12(15) pm, b = 551.22(7) pm, c = 891.99(11) pm, β = 107.09(1)°; Tb (Powder data): a = 1 108.88(20) pm, b = 552.71(9) pm, c = 889.56(16) pm, β = 107.30(1)°; Dy: a = 1 100.28(23) pm, b = 547.77(8) pm, c = 882.41(13) pm, β = 107.32(1); Ho: a = 1 099.11(16) pm, b = 546.16(7) pm, c = 879.45(15) pm, β = 107.34(1)°; Er: a = 1 095.10(16) pm, b = 544.82(10) pm, c = 874.85(14) pm, β = 107.37(1)°.  相似文献   

10.
New Complexes of the Lanthanoides with Bidentate Ligands. The Crystal Structures of [(C17H17N2)GdBr2(thf)2] and [(C17H17N2)3Ln] (L = Sm, Gd) Reaction of [(AIP)Li] with GdBr3 leads to a new mononuclear complex [(AIP)GdBr2(thf)2] 1 . In contrast to this with SmI2 the compound [(AIP)3Sm] 2 is build up. Such complexes are also formed with Gd(OR*)3 (R* = OtBu2C6H3) and [(AIP)Li] in a 1:3 ratio, [(AIP)3Gd] 3 . The structures of 1–3 were characterized by X-ray single crystal structure analysis ( 1 : space group Pna21 (No. 33), Z = 4, a = 1 972.7(9) pm, b = 984.7(5) pm, c = 1 425.0(8) pm, α = β = γ = 90°; 2 · 2 THF: space group C2/c (No. 15), Z = 8, a = 3 644.4(9) pm, b = 1 437.5(5) pm, c = 2 334.4(7) pm, β = 1 21.07(6)°; 3 : space group P2(1)/c (No. 14), Z = 4, a = 1 872.9(1) pm, b = 1 064.6(1) pm, c = 2 282.4(2) pm, β = 103.75(8)°).  相似文献   

11.
Cs[Er10(C2)2]I18 and [Er10(C2)2]Br18: Two New Examples for Reduced Halides of the Lanthanides with Isolated [M10(C2)2] Clusters Cs[Er10(C2)2]I18 is obtained from the reaction of ErI3 with caesium and carbon in sealed tantalum containers at 700°C and [Er10(C2)2]Br18 through the metallothermic reduction of ErBr3 with rubidium in the presence of carbon at 750°C in sealed niobium containers. The crystal structures {Cs[Er10(C2)2]I18: triclinic, P1 ; a = 1 105.2(8) pm, b = 1 112.0(7) pm; c = 1 122.9(8) pm; α = 66.91(3)°, β = 87.14(3)°; γ = 60.80(3)°; Z = 1; R = 0.049, Rw = 0.043; [Er10(C2)2]Br18: monoclinic, P21/n, a = 971.8(6) pm, b = 1 623.4(9) pm, c = 1 163.8(6) pm, β = 104.00(6)°; Z = 2; R = 0.077, Rw = 0.057} contain isolated dimeric [Er10(C2)2] clusters. Due to the inclusion of C2 units, the octahedra are elongated in the direction of the pseudo C4 axis. The connecting edges of the two octahedra are exceptionally short (316.7 pm and 314.8 pm respectively). The dimeric units are connected via Xi?a and Xa?i (X = Br, I) bridges according to [Er10(C2)2XX]X. Cs+ is surrounded by a cuboctahedron of iodide ions in Cs[Er10(C2)2]I18.  相似文献   

