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1.
The reaction of W6Br12 with AgBr in evacuated silica tubes (temperature gradient 925 K/915 K) yielded brownish black octahedra of Ag[W6Br14] ( I ) and yellowish green platelets of Ag2[W6Br14] ( II ) both in the low temperature zone. ( I ) crystallizes cubically (Pn3 (no. 201); a = 13.355 Å, Z = 4) and ( II ) monoclinically (P21/c (no. 14); a = 9.384 Å, b = 15.383 Å, c = 9.522 Å, β = 117.34°, Z = 2). Both crystal structures contain isolated cluster anions, namely [(W6Bri8)Bra6]1– and [(W6Bri8)Bra6])]2–, respectively, with the mean distances and angles: ( I ) d(W–W) = 2.648 Å, d(W–Bri) = 2.617 Å, d(W–Bra) = 2.575 Å, d(Bri…Bri) = 3.700 Å, d(Bri…Bra) = 3.692 Å, ∠W–Bri–W = 60.78°. ( II ) d(W–W) = 2.633 Å, d(W–Bri) = 2.624 Å, d(W–Bra) = 2.613 Å, d(Bri…Bri) = 3.710 Å, d(Bri…Bra) = 3.707 Å, ∠W–Bri–W = 60.23°. The Ag+ cations are trigonal antiprismatically coordinated in ( I ) with d(Ag–Br) = 2.855 Å, but distorted trigonally planar in ( II ) with d(Ag–Br) = 2.588–2.672 Å. The structural details of hitherto known compounds with [W6Br14] anions will be discussed.  相似文献   

2.
The reaction of W6Br12 with CuBr sealed in an evacuated silica tube at the temperature gradient 925/915 K and annealing at 625/300 K yields a mixture of orthorhombic α-Cu2[W6Br14] and cubic β-Cu2[W6Br14] in the low temperature zone. α-Cu2[W6Br14] crystallizes in the space group Pbca (no. 61), a = 15.126 Å, b = 9.887 Å, c = 15.954 Å, Z = 4, oP88, and β-Cu2[W6Br14] crystallizes in the space group Pn3 (no. 201), a = 13.391 Å, Z = 4, cP88. The crystal structures are built up by [(W6Br)Br]2– cluster anions and Cu+ cations. The cluster anions show only in the peripheral shells small deviation from m3m symmetry (d(W–W) = 2.630 Å; d(W–Bri) = 2.618 Å; d(W–Bra) = 2.614 Å). The anions are arranged in a slightly compressed bcc pattern (α) and ccp (β) pattern, respectively. The Cu+ cations are trigonal-planar coordinated by Bra ligands with d(Cu–Br) = 2.377 Å (α) and 2.378 Å (β). The cubic β-modification is diamagnetic with an unexpected large susceptibility (χmol = –884 × 10–6 cm3 mol–1) and have a band gap of 2.8 eV. It decomposes under dynamic vacuum in two steps at 795 K und 1040 K.  相似文献   

3.
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   

4.
The reaction of W6Br12, NaBr, and WO2Br2 in the presence of Br2 in a sealed silica tube yields Na[W2O2Br6] together with WOBr4 and WO2Br2 in the low temperature zone (temperature gradient 1030/870 K). Na[W2O2Br6] crystallizes orthorhombically in the space group Immm (no. 71) with a = 3.775 Å, b = 10.400 Å, c = 13.005 Å and Z = 2. Pairs of condensed trans-[WO2Br4] octahedra with a common Br2 edge form along [100] double chains [W2O4/2Br6]1– via the oxygen atoms. The mixed valent tungsten atoms are bonded to W2 pairs with a 2 c–3 e bond (d(W–W) = 2.946 Å, d(W–O) = 1.888 Å, d(W–Brb) = 2.537 Å, d(W–Brt) = 2.535 Å, ∢O–W–O = 177.4°, ∢Brb–W–Brb (endocyclic) = 109.0°). The Na+ cations connect the anionic double chains to form two-dimensional layers parallel (001), which interact by van der Waals forces. The cations are eightfold coordinated by a cube of the terminal Brt ligands of the polymeric anions (d(Na–Br) = 3.138 Å). Na[W2O2Br6] may be discussed as an intercalation compound of the oxide bromide WOBr3.  相似文献   

