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1.
Black single crystals of LiNb6Cl15 were obtained from reactions of Nb powder, NbCl5 and LiCl in sealed niobium tubes at 850°C. The heavy atom structure of LiNb6Cl15 (Ia3 d (no. 230), Z = 16, a = 2055.5(2) pm at 100 K, R(F) = 0.028, R(F2) = 0.053) is isotypic with the structure of Ta6Cl15. The [Nb6Cl12]2+ clusters in the structure are three-dimensionally interconnected via three additional Cla?a. These bridge all vertices of niobium clusters, consistent with [Nb6Cl12iCl]? (the Nb? Cla–a? Nb angles are 140°). At low temperatures the lithium ions are disordered over one-third of sites (48 f), occupying cavities inside of two distorted corner-sharing tetrahedra of chloride. These positions for lithium represent the narrowest sections of infinite channels in the structure built up by chloride. An increased lithium ion mobility is obtained above 170 K by 7Li-NMR measurements.  相似文献   

2.
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   

3.
NbOCl3 was obtained from a reaction of NbCl5 and Nb2O5 at 260?C. Contrary to the literature data, NbOCl3 crystallizes in the non‐centrosymmetric space group P&4macr;21m as determined by single‐crystal and powder X‐ray diffraction data (crystal: a = b = 1089.59(6) pm, c = 394.79(2) pm, Z = 4, R1 = 0.0229, wR2 = 0.0459, powder: a = b = 1086.36(6) pm, c = 393.65(2) pm). The niobium atoms are surrounded by distorted octahedra built of four chlorine atoms and two oxygen atoms in trans positions. Two such octahedra are edge‐bridged through shared chlorine atoms, forming dimers. These units are linked to each other by apical oxygen atoms forming one‐dimensional Nb2Cl6O2 chains parallel [001]. Contrary to the literature data two different Nb‐O distances are obtained.  相似文献   

4.
Cesium Chromium Halides Cs3CrCl6, Cs3Cr2Cl9, and Cs3CrBr6 – Preparation, Properties, Crystal Structure The crystal structures of Cs3CrCl6 and Cs3Cr2Cl9 were determined and redetermined by X‐ray single‐crystal studies (space group Pnnm, Z = 6, a = 1115.6(2) pm, b = 2291.3(5) pm, c = 743.8(1) pm, Rf = 7.73%, 1025 unique reflections with I > 2σ(I) (Cs3CrCl6); P63/mmc, Z = 2, a = 721.7(2) pm und c = 1791.0(1) pm; Rf = 2.06%, 395 unique reflections with I > 2.5σ(I) (Cs3Cr2Cl9). The structure of Cs3CrCl6 consists of two different isolated CrCl6 octahedra and five crystallographic different Cs+ ions. The CrCl6 octahedra form ropes in the direction [001]. Because of orientational disordering of the Cr(1)Cl6 octahedra and the an only half‐occupation of some cesium and chlorine sites Cs3CrCl6 is strongly disordered in direction of the (020) plane. The ionic conductivity of Cs3CrCl6, which was expected owing to the great disorder, however, is with 7.3 × 10–5 Ω–1 cm–1 at 740 K relatively small. The compound Cs3CrBr6, which was firstly prepared by quenching stoichiometric amounts of CsBr and CrBr3 from 833 K, is metastable at ambient temperature. It is probably isostructural to Cs3CrCl6 as shown by X‐ray powder photographs.  相似文献   

5.
Structure and Electrochemical Study of Nb3Cl8 The compound Nb3Cl8 was synthesized from NbCl5 and niobium metal in a sealed quartz ampoule at 700 °C. Single crystals, obtained from LiCl melt were used for X‐ray structure determination (space group P 3 m1, Z = 2, lattice parameters a = b = 672.95(7) pm, c = 1223.2(2) pm (at 100 K), R1 = 0.029, wR2 = 0.064 for all independent reflections). Electrical resistivity measurements are reported. Electrochemical intercalation of lithium into the structure of Nb3Cl8 was studied.  相似文献   

6.
Synthesis of the Dichloromethyleneiminium Salts Cl2C?NClH+MF6? and Cl2C?NClCH3+ MF6? (M = As, Sb) and Crystal Structure of Dichloromethyleneiminium-hyxachloroantimonate Cl2C?NH2+SbCl6? The N-chloro-dichloromethyleneiminium salts Cl2C=NCIH+MF6? (M = As, Sb) are prepared by protonationof trichloromethyleneimine in the superacide system HF/MF5 at 195 K. The synthesis of the N-chloro-N-methyl-dichloromethyleneiminium salts Cl2C?NClCH3+MF6? (M = As, Sb) is proceeded by methylation of perchloromethylenimine by CH3OSO+MF6? in SO2 also at low temperature. All salts are characterized by vibrational and NMR spectra. The dichloromethyleneiminiumhexachloroantimonate crystallizes in the space group P21/c with a = 971.3(4)pm, b = 1134.0(4)pm, c = 2154.2(7)pm β = 102.04(3)° and Z = 8.  相似文献   