12.
New Benzyl Complexes of the Lanthanides. Synthesis and Crystal Structures of [(C5Me5)2Y(CH2C6H5)(thf)], [(C5Me5)2Sm(CH2C6H5)2K(thf)2], and [(C5Me5)Gd(CH2C6H5)2(thf)] YBr3 reacts with potassium benzyl and [K(C5Me5)] in THF to give KBr and the monobenzyl compound [(C5Me5)2 · Y(CH2C6H5)(thf)] 1 . The analogous reaction with SmBr3 in THF leads to the polymeric product [(C5Me5)2Sm(CH2C6H5)2 ∞ K(thf)2] 2 , with GdBr3 to [(C5Me5)Gd(CH2C6H5)2(thf)] 3 . The structures of 1–3 were determined by X-ray single crystal structure analysis:
  • Space group P1 , Z = 2, a = 851.2(4) pm, b = 952.7(4) pm, c = 1858.6(8) pm, α = 79.90(4)°, β = 77.35(4)°, γ = 73.30(3)°.
  • Space group P1 , Z = 2, a = 903.3(2) pm, b = 1375.9(3) pm, c = 1801.1(4) pm, α = 100.92(3)°, β = 100.77°, γ = 98.25(3)°.
  • Space group P21/n, Z = 8, a = 1458.2(5) pm, b = 927.8(3) pm, c = 3792.9(15) pm, β = 96.83(3)°.
  相似文献   

13.
Structure and Thermal Behaviour of Gadolinium(III)-sulfate-octahydrate Gd2(SO4)3 · 8 H2O . Gd2(SO4)3 · 8 H2O crystallizes monoclinic with space group C2/c and the lattice constants a = 13.531(7), b = 6.739(2), c = 18.294(7) Å, β = 102.20(8)°. In the structure Gd is coordinated by 4 oxygen atoms of crystal water and 4 oxygens of sulfate giving rise to a distorted square antiprism. During DTA-TG-experiments the title compound first loses crystal water in a two-step mechanism in the temperature range 130–306°C. The resulting Gd2(SO4)3 is amorphous and recrystallization occurs in the range 380–411°C. The so-obtained low-temperature modification β-Gd2(SO4)3, undergoes a monotropic phase transition at about 750°C to the high-temperature form α-Gd2(SO4)3. The powder pattern of this modification was indexed based on monoclinic symmetry with space group C2/c and lattice constants a = 9.097(3), b = 14.345(5), c = 6.234(2) Å, β = 97.75(8)°. The hightemperature modification of gadolinium-sulfate shows decomposition to Gd2O2SO4 at 900°C and, subsequently, decomposition at 1 200°C yields the formation of C-Gd2O3.  相似文献   

14.
Gd12C6I17 — a Compound with Condensed, C2-Containing Gd6I12 Clusters Gd12C6I17 was isolated in black shining crystals from a reaction product of Gd, GdI3 and graphite, heated in sealed tantalum capsules at 1170 K. The compound is monoclinic (C2/c; a = 1929.7(9), b = 1220.1(5), c = 1863.5(5) pm, = 90.37(3)°). The crystal structure is composed of linear units of 3 condensed Gd6I12 clusters (connection via trans-edges of the central Gd6 octahedron), which are further linked via cis edges to form zig-zag chains. The centres of the Gd6 octahedra are occupied by C2 units. The distances dC? C ≈ 145 pm correspond to a filling of the antibonding π* orbitals of the C2 group, which, however, interact with empty d-orbitals of the metal atoms especially in the apices of the octahedra and thus loose their pure carbon character. The short Gd? C distances (dGd? C = 222 and 227 pm, respectively) are explained as due to multiple bonds. The occurrence of C2 units and single C atoms, respectively, in lanthanide carbides and carbide halides is coupled to the electron concentration of the metal or cluster framework.  相似文献   

