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1.
The preparation of oxovanadium(IV, V) coordination compounds with 2‐acetylpyridine‐2‐furanoylhydrazone (Hapf) is described. [VO(apf)(acac)] was prepared from oxovanadium(IV) diacetylacetonate [VO(acac)2] by reaction with Hapf in methanol or dichloromethane. The complex is paramagnetic and its EPR spectrum is consistent with an octahedral coordination for the vanadium(IV) atom. Voltammetry studies of [VO(apf)(acac)] indicate an irreversible oxidation, in agreement with the chemical behavior of the compound in solution. The vanadium(IV) complex undergoes slow oxidation in alcoholic solution, losing the acetylacetonate ligand to form [VO2(apf)] and [V2O2(μ‐O)2(apf)2]. The crystal structures of these last compounds were determined by X‐ray diffraction methods. [V2O2(μ‐O)2(apf)2] crystallizes monoclinic [P21/c, Z = 2, a = 817.400(10), b = 1650.90(3), c = 984.70(2) pm, β = 112.7190(10)°]. The crystal structure consists of dimeric units, in which two μ‐oxo ligands subtend asymmetric bridges between the vanadium atoms in a very distorted octahedral coordination. In the crystal of [VO2(apf)], orthorhombic [Pnma, Z = 4, a = 1630.000(10), b = 675.10(4), c = 1136.40(2) pm], the vanadium(V) atom is pentacoordinated.  相似文献   

2.
The first crystal structure of a molybdenum complex 9 with a hydrogenated pterin and a sulfur ligand contributes to the discussion about the active center of molybdenum and tungsten enzymes containing a molybdopterin cofactor. Complex 9 was synthesized through a redox reaction of [MoVIO2 (LN-S2)] ( 8 ; LN-S2 = pyridine-2, 6-bis(methanethiolato)) with 5, 6, 7, 8-tetrahydropterin ( 7 ). 2 HCl (H4Ptr.2 HCl). The complex crystallizes, with a non-coordinating Cl-atom acting as a counterion, in the monoclinic space group C2/c (No. 15) with cell dimensions a = 22.900(5), b = 10.716(2), c = 17.551(4) Å, β = 120.36(3)°, and Z = 8. We interpret 9 as [MoIVO(LN-S2)(H+-q-H2Ptr)]Cl (q = quinonoid; H2Ptr = dihydropterin), i.e., a MoIV monooxo center coordinated by a pyridine-2, 6-bis(methanethiolato) ligand and a protonated dihydropterin. The spectroscopic properties of this new complex are comparable to those of other crystalline molybdenum complexes of hydrogenated pterins without additional S-coordination. The slightly H2O-soluble complex 9 reacts with the natural enzyme substrate DMSO very slowly, possibly due to the lack of easily dissociable ligands at the metal center.  相似文献   

3.
Synthesis and Structure of a Binuclear Gadolinium(III) Complex: Magnetic Exchange Interactions in Alkoxy Bridged Lanthanide Complexes The Schiff Base ligand N-salicylidene-2-(bis-(2-hydroxyethyl)amino)ethylamine (H3sabhea) reacts with Gd(NO3)3 · 6 H2O in methanol solution to yield the alkoxy bridged binuclear gadolinium(III) complex [{Gd(Hsabhea)(NO3)}2] · 2MeOH ( 1 ). 1 crystallizes in the monoclinic space group P21/c with a = 1014.8(2), b = 2059.2(4), c = 867.5(2) pm, β = 106.72(2)°, and Z = 2. The two gadolinium atoms are bridged by two alkoxide oxygen atoms with angles of 107.60(11)° at the oxygen bridgeheads and a Gd? Gd separation of 376.43(7) pm. A variable-temperature magnetic susceptibility study (2 to 280 K) of 1 revealed an antiferromagnetic coupling between the Gd(III) ions with J = ?0.198 cm?1 (g = 1.975).  相似文献   