7.
Pr8Cl7B7 is prepared from stoichiometric mixtures of PrCl33, Pr and B at 1220 K in closed Ta capsules. Pr8Cl7B7 forms golden coloured needles sensitive to moist air. It crystallizes in the space group P1 with a = 773.1(2) pm, b = 903.0(2) pm, c = 1419.4(3) pm, a = 81.55(3)°, β = 82.18(3)°, and γ = 64.76(3)°. In the crystal structure Pr6 trigonal prisms are condensed to double chains which run parallel [100]. Some of the prisms and rectangular prism faces are centered by boron atoms which leads to B3, B6, B8 rings, and B2 dumbbells condensed into ribbons. These Pr8B7 strands are surrounded and held together by the Cl atoms. Pr8Cl7B7 is a metallic conductor and shows Curie Weiss behavior with μeff = 3.48 μB. According to extended Hückel calculations, the distribution of valence electrons is best described by a formulation Pr818+Cl77−B711−. Bonding within the boron ribbons is thus nearly optimal, while the average 4f2 5d3/4 configuration of Pr accounts for both the observed magnetic moment and metallic conductivity.  相似文献   

8.
Cs2LiLuCl6 (form II, metastable at room temperature) and Cs2KScCl6 were obtained as single crystals from reaction of CsLu2Cl7: Li = 1:1 and Cs3Sc2Cl9: K = 1:2 in arc-welded tantalum tubes at 500°C. They crystallize with the cubic face-centered K2NaAlF6-type structure (elpasolite, Fm3m, Z = 4) with a = 1040.9 pm, x(Cl) = 0.2483(4) [Cs2LiLuCl6-II] and a = 1087.3(3) pm, x(Cl) = 0.2263(6) [Cs2KScCl6].  相似文献   

9.
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   

10.
Oxidative Addition of N‐chlorotriphenylphosphoraneimine onto Phosphorus(III) Chloride and Antimony(III) Chloride. Crystal Structures of (Cl3PNPPh3)2[PCl6][ClHCl], [SbCl4(HNPPh3)2][SbCl6], and [Sb(NPPh3)4][SbCl6] Phosphorus(III) chloride reacts with N‐chlorotriphenylphosphoraneimine, ClNPPh3, in CH2Cl2 solution strongly exothermically via oxidative addition to give (Cl3PNPPh3)2[PCl6][ClHCl] ( 1 ). As a by‐product, Ph3PNP(O)Cl2 can be obtained, which is formed from PCl3 and ClNPPh3 in the presence of POCl3. In contrast to these results, antimony(III) chloride reacts with ClNPPh3 in CH2Cl2 solution to give a mixture of the phosphoraneimine complex [SbCl4(HNPPh3)2][SbCl6] ( 2 ) and the phosphoraneiminato complex [Sb(NPPh3)4][SbCl6] ( 3 ). The complexes 1 ‐ 3 were characterized by IR spectroscopy and by single crystal X‐ray determinations. 1 : Space group C2/c, Z = 4, lattice dimensions at 193 K: a = 3282.0(2), b = 798.7(1), c = 1926.1(2) pm, β = 107.96(1)°, R1 = 0.0302. 1 contains [Cl3PNPPh3]+ cations with PN bond lengths of 152.5(2) and 160.9(2) pm, and a PNP bond angle of 140.5(1)°. 2 ·CH2Cl2: Space group , Z = 2, lattice dimensions at 193 K: a = 1031.2(1), b = 1448.3(2), c = 1811,4(2) pm, α = 70.96(1)°, β = 87.67(1)°, γ = 75.37(1)°, R1 = 0.0713. 2 ·CH2Cl2 contains cations [SbCl4(HNPPh3)2]+ with octahedrally coordinated Sb atom and the HNPPh3 ligand molecules being in trans‐position. Sb–N bond lengths are 207.6(6) and 209.3(6) pm, PN bond lengths 162.3(7) and 160.8(7), which approximately corresponds with double bonds. 3 ·0.5CH2Cl2: Space group P4/n, Z = 2, lattice dimensions at 193 K: a = b = 1678.8(1), c = 1244.3(1) pm, R1 = 0.0618. 3 ·0.5CH2Cl2 contains [Sb(NPPh3)4]+ cations with tetrahedrally coordinated Sb atom and short Sb–N bond lengths of 193.7(6) pm. The PN distances of the phosphoraneiminato ligands, (NPPh3)? with 156.5(6) pm, correspond with double bonds, the SbNP bond angles are 130.6(3)°.  相似文献   