5.
Reaction of powdered Zr with ZrCl4, BaCl2 and Be in suitable proportions in a Ta container at 800°C produces the title compound. Suitable monocrystals for X-ray diffraction were obtained from reactions to which a comparable amount of Hg2Cl2 had been added. The structure of Ba3Zr6Cl18Be is a superstructure of the K2ZrCl6 · Zr6Cl18H type (R3 c, Z = 6; a = 9.6852 (9) Å, c = 52.52 (1) Å; R, Rw = 2.7, 3.2% for 826 independent reflections, 2θ ≤ 50°). Trigonally compressed [Zr6(Be)Cl12i]Cl6a clusters are interconnected by six-coordinate barium atoms that lie in Cla antiprisms (a twisted version of the ZrIV site) while (9 + 3)-coordinate barium substitutes for potassium within chlorine layers. Distortions associated with the size and field of barium are responsible for the superstructure and for differences from other analogues.  相似文献   

6.
A cluster complex of the composition [Th(DMSO)8Cl][Re6Se7Cl7] has been obtained by interaction of ThCl4 solution in DMSO with a water solution of K3[Re6Se7Cl7] and KCl. The compound crystallizes in the rhombic space group Pbcm with unit cell parameters a = 12.262(2) Å, b = 19.653(6) Å, c = 23.603(6) Å, V = 5688(2) Å3, Z = 4, d calc = 3.282 g/cm3. The structure is built from centrosymmetric cluster anions [Re6Se7Cl7]3? and complex cations [Th(DMSO)8Cl]3+ possessing mirror-plane symmetry, half of the DMSO ligands being doubly disordered.  相似文献   

7.
利用金属交换法合成了四个新的含钌手性过渡金属簇合物[MRuCo(CO)_8(μ_3-Se)[η_5-C_5H_4C(O)R}]( 1 M= Mo, R= OEt; 2 M= W, R= OEt; 3 M= Mo, R= CH_2CH_2COOMe; 4 M= W, R= CH_2CH_2COOMe),并用红外、核磁、元素分析测试结果进行表征,对簇合物1进行了单晶结构测定,晶体属单斜晶系,P2_1/n空间群,晶胞参数a=10.168(2)A,b=9.018(2)A,c=23.121(3)A,β=92.50(1)°,Z=4。  相似文献   

8.
合成了四个三核簇合物[A]2[MS4(CuCN)2](1A=Et4N,M=Mo;2A=PPh4,M=W;3A=Et4N,M=W;4A=PPh4,M=Mo),测定了[Et4N]2[MoS4(CuCN)2]*H2O(1*H2O)和[PPh4]2[WS4(CuCN)2]*0.5DMF*H2O(2*0.5DMF*H2O)的晶体结构.1和2的簇阴离子[MS4(CuCN)2]2-(M=Mo,W)均具有一个双齿配体MS42-和两个CuCN形成的近似D2d对称性结构.  相似文献   

9.
Reaction of a preformed cluster [{(η5-C5Me5)WS3}3Cu7(MeCN)9](PF6)4 (1) in MeCN with LiCl and PPh3 gave rise to a tetranuclear cationic cluster [(η5-C5Me5)WS3{Cu(PPh3)}3Cl](PF6) (2). The title compound 2 was characterized by elementary analysis, IR, UV-Vis, 1H NMR, and its crystal structure was determined by X-ray single crystal diffraction. It belongs to monoclinic, space group P21/c with a=1.799 8(4) nm, b=2.083 6(4) nm, c=1.913 5(4) nm, β=113.63(3)°, V=6.574(3) nm3, Z=4. The cluster cation [(η5-C5Me5)WS3{Cu(PPh3)}3Cl]+ of 2 contains a strongly distorted, cubane-like structure [WS3Cu3Cl] in which one Cl weakly fills into the void of the nido-like [WS3Cu3] fragment with three relatively long Cu-Cl distances. CCDC: 270415.  相似文献   

