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1.
Anhydrous Rare-Earth Acetates, M(CH3COO)3 (M = Sm? Lu, Y) with Chain Structures. Crystal Structures of Lu(CH3COO)3 and Ho(CH3COO)3 Single crystals of the anhydrous rare-earth acetates containing lutetium (type 1) and holmium (type 2) were obtained by crystallisation at 120°C from diluted acetic acid solutions of their oxides and cesium acetate. The crystal structures [Lu(CH3COO)3: orthorhombic, a = 825.85(8), b = 1 398.1(2), c = 823.9(1) pm, Vm = 143.24(3) cm3/mol, space group Ccm21 (No. 36), Z = 4, R = 0.035, Rw = 0.030; Ho(CH3COO)3: monoclinic, a = 1 109.1(3), b = 2 916.3(10), c = 786.8(2) pm, β = 131.90(1)°, Vm = 142.58(8) cm3/mol, space group C2/c (No. 15), Z = 8, R = 0.039, Rw = 0.039, Rw = 0.026] were determined from four-circle diffractometer data sets. The structures consist of one-dimensional infinite chains built up by bridging acetate ions. Ho3+ is coordinated by 8 oxygen atoms, whereas Lu3+ has only 7 nearest oxygen neighbours. The chains are stacked parallel to the [001] direction. Isotypic compounds with Tm? Lu (type 1) and Sm? Er, Y (type 2) were prepared as powders and characterized by X-ray powder patterns. Thermoanalytical investigations (DTA, Guinier-Simon technique) of all compounds have shown that there is a first-order phase transition at 180°C (type 2) and in the range of 230–255°C (type 1). The high-temperature phase crystallizes with the known Sc(CH3COO)3 structure (type 0) where the rare earth cations are surrounded by 6 oxygen atoms. In the case of the type 1 compounds the phase transition is reversible.  相似文献   

2.
Anhydrous Lanthanum Acetate, La(CH3COO)3, and its Precursor, ·NH4)3[La(CH3COO)6] · 1/2 H2O: Synthesis, Structures, Thermal Behaviour Single crystals of (NH4)3[La(CH3COO)6] · ½ H2O are obtained by refluxing La2O3in (CH3COO)3 · 1.5 H2O with an excess of NH4CH3COO in methanol. The crystal structure (trigonal, R3 , Z = 6, a = 1 365.0(3) pm, c = 2 360(1) pm, R = 0.088, Rw = 0.061 exhibits the coordination number of nine for La3+, which is surrounded by three chelating-type bidentate and three unidentate acetate groups. Characteristic are monomeric units of [La(CH3COO)6]3? which are connected to a three-dimensional network by hydrogen bonds with the NH ions. Thermal decomposition consists of four steps with La(CH3COO)3, La2(CO3)3 and La2O2CO3 as intermediates and La2O3 as the final Product. Single crystals of La(CH3COO)3 are obtained from La2O3 in a melt of NH4CH3COO (molar ratio 1:12) in a sealed glass ampoule. The crystal structure (trigonal, R3 , Z = 18, a = 2 203.0(5) pm; c = 987.1(3) pm, R = 0.027, Rw = 0.023) shows the coordination number of ten for La3+. These are three-dimensionally connected by oxygen atoms of the acetate groups with two tetradentate double-bridging and one Z,Z-type-bridging bidentate acetate group.  相似文献   

3.
Synthesis and Crystal Structure of Praseodymium Propionate Trihydrate, Pr(CH3CH2COO)3(H2O)3 Single crystals of Pr(CH3CH2COO)3(H2O)3 were obtained by dissolving freshly prepared praseodymium hydroxide in diluted propionic acid. The crystal structure (monoclinic, P21/c, Z = 4, a = 1034.2(2) pm, b = 1521.2(3) pm, c = 2086.3(7) pm, β = 102.87(2)°, R1 = 0.0864, wR2 = 0.1196) consists of one-dimensional infinite chains parallel [010]. Pr1 and Pr2 are coordinated by four tridentate-bridging propionate groups. Additionally, Pr1 is coordinated by three “coordination water” molecules, Pr2 by two bidentate propionate groups. There are, in addition, three