4.
Synthesis, Properties, and Crystal Structure of Cl3(bpy)Ta≡NOCH3, a Methoxynitrene Complex of Tantalum TaCl5 reacts in the presence of 2,2′-bipyridine with O-methyl-hydroxylamine or bis(trimethylsilyl)-O-methyl-hydroxylamine to yield the methoxynitrene complex Cl3(bpy)Ta≡NOCH3. The red complex decomposes only slowly at moist air. It crystallizes in the monoclinic space group C2/c with the lattice constants a = 1588.5, b = 1515.9, c = 1414.2 pm, β = 122.78°, Z = 8. The monomeric complex exhibits a distorted octahedral coordination for the tantalum atom. The methoxynitrene ligand is coordinated by a Ta? N triple bond resulting in a linear Ta≡N? O arrangement with Ta? N? O = 174.0° and distances Ta? N = 174.4 pm and N? O = 134.8 pm. v(Ta? N) is observed in the i.r. spectrum at 950 cm?1.  相似文献   

5.
Treatment of the ligand 6‐aza‐2‐thiothymine (ATT, HL, 1 ) with palladium chloride in methanol forms the ionic complex [(HL)4Pd]Cl2·8MeOH ( 2 ), while its reaction with palladium iodide in same solvent produces the neutral complex trans‐[(HL)2PdI2]·2MeOH ( 3 ) in high yields. The reaction of 1 with Na2[PdCl4] in the presence of sodium acetate in a molar ratio of 2:1:2 and with platinum(II) chloride in presence of sodium acetate led to the dimer tetranuclear complexes [(L4Pd2)NaCl]2·8MeOH ( 4 ) and [L4Pt2Cl2]·6MeOH·H2O ( 5 ). The latter is the first PtIII complex of the ligand. All complexes were characterized by elemental analyses and IR spectroscopy and the crystal structures of 2 , 3 , 4 and 5 are determined by single‐crystal X‐ray diffraction. Crystal data for 2 at ?80 °C: triclinic space group , a = 1006.6(1), b = 1006.9(1), c = 1158.1(1) pm, α = 85.20(1)°, β = 83.84(1)°, γ = 88.91(1)°, Z = 1, R1 = 0.0278; for 3 at ?80 °C: triclinic space group , a = 490.5(1), b = 977.2(2), c = 1116.8(2) pm, α = 90.26(1)°, β = 102.33(1)°, γ = 96.08(1)°, Z = 1, R1 = 0.0394; for 4 at ?80 °C: orthorhombic space group Ccca, a = 1791.7(2), b = 1874.1(2), c = 2044.0(1) pm, Z = 4, R1 = 0.0341 and for 5 at ?80 °C: monoclinic space group P21/c, a = 1464.3(1), b = 2003.7(1), c = 1368.5(1) pm, β = 95.66(1)°, Z = 4, R1 = 0.0429.  相似文献   

6.
Synthesis of Phenylnitrene Complexes with N-Trimethylsilylaniline. II. Characterization and Crystal Structure of the Rhenium(V) Complexes mer-[Re(NPh)Cl3(NH2Ph)(Ph3P)] and trans-[Re(NPh)(OMe)Cl2(Ph3P)2] Reaction of [ReOCl3(Ph3P)2] with N-trimethylsilylaniline yields mer-[Re(NPh)Cl3(Ph3P)2], which reacts under air with excess of N-trimethylsilylaniline to form [Re(NPh)Cl3 · (NH2Ph)(Ph3P)]. Crystallization from CH2Cl2/MeOH affords [Re(NPh)(OMe)Cl2(Ph3P)2] as an additional product. [Re(NPh)Cl3(NH2Ph)(Ph3P)] crystallizes in the monoclinic space group P21/n with a = 1 192.3(3); b = 1 918.9(3); c = 1 266.3(3) pm; β = 101.71(1)°; Z = 4. The rhenium atom has a distorted octahedral environment with the Cl atoms in meridional positions. The phenyl nitrene ligand is coordinated with an almost linear arrangement Re? N1? C40 = 166.8(6)° and with a bond distance Re?N = 170.5(6) pm. [Re(NPh)(OMe)Cl2(Ph3P)2] · 1/2CH2Cl2 crystallizes in the triclinic space group P1 : a = 1 103.1(4); b = 1 227.9(4); c = 1 711.3(5) pm; α = 70.48(3)°; β = 72.71(3)°; γ = 80.03(3)°; Z = 2. The rhenium atom exhibits a distorted octahedral coordination with the Cl atoms and the phosphine ligands in trans positions. As a consequence of the competition of the nitrene ligand and the trans-coordinated methoxy group the Re?;N bond length is slightly lengthened to 173.2(7) pm, while the Re? O bond length of 193.4(6) pm is short. The bond angles Re? N? C70 and Re? O? C80 are 173.3(7)° and 139.1(7)°, respectively.  相似文献   