10.
Synthesis and Crystal Structure of the Molecular Cluster Compound W6Br14 Brownish-black crystals of W6Br14 are formed in the direct synthesis from W6Br12 and Br2 (400 K). The compound crystallizes cubically with neutral cluster molecules ([W6Br]Br): a = 13.458 Å; Pn3 (Nr. 201); d?(W? W) = 2.653 Å; d?(W? Bri) = 2.616 Å; d?(W? Bra) = 2.569 Å. The W atoms are 0.03 Å outside of the Br cube faces. The molecules are arranged according to a cF point configuration, but each is rotated ?23° about a threefold axis in order to avoid short inter cluster distances Bra? Bra. Nevertheless, via 12 short intermolecular distances per cluster of about d(Bri …? Bra) = 3.487 Å the clusters are interconnected by forming two independent and interpenetrating 3D nets (Cu2O type). Although local distortion of the M6X cluster does not occur, as is expected for this system with 22 electrons per M6 octahedron, it is assumed that the Jahn-Teller theorem is fulfilled collectively via the low-symmetry nets of intermolecular interactions.  相似文献   

11.
12.
New compounds of the general formula A4[Nb6Cl12(NCS)6](H2O)4 (A = K, Rb, NH4) were synthesized from Nb6Cl14 and ASCN in aqueous solutions. X-ray structure refinements were performed on single-crystal data of the three compounds. They are isotypic and crystallize with the space group P1 (Z = 1) and the lattice parameters: a = 877.9(3) pm, b = 1176.6(3) pm, c = 1187.0(3) pm, α = 114.29(1)°, β = 98.96(2)°, γ = 100.91(2)° for K4[Nb6Cl12(NCS)6](H2O)4 ( 1 ); a = 887.6(3) pm, b = 1184.0(4) pm, c = 1195.4(4) pm, α = 114.95(2)°, β = 98.84(2)°, γ = 101.31(2)° for Rb4[Nb6Cl12(NCS)6](H2O)4 ( 2 ) and a = 886.0(4) pm, b = 1181.1(6) pm, c = 1183.9(6) pm, α = 114.49(2)°, β = 99.48(3)°, γ = 101.53(1)° for (NH4)4[Nb6Cl12(NCS)6](H2O)4 ( 3 ). Each centrosymmetric [Nb6Cl12(NCS)6]4? ion of the isotypic compounds contains six terminal thiocyanate groups being bound to the corners of the octahedral niobium cluster through the nitrogen atoms (dNb? N = 221.5(6)–224.3(6) pm, bond angles Nb? N? C 168.6(5)–176.4(6)°). The [Nb6Cl12(NCS)6]4? ions are linked via A? S and A? Cl interactions with the A cations. Half of the cations occur to be disordered along two crystallographic sites.  相似文献   

13.
Synthesis and Crystal Structure of the Tetrameric Nitrido Complex [Cu(CH3CN)4]2[W4N4Cl14(CH3CN)2] . The title compound has been prepared by the reaction of CuCl with WNCl3 in acetonitrile solution, forming red, moisture sensitive crystals. They were characterized by IR spectroscopy and by an X-ray structure determination. Space group I2/a, Z = 4, 2 027 observed unique reflections, R = 0.049. Lattice dimensions at -80°C: a = 2 527.0, b = 971.9, c = 2 137.5 pm, β = 106.01°. The compound consists of [Cu(CH3CN)4]+ ions, which are arranged to form strands, and of anions [W4N4Cl14(CH3CN)2]2?, in which the tungsten atoms were located at the vertices of a square and are linked with one another via linear W?N? W bridges. Two of the four tungsten atoms have four chlorine atoms as terminal ligands, the other two tungsten atoms have three chlorine atoms and an acetonitrile molecule as terminal ligands.  相似文献   