15.
Phosphanimine and Phosphoraneiminato Complexes of Beryllium. Crystal Structures of [BeCl2(HNPPh3)2], [BeCl(HNPPh3)2(Py)]Cl, and [Be3Cl2(NPPh3)4] Tetraphenylphosphonium hexachlorodiberyllate, (Ph4P)2[Be2Cl6], reacts with lithium phosphoraneiminate, [LiNPPh3]6, in dichloromethane to give the three‐nuclear beryllium phosphoraneiminate [Be3Cl2(NPPh3)4] ( 3 ). As a by‐product the phosphaneimine complex [BeCl2(HNPPh3)2] ( 1 ) can be isolated, which reacts with pyridine to give the ionic complex [BeCl(HNPPh3)2(Py)]Cl ( 2 ). On the other hand, the silylated phosphanimine Me3SiNP(p‐tolyl)3 ( 5 ) does not react with BeCl2 or (Ph4P)2[Be2Cl6] forming the expected phosphoraneiminates. From CH2Cl2 solutions only the amino‐phosphonium salt [(C7H7)3PNH2]Cl ( 4 ) can be obtained. The compounds 1 ‐ 5 are characterized by single X‐ray analyses and by IR spectroscopy. 1 ·C7H8: Space group C2/c, Z = 4, lattice dimensions at 193 K: a = 1408.9(2), b = 1750.9(2), c = 1633.2(2) pm, β = 106.50(1)°; R1 = 0.0385. 1 forms a molecular structure with short Be—N distances of 169.8(3) pm. 2 ·Py: Space group P1¯, Z = 4, lattice dimensions at 193 K: a = 969.5(1), b = 2077.1(2), c = 2266.4(2) pm, α = 72.24(1)°, β = 87.16(1)°, γ = 77.42(2)°, R1 = 0.0776. 2 forms ion pairs in which the NH atoms of the phosphaneimine ligands act as hydrogen bridges with the chloride ion. The HNPPh3 ligand realizes short Be—N bonds of 169.0(6) pm, the Be—N distance of the pyridine molecule is 182.5(6) pm. 3 ·3CH2Cl2: Space group P1¯, Z = 2, lattice dimensions at 193 K: a = 1333.2(2), b = 1370.2(2), c = 2151.8(3) pm, α = 107.14(1)°, β = 91.39(1)°, γ = 105.15(1)°, R1 = 0.0917. The structure of the three‐nuclear molecule 3 corresponds with a Be2+ ion which is tetrahedrally coordinated by the nitrogen atoms of two {ClBe(NPPh3)2} chelates. 4 ·CH2Cl2: Space group P21/c, Z = 4, lattice dimensions at 193 K: a = 1206.6(2), b = 1798.0(2), c = 1096.2(1) pm, β = 97.65(1)°, R1 = 0.0535. 4 forms dimeric units in which the NH2 groups of the [(C7H7)3PNH2]+ cations act as hydrogen bridges with the chloride ions to give centrosymmetric eight‐membered rings. 5 : Space group P21/n, Z = 4, lattice dimensions at 193 K: a = 1074.3(2), b = 2132.2(3), c = 1075.5(2) pm, β = 110.68(1)°, R1 = 0.0664. 5 forms molecules with distances PN of 154.6(3), SiN of 168.8(3) pm, and bond angle SiNP of 134.4(2)°.  相似文献   

16.
The complexes cis‐[SnCl4(H2O)2]·2H2O ( 1 ), [Sn2Cl6(OH)2(H2O)2]·4H2O ( 3 ), and [HL][SnCl5(H2O)]·2.5H2O ( 4 ) were isolated from a CH2Cl2 solution of equimolar amounts of SnCl4 and the ligand L (L=3‐acetyl‐5‐benzyl‐1‐phenyl‐4, 5‐dihydro‐1, 2, 4‐triazine‐6‐one oxime, C18H18N4O2) in the presence of moisture. 1 crystallizes in the monoclinic space group Cc with a = 2402.5(1) pm, b = 672.80(4) pm, c = 1162.93(6) pm, β = 93.787(6)° and Z = 8. 4 was found to crystallize monoclinic in the space group P21, with lattice parameters a = 967.38(5) pm, b = 1101.03(6) pm, c = 1258.11(6) pm, β = 98.826(6)° and Z = 2. The cell data for the reinvestigated structures are: [SnCl4(H2O)2]·3H2O ( 2 ): a = 1227.0(2) pm, b = 994.8(1) pm, c = 864.0(1) pm, β = 103.86(1)°, with space group C2/c and Z = 4; 3 : a = 961.54(16) pm, b = 646.29(7) pm, c = 1248.25(20) pm, β = 92.75(1)°, space group P21/c and Z = 4.  相似文献   