7.
Silanediyldiphosphinite tBu2Si(OPPh2)2 1 has been synthesised. 1 reacts with the norbornadiene complexes C7H8M(CO)4 (M = Cr, Mo, W) to give six-membered chelate rings of the type cis-M(CO)4[tBu2Si(OPPh2)2] 2–4 . The crystal structures of the chromium and molybdenum complexes cis-Cr(CO)4[tBu2Si(OPPh2)2] 2 and cis-Mo(CO)4[tBu2Si(OPPh2)2] 3 have been determined. Both complexes crystallise in the triclinic system (space group P1 ) with unit cell parameters: ( 2 ) a = 1 093(3) pm, b = 1 477(5) pm and c = 1 542(5) pm; α = 108.4(2)°, b? = 103.87(11)° and b? = 104.57(10)°; U = 2.143(12) nm3; Z = 2; ( 3 ) a = 1 097.8(2) pm, b = 1 483.7(2) pm and c = 1 554.3(2) pm; α = 108.10(1)°, b? = 103.956(6)° and γ = 104.213(7)°; U = 2.1899(6) nm3; Z = 2. Both 2 and 3 consist of discrete, slightly distorted, octahedral monomers in which the six-membered chelate rings are essentially planar. In contrast, the conformations of the chelate rings found in crystal structures of analogous complexes vary from twist-boat to “chaise longue”.  相似文献   

8.
Investigations into Tin(IV) Alkoxides. I. Crystal and Molecular Structure of Tin(IV)-isopropoxide-Isopropanol Solvate, Sn(OiPr)4 · i-PrOH The isopropanol complex of tin(IV)-isopropoxide has been prepared by the reaction of tin tetrachloride with sodium isopropoxide. The compound forms colourless, moisture sensitive crystals, which in dry air easily release the coordinated solvent molecules. The crystal and molecular structure of Sn(OiPr)4 · i-PrOH has been determinated by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/c with a = 1174.2(5), b = 1428.5(3), c = 1234.1(3) pm, β = 95.37(1)° and Z = 4. The crystal structure consists of discrete, dimeric molecules in which the two tin atoms are bridged by two alkoxide groups. The octahedral coordination sphere of each tin atom is completed by one solvent molecule which, in addition, forms one hydrogen bridge to an alkoxide group of the neighboring tin atom.  相似文献   

9.
Preparation and Structure of (2‐Methylpyridinium)3[TbCl6] and (2‐Methylpyridinium)2[TbCl5(1‐Butanol)] The complex chlorides (2‐Methylpyridinium)3[TbCl6] (1) and (2‐Methylpyridinium)2[TbCl5(1‐Butanol)] (2) have been prepared for the first time. The crystal structures have been determinated from single crystal X‐ray diffraction data. 1 crystallizes in the monoclinic space group C2/c (Z = 8) with a = 3241,2(5) pm, b = 897,41(9) pm, c = 1774,2(2) pm and β = 97,83(2)°, 2 in the monoclinic space group P21/n (Z = 4) with a = 1372,96(16) pm, b = 997,57(9) pm, c = 1820,5(2) pm and β = 108,75(1)°. The structures contain isolated octahedral building units [TbCl6]3– and [TbCl5(1‐Butanol)]2–, respectively.  相似文献   

10.
Inhaltsübersicht. PPh4{MoNCl3[N(SiMe3)2]} entsteht aus PPh4[MoNCl4] und N,N,N′-Tris-(trimethylsilyl)benzamidin in siedendem Dichlormethan in Form bernsteinfarbener Kristalle, die wir IR-spektroskopisch und durch eine röntgenographische Strukturanalyse charakterisiert haben. Raumgruppe P21/n, Z = 4, R = 4,3% für 5168 unabhängige beobachtete Reflexe. Die Gitterkonstanten betragen für ?65°C: A = 918,9; b = 2850,5; c = 1353,9 pm; β = 107,51°. Die Verbindung besteht aus PPh4+-Ionen und Anionen [MoNCl3[N(SiMe3)2]}, in denen das Molybdänatom verzerrt tetragonal-pyramidal von dem Nitridoliganden in Apical-Position (r MoN = 165 pm), von drei Chloratomen und von dem N-Atom des Bis(trimethylsilyl)amido-Liganden (r MoN = 194 pm) umgeben ist. Das N-Atom des Amido-Liganden besitzt eine planare Umgebung. PPh4{MoNCl3[N(SiMe3)2]}, a Nitrido Amido Complex of Molybdenum (VI) PPh4{MoNCl3[N(SiMe3)2}] has been prepared by the reaction of PPh4[MoNCl4] with N,N,N′-Tris(trimethylsilyl)benzamidine in boiling dichloromethane, forming amber coloured crystals, which were characterized by their IR spectrum as well as by an X-ray structure determination. Space group P21/n, Z = 4, R = 0.043 for 5168 observed independent reflexions. The lattice dimensions are at ?65°C: A = 918.9; b = 2850.5; c = 1353.9 pm; β = 107.51°. The compound consists of PPh4+ ions and anions {MoNCl3[N(SiMe3)2]} in which the complex molybdenum anion forms a distorted tetragonal pyramid with the nitrido ligand (r MoN 165 pm) in the apical position and the chlorine atoms along with the nitrogen atom of the amido ligand (r MoN 194 pm) in the basical positions. The N atom of the amido ligand has a planar geometry.  相似文献   