11.
Thermochemistry and Structure of Beryllium Chloride BeCl2 is dimorphous, with a transition point at 405°C. The transition enthalpy and transition entropy have been determined by solution calorimetry: ΔUH° = 2.9 kJmol?1 and ΔUS° = 9.7 JK?1mol?1. The previously known SiS2-type structure of BeCl2 is that of the high temperature phase. The structure of the phase stable at room temperature has been determined from single crystal data. a = 1 062.4(6) pm, c = 1 804(2) pm, I41/acd, Z = 32, R = 0.038 (Mg(NH2)2-type). The structure consists of P4O10-like [Be4Cl6Cl4/2]-units, connected by their terminal anions.  相似文献   

12.
The tantalum derivative TaCl5(SOCl2), thermally unstable above 290 K, was prepared from Ta2Cl10 and SOCl2 and studied by X‐ray crystallography at 180 K. Tantalum atom is octahedrally coordinated by five chlorides at Ta–Cl distances comprised between 2.32 and 2.36 Å and by the oxygen atom of SOCl2 at the Ta–O distance of 2.34 Å. No evidence for the existence of an analogous compound of niobium(V) has been obtained. The halides of Group 5, M2Cl10, M = Nb, Ta, react with SeOCl2 to give the solid adducts MCl5(SeOCl2) stable at room temperature. The reaction of NbCl5(SeOCl2) with SOCl2 affords [SeCl3][NbCl6] which contains trigonal‐pyramidal (SeCl3)+ cations with Se–Cl distances of 2.13–2.16 Å and octahedral [NbCl6] anions (Nb–Cl: 2.27–2.45 Å). A distorted octahedral coordination around the selenium atom is achieved by additional interactions [Se…Cl, 2.81–2.98 Å] between selenium and the [NbCl6] anion.  相似文献   

13.
Eu2SiO3Cl2 and Eu5SiO4Cl6 were prepared by reaction of EuCl2 with EuSiO3 and Eu2SiO4, respectively, Sr2SiO3Cl2: Eu2+ from mixtures of SrCO3, Eu2O3, SrCl2 · 6H2O and SiO2 under reducing conditions. The crystal structures of Eu2SiO3Cl2 [a = 1118.7(5), c = 952.6(1) pm, tetragonal, I4/m, Z = 8, R = 3.3, Rw = 3.0%] and Eu5SiO4Cl6 [a = 900.4(1), b = 1401.7(2), c = 1112.3(2) pm, β = 103.51(1)°, monoclinic, C2/c, Z = 4, R = 3.6, Rw = 2.6%] were determined from four-circle diffractometer data and compared with related compounds. The luminescence properties were investigated at 300 K and at 4.2 K; all compounds show intense bluish-green photoluminescence. Sr2SiO3Cl2:Eu2+ shows thermoluminescence.  相似文献   

14.
Ca3Cl2CBN, a Compound with the New CBN4? Unit The new compound Ca3Cl2CBN was obtained from the reaction of Ca and CaCl2 with CaCN2, B and C or with BN and C, in sealed tantalum containers at 900°C. The crystal structure is related with the structure of Ca3Cl2C3 whereas the C34? units (C2v symmetry) are substituted by isoelectronic CBN4? anions (Cs symmetry): Ca3Cl2CBN, Pnma, a = 1 386.7(9) pm, b = 384.7(3) pm, c = 1 124.7(6) pm, Z = 4; R = 0.055, Rw = 0.036 for 380 independent intensities. The CBN4? units are located between layers of Ca2+ that are interconnected by Cl?. The bond angle (C? B? N) is 176° and bond distances are dC? B = 144 pm and dB? N = 138 pm, respectively.  相似文献   

15.
The Cluster Azides M2[Nb6Cl12(N3)6]·(H2O)4—x (M = Ca, Sr, Ba) The isotypic cluster compounds M2[Nb6Cl12(N3)6] · (H2O)4—x (M = Ca (1) , M = Sr (2) and M = Ba (3) ) have been synthesized by the reaction of an aequeous solution of Nb6Cl14 with M(N3)2. 1 , 2 and 3 crystallize in the space group Fd3¯ (No. 227) with the lattice constants a = 1990.03(23), 2015.60(12) and 2043, 64(11) pm, respectively. All compounds contain isolated 16e clusters whose terminal positions are all occupied by orientationally disordered azide ligands.  相似文献   