14.
Reactions of (NH4)2MS4, AgBr and CuBr in γ-methylpyridine produced one new compound, [MS4Cu4(γ-MePy)8][M6O19] (1, M = W; 2 , M = Mo), of which 1 was characterized by single crystal X-ray analysis. The crystal data: orthorhombic, Pbcn, a = 15.434(4), b = 16.732(2), c = 28.657(7) Å, V = 7400.8(8) Å3, Z = 4 , R = 0.072 for 3121 independent data. The compound is the first example which contains both polyoxotungstate anion and heteropolynuclear cluster cation. In the structure of the cation four edges of the tetrahedral WS2?4 core are coordinated by four copper atoms, giving a WS4Cu4 aggregate of approximate D2h symmetry. The differences between the reaction of Cu+ with MS2?4 and that of Ag+ with MS2?4 in pyridine and its derivatives are discussed.  相似文献   

15.
1 INTRODUCTION In the last decade, we have been interested in the synthesis of [PPh4][(h5-C5Me5)MS3] (M = Mo, W)[1, 2] , Whose organometallic trisulfido anions show high reactivity towards various transition metals[3~6] . We once reported that the reaction of [PPh4][(h5-C5Me5)WS3] with CuBr in CH3CN afforded a double incomplete-cubane cluster [PPh4]2[(h5-C5Me5)WS3(CuBr)3]2[3], while the analogous reaction of [PPh4][(h5-C5Me5)WS3] with CuBr in CHCl3 gave rise to a 揻our-…  相似文献   

16.
K2W6Br14 ( I ), Rb2W6Br14 ( II ), and Cs2W6Br14 ( III ) were formed by reactions of W6Br12 with the corresponding alkali metal bromides in evacuated silica tubes with a temperature gradient of 925 K/915 K. ( I ) crystallizes in the cubic space group Pn3 (no. 201), a = 13.808 Å, Z = 4, cP88. ( II ) crystallizes in the monoclinic space group C2/c (no. 15), a = 20.301 Å, b = 15.396 Å, c = 9.720 Å, β = 115.69°, Z = 4, mC88. ( III ) crystallizes in the trigonal space group P31c (no. 163), a = 10.180 Å, c = 15.125 Å, Z = 2, hP44. The crystal structures are composed of the isolated [(W6Br)Br]2– cluster anions and the alkali metal cations (d(W–W) = 2.635(2) Å, d(W–Bri) = 2.624(4) Å, d(W–Bra) = 2.595(4) Å). The shape of the anions is influenced by the crystal field symmetry, but the mean bond lengths are not changed by the cation size. The packing of the cluster anions corresponds to ccp pattern in ( I ) and hcp pattern in ( II ) and ( III ), respectively. The alkali metal cations in the octahedral holes are coordinated only by the Bra ligands while those in the tetrahedral and trigonal-bipyramidal cavities are surrounded by Bra and Bri ligands. The details will be discussed and compared with other structures.  相似文献   

17.
Compounds based on new cyanide cluster anions [{Mo6I8}(CN)6]2–, trans-[{Mo6I8}(CN)4(MeO)2]2– and trans-[{W6I8}(CN)2(MeO)4]2− were synthesized using mechanochemical or solvothermal synthesis. The crystal and electronic structures as well as spectroscopic properties of the anions were investigated. It was found that the new compounds exhibit red luminescence upon excitation by UV light in the solid state and solutions, as other cluster complexes based on {Mo6I8}4+ and {W6I8}4+ cores do. The compounds can be recrystallized from aqueous methanol solutions; besides this, it was shown using NMR and UV-Vis spectroscopy that anions did not undergo hydrolysis in the solutions for a long time. These facts indicate that hydrolytic stabilization of {Mo6I8} and {W6I8} cluster cores can be achieved by coordination of cyanide ligands.  相似文献   

18.
V. PERSHINA  B. FRICKE 《ChemInform》1996,27(36):no-no
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

19.
在过去20多年里,人们对合成Mo(W)/Cu/S簇合物一直抱有浓厚的兴趣,这主要缘于此类簇合物丰富的结构化学,以及在生命科学和材料科学方面的潜在应用前景[1,2].在这些簇合物中,含吡啶类配体的Mo(W)/Cu/S簇合物的合成因具有良好的三阶非线性光学性质,近年来受到人们的青睐[3~8].  相似文献   

20.
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