11.
12.
Tris[o-mercaptophenolato]vanadium(IV) dimer complexes (A)2[V(mp)3NaLL']2 (A = Ph4P+, H2mp = o-mercaptophenol, L = MeCN, L'=EtOH, (1); L' = MeOH, (2)) were prepared by the reaction of anhydrous VC13, and Na2mp in the molar ratio 1:3. Complex (3) (A = Et4N+, L=L' = MeOH) was prepared by the reaction of VC13, Na2mp and Li2S in the molar ratio 1:2:1. The complexes were characterized by X-ray diffraction crystallography, infrared spectra, magnetic susceptibility, and cyclic voltammetric measurements. Complex 2 crystallizes in the triclinic space group P1 with a=12.813(6), b = 14.199(4), c = 12.790(5) Å, α = 112.72(2), β = 104.24(4). γ = 88.68(4)°, V = 2073.6 Å3, and Z=1. The structure was refined to R=0.058. Complex 3 crystallizes in the mono-clinic space group P21/n with a=12.359(3), b=17.452(6), c=14.829(13) Å, βequals;96.51(5)°, V=3177.8 Å3, and Z=2. The final R factor is 0.067. Both of the anions of 2 and 3 contain two [V(mp)3]2? fragments linked by sodium ions through the μ3-O bridges with a crystallographic center of symmetry. The V(IV) atom is in a coordination environment intermediate between a trigonal prism and an ideal octahedron.  相似文献   

13.
Crystal Structure of the Molybdenum(V) Complex [MoCl3(NtBu)(H2NtBu)]2 · 1/2 C7H8 Green moisture sensitive single crystals of [MoCl3(NtBu)(H2NtBu)]2 ( 1 · 1/2 C7H8) have been prepared from molybdenum pentachloride with Me2Si(HNtBu)2 in toluene solution; they were suitable for a crystal structure determination. 1 · 1/2 C7H8: Space group P 1, Z = 2, lattice dimensions at –83 °C: a = 696.9(1), b = 1470.9(2), c = 1579.0(2) pm, α = 96.673(13)°, β = 92.014(14)°, γ = 94.852(14)°, R = 0.0321. 1 forms centrosymmetric molecules in which the molybdenum atoms are linked by two μ‐Cl‐bridges with MoCl bond lengths of 245.7 and 270.2 pm in average of the two crystallographically independent individuals. The longer MoCl bond is in trans‐position to the nitrogen atom of the imido ligand (MoN distance 169.0 pm, MoNC bond angle 167.0° in average).  相似文献   

14.
[Mo(NPPh3)4]2+ [MoNCl3(NPPh3)]2? · C7H8, a Phosphoraneiminato Complex with a Dication of Molybdenum(VI). The title compound was prepared by the reaction of MoNCl3 with Me3SiNPPh3 in acetonitrile solution. Red single crystals separated upon addition of toluene. They were characterized by IR spectroscopy and by an X-ray structure determination. (Space group P1 , Z = 2, 6918 observed unique reflections, R = 0.059. Lattice dimensions at 20°C: a = 1 181.4, b = 2 021.4, c =2 409.7pm; α = 65.87°, β = 101.09°, γ= 78.97°). In the dication [Mo(NPPh3)4]2+ the molybdenum atom is surrounded in a tetrahedral fashion by the four nitrogen atoms of the phosphorane iminato ligands. The MoN and PN bond lengths correspond well with double bonds. In the two anions [MoNCl3(NPPh3)]?, which occur in different conformations, the molybdenum atoms are fivefold coordinated by the terminal nitride ligand Mo?N: in axial positions and by the three chlorine atoms and the nitrogen atom of the (NPPh3)? ligand in the equatorial positions.  相似文献   