17.
New Results in the Chemistry of Lanthanoide Complexes. The Crystal Structures of [(C11H21N2)2LnBr] (Ln = Sm, Gd) LnBr3 leads with [(iPr2AIP)Li] (AIP = 2-iPropylamino-4-iPropylimino-2-Pentene) to the mononuclear complex [(iPr2AIP)2LnBr] (Ln = Gd 1 , Sm = 2 ). The structures of 1 – 2 were characterized by X-ray single crystal structure analysis.
  • 1: Space group Cc, Z = 4, a = 1283.3(7) pm, b = 1558.6(8) pm, c = 1330.1(7) pm, β = 90.24(4)°
  • 2: Space group Cc, Z = 4, a = 1281.7(2) pm, b = 1562.3(3) pm, c = 1329.8(2) pm, β = 90.09(1)°.
The Ln-Ion is coordinated by a Brom-Atom and the four Nitrogen-Atoms of the chelate ligand.  相似文献   

18.
Two Fluoride Borates of Gadolinium: Gd2F3[BO3] and Gd3F3[BO3]2 By flux‐supported solid‐state reaction of Gd2O3 and GdF3 with B2O3 (flux: CsCl, molar ratio: 1 : 1 : 1 : 6, sealed tantalum capsule, 700 °C, 7 d) the new gadolinium fluoride borate Gd2F3[BO3] (monoclinic, P21/c; a = 1637.2(1), b = 624.78(4), c = 838.04(6) pm, β = 93.341(8)°; Vm = 64.418(6) cm3/mol, Z = 8) was obtained as colourless, prismatic, face‐rich single crystals. The four crystallographically different Gd3+ cations (CN = 9) are all capped square‐antiprismatically surrounded by fluoride and oxide anions, in which the latter represent always components of isolated trigonal planar [BO3]3— anions. The six crystallographically independent F anions all reside in more or less planar coordination of three Gd3+ cations. Thus the constitution of Gd2F3[BO3] can be described as a sequence of alternating layers each of the composition Gd[BO3] and GdF3 parallel (100), respectively. The crystal structures of Gd2F3[BO3] and the shortly published Gd3F3[BO3]2 (monoclinic, C2/c; a = 1253.4(1), b = 623.7(1), c = 836.0(1) pm, β = 97.404(6)°; Vm = 97.571(9) cm3/mol, Z = 4) are compared with each other. Due to the structural analogies between these two gadolinium fluoride borates, a disorder model of the boron atoms frequently found for Gd2F3[BO3] is able to be transferred to Gd3F3[BO3]2 as well.  相似文献   

19.
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   

20.
Disulfido-Bridged Halo Complexes of Molybdenum (V). Crystal Sructures of (PPh3Me)2 [Cl4Mo (μ-S2)2MoCl4]. 2 CH2Cl2 and (PPh4)2[Br4Mo(μ-S2)2MoBr4]. 3CH2Br2 . Mo(S2)Cl3 is prepared by an improved method; the i.r. spectrum is reported. In dichloro methane solution it reacts with (PPh3Me)Cl forming the complex (PPh3Me)2[Cl4Mo(μ-S2)2MoCl4] · 2 CH2Cl2. The bromo complex (PPh4)2[Br4Mo(μ-S2)2MoBr4] · 3 CH2Br2 is obtained by reaction of MoBr4 with S7NH and subsequent treatment of the reaction mixture with PPh4Br in CH2Br2 solution. Both complexes are characterized by i.r. spectra and structural analyses by X-ray methods. (PPh3Me)2[Cl4Mo(μ-S2)2MoCl4] · 2 CH2Cl2 crystallizes monoclinic in the space group P21/c with two formula units per unit cell (5268 observed independent reflexions, R = 4.0%). The lattice dimensions are: a = 1097 pm, b = 1510 pm, c = 1591 pm, β = 104.4°. (PPh4)2[Br4Mo(μ-S2)2MoBr4] · 3 CH2Br2 crystallizes triclinic in the space group P&1macr; with two formula units per unit cell and the lattice constants a = 1328 pm, b = 1573 pm, c = 1719 pm, α = 95.8°, β = 96.3°, γ = 74.1°. Both compounds are of ionical structure with PPh3Me and PPh4 cations, respectively, and anions [X4MO(μ-S2)2MoX4]2? very similar to each other. The molybdenum atoms are bridged by two disulfido ligands and are bonded directly with a bond length of 286 pm. The terminal halogen atoms add up to coordination number nine at the molybdenum.  相似文献   

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