16.
Quaternary Chlorides of Divalent Europium and Trivalent Transition Metal Ions: Synthesis and Crystal Structure of Na6Eu3M4Cl24 (M = Ti, V, Cr) The reaction of EuCl2, NaCl and MCl3 (M = Ti, V, Cr) yields the chlorides Na6Eu3M4Cl24. According to X‐ray single crystal investigations, their crystal structure is a variant of the monoclinic cryolite‐type structure. One crystallographic site is occupied by Na1 and Eu simultaneously. For charge compensation the Na2 site is not fully occupied. In Na6Eu3Ti4Cl24 (P21/n, Z = 1/2, a = 663.8(1) pm, b = 718.3(1) pm, c = 953.3(2) pm, β = 91.55(2)°, Rall = 0.0314), Na6Eu3V4Cl24 (P21/n, Z = 1/2, a = 660.4(1) pm, b = 715.8(1) pm, c = 946.5(2) pm, β = 91.41(2)°, Rall = 0.0313) and Na6Eu3Cr4Cl24 (P21/n, Z = 1/2, a = 654.8(1) pm, b = 706.5(1) pm, c = 945.4(2) pm, β = 91.07(2)°, Rall = 0.0368) the ratio of Na1 : Eu amounts to 5 : 3. The colours of the compounds, orange yellow for M = Ti, orange red for M = V and dark red for M = Cr, indicate electronic interactions between Eu2+ and M3+.  相似文献   

17.
The Crystal Structures of the Dicesium Dodecahalogeno-closo-Dodecaborates Cs2[B12X12] (X = Cl, Br, I) and their Hydrates The perhalogenated derivatives Cs2[B12X12] (X = Cl - I) have been synthesized by reaction of Cs2[B12H12] with the respective elemental halogens (Cl2, Br2 and I2). Upon recrystallization from aqueous solution colourless, face-rich single crystals of the dihydrates (Cs2[B12X12] · 2 H2O) are obtained first which can be dehydrated topotactically via the monohydrates (Cs2[B12X12] · H2O) leaving to the solvent-free compounds (Cs2[B12X12]) behind without loss of their crystallinity. The ionic cesium salts were characterized by single crystal X-ray diffraction. All three halogenoborates are isostructural and they crystallize at room temperature in the trigonal space group (Cs2[B12Cl12]: a = 959.67(3) pm, c = 4564.2(2) pm; Cs2[B12Br12]: a = 997.92(3) pm, c = 4766.4(3) pm; Cs2[B12I12]: a = 1047.05(4) pm, c = 5018.3(3) pm; Z = 6). The crystal structures consist of a cubic closest packed host lattice formed by two crystallographically inequivalent quasi-icosahedral [B12X12]2- anions (Cs2[B12Cl12]: d(B-B) = 178 - 179 pm, d(B-Cl) = 179 - 180 pm; Cs2[B12Br12]: d(B-B) = 176 - 180 pm, d(B-Br) = 195 - 197 pm; Cs2[B12I12]: d(B-B) = 177 - 182 pm, d(B-I) = 214 - 217 pm). By ordered occupation of half of the tetrahedral and formally all octahedral interstices in every intermediate layer with Cs+ cations, a structure emerges where (Cs1)+ is trigonally non-planar coordinated by three (CN = 9) and (Cs2)+ tetrahedrally coordinated by four (CN = 12) [B12X12]2- anions. Thereby triangular faces of halogen atoms of the icosahedral clusters are coordinatively effective in both cases. In their mono- and dihydrates the incomplete coordination sphere of (Cs1)+ is completed by one and two water molecules, respectively. The thermal decomposition of the dicesium dodecahalogeno-closo-dodecaborate hydrates and their dehydration products was investigated using DTA/TG methods in a temperature range between room temperature and 1200 °C. Additionally the compounds were also characterized by 11B-NMR spectroscopy in aqueous solution.  相似文献   

18.
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   

19.
On the A2?2xSn5+xCl12 (A = K, In) Phases The refinement of the structure of A2-2xSn5+xCl12 compounds (A = K+, In+) with single crystal data is reported. They crystallize with the Th7S12 type arrangement (a = 1192(2) pm, c = 428.9(8) pm (K-compound); a = 1189.8(6) pm, c = 431.2(3) pm (In-compound)) for which we propose the space group P6 . The possibility of meroedric twinning is discussed. Due to the composition of these compounds the structure is necessarily disordered and this leads to a wide range of homogeneity which can be influenced by the size and the polarity of the A type cation.  相似文献   

20.
Crystals of ordered Ba6EuF12Cl2 were found to form during high temperature flux growth. The structure was refined in the hexagonal space group P 6 to RF(R ) = 0.024(0.024) for 326 reflections and 46 parameters. Lattice parameters are a = b = 1059.27(8) pm and c = 416.36(2) pm; Z = 1. The structure is isotypic to Ba7F12Cl2. No solid solution of Ba/Eu was observed, the Eu2+ ions are located in the channels formed by 3 + 6 fluorine ions, occupying only one of the three metal sites of the Ba7F12Cl2 structure.  相似文献   

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