15.
Rb6LiPr11Cl16[SeO3]12: A Chloride‐Derivatized Rubidium Lithium Praseodymium(III) Oxoselenate(IV) Transparent green square platelets with often truncated edges and corners of Rb6LiPr11Cl16[SeO3]12 were obtained by the reaction of elemental praseodymium, praseodymium(III,IV) oxide and selenium dioxide with an eutectic LiCl–RbCl flux at 500 °C in evacuated silica ampoules. A single crystal of the moisture and air insensitive compound was characterized by X‐ray diffraction single‐crystal structure analysis. Rb6LiPr11Cl16[SeO3]12 crystallizes tetragonally in the space group I4/mcm (no. 140; a = 1590.58(6) pm, c = 2478.97(9) pm, c/a = 1.559; Z = 4). The crystal structure is characterized by two types of layers parallel to the (001) plane following the sequence 121′2′1. Cl? anions form cubes around the Rb+ cations (Rb1 and Rb2; CN = 8; d(Rb+?Cl?) = 331 – 366 pm) within the first layer. One quarter of the possible places for Rb+ cations within this CsCl‐type kind of arrangement is not occupied, however the Cl? anions of these vacancies are connected to Pr3+ cations (Pr4) above and below instead, forming square antiprisms of [(Pr4)O4Cl4]9? units (d(Pr4?O) = 247–249 pm; d(Pr4?Cl) = 284–297 pm) that work as links between layer 1 and 2. Central cations of the second layer consist of Li+ and Pr3+. While the Li+ cations are surrounded by eight O2? anions (d(Li?O5) = 251 pm) in the shape of cubes again, the Pr3+ cations are likewisely coordinated by eight O2? anions as square antiprisms (for Pr1, d(Pr1?O2) = 242 pm) and by ten O2? anions (for Pr2 and Pr3), respectively. The latter form tetracapped trigonal antiprisms (Pr2, d(Pr2?O) = 251–253 pm and 4 × 262 pm) or bicapped distorted cubes (Pr3, d(Pr3?O) = 245–259 pm and 2 × 279 pm). The non‐binding electron pairs (“lone pairs”) at the two crystallographically different Ψ1‐tetrahedral [SeO3]2? anions (d(Se4+?O2?) = 169–173 pm) are directing towards the empty cavities between the layer‐connecting [(Pr4)O4Cl4]9? units.  相似文献   

16.
The complexes [Mo(CO)4(L2N,N′)] [L2 = 1‐methylimidazol‐2‐yl(pyridin‐2‐yl)methanone and 1‐benzylimidazol‐2‐yl(1‐phenylaldimine)] have been synthesized from hexacarbonylmolybdenum(0) in order to define the coordination characteristics of the bidentate nitrogen‐donor ligands; the complexes exhibit distorted octahedral coordination for molybdenum(0) and cis‐bidentate ligand configurations.  相似文献   

17.
Sr5[NbN4]N (transparent, red single crystals) was synthesized by reaction of Sr2N with Nb under nitrogen at ambient pressure and 1223 K. The crystal structure was solved and refined in the space group Pbcm (no. 57), Z = 4, with lattice constants a = 646.6(3) pm, b = 1792.5(9) pm, c = 729.8(4) pm, and R = 0.019, wR2 = 0.034. The crystal structure contains both isolated tetrahedra [NbN4]7‐ as well as chains of corner sharing octahedra 1(Sr4Sr2/2N7+). Strontium is irregularly coordinated by nitrogen (CN = 4 ‐ 6, Sr‐N: 252.3(4) ‐ 340.8(3) pm); nitrogen is located in a distorted octahedral environment by strontium and niobium (Nb‐N: 194.5(4) ‐ 199.2(2) pm). By formal reduction of the structural building units to their centers a close structural relationship to both the NiAs and the CaSi type structure is evident.  相似文献   

18.
Syntheses and Crystal Structures of the Rhenium(VII) Nitride Chlorides ReNCl4 and ReNCl4·H2O Rhenium(VII) nitride chloride, ReNCl4 ( 1 ) is obtained in form of brown needles with metallic luster by the reaction of ReCl5 with Cl3VNCl at 140 °C under vacuum in a sealed glass ampoule. It crystallizes in the tetragonal space group I4 with the lattice parameters a = 826.7(4), c = 405.1(2) pm, and Z = 2. The square pyramidal molecules are connected by asymmetric nitrido bridges to form chains along the crystallographic c axis. The shorter Re‐N distance of 163.0(5) pm corresponds to a triple bond, while the pronounced longer distance of 242.0(5) pm can be interpreted with a weak donor bond. The reaction of ReCl5 with VN at 170 °C under vacuum in a sealed glass ampoule yields red needles of ReNCl4·H2O ( 2 ). It crystallizes in the orthorhombic space group Pnma with a = 1075.4(2), b = 1108.5(2), c = 547.7(5) pm and Z = 4. The Re atoms exhibit a distorted octahedral coordination with the aqua ligand in trans position to the nitrido ligand. The Re‐N triple bond has a bond distance of 166.1(11) pm. The complexes are connected by hydrogen bridges O‐H···N to form chains.  相似文献   

19.
Polysulfonylamines. CXVI. Destructive Complexation of the Dimeric Diorganyltin(IV) Hydroxide [Me2Sn(A)(μ‐OH)]2 (HA = Benzene‐1,2‐disulfonimide): Formation and Structures of the Mononuclear Complexes [Me2Sn(A)2(OPPh3)2] and [Me2Sn(phen)2]2⊕ · 2 A · MeCN Destructive complexation of the dimeric hydroxide [Me2Sn(A)(μ‐OH)]2, where A is deprotonated benzene‐1,2‐disulfonimide, with two equivalents of triphenylphosphine oxide or 1,10‐phenanthroline in hot MeCN produced, along with Me2SnO and water, the novel coordination compounds [Me2Sn(A)2(OPPh3)2] ( 3 , triclinic, space group P 1) and [Me2Sn(phen)2]2⊕ · 2 A · MeCN ( 4 , monoclinic, P21/c). In the uncharged all‐trans octahedral complex 3 , the heteroligands are unidentally O‐bonded to the tin atom, which resides on a crystallographic centre of inversion [Sn–O(S) 227.4(2), Sn–O(P) 219.6(2) pm, cis‐angles in the range 87–93°; anionic ligand partially disordered over two equally populated sites for N, two S and non‐coordinating O atoms]. The cation occurring in the crystal of 4 has a severely distorted cis‐octahedral C2N4 coordination geometry around tin and represents the first authenticated example of a dicationic tin(IV) dichelate [R2Sn(L–L′)2]2⊕ to adopt a cis‐structure [C–Sn–C 108.44(11)°]. The five‐membered chelate rings are nearly planar, with similar bite angles of the bidentate ligands, but unsymmetric Sn–N bond lengths, each of the longer bonds being trans to a methyl group [ring 1: N–Sn–N 71.24(7)°, Sn–N 226.81(19) and 237.5(2) pm; ring 2: 71.63(7)°, 228.0(2) and 232.20(19) pm]. In both structures, the bicyclic and effectively CS symmetric A ions have their five‐membered rings distorted into an envelope conformation, with N atoms displaced by 28–43 pm from the corresponding C6S2 mean plane.  相似文献   

20.
During the reaction of Na2[WO4] with YF3 purposed to yield fluoride‐derivatized yttrium oxotungstates(VI), colourless platelet‐shaped single crystals of Na3F[WO4] emerged as main product. The title compound crystallizes orthorhombically in the space group Pnma (a = 559.59(5), b = 751.02(7), c = 1285.98(9) pm) with four formula units per unit cell. Besides isolated ortho‐oxotungstate units [WO4]2? (d(W–O) = 176–178 pm) the crystal structure contains two crystallographically independent Na+ cations which are both octahedrally coordinated by four oxygen atoms and two fluoride anions. The F? anions are surrounded by six sodium cations (d(F–Na) = 224–242 pm) also in an octahedral fashion. These octahedra built up chains along [100] by sharing trans‐oriented faces according to , which are stacked according to a hexagonal closest rod‐packing. The cationic strands are surrounded, interconnected and charge‐balanced by isolated [WO4]2? tetrahedra with almost ideal shape and every O2? ligand is terminally coordinated by three Na+ cations.  相似文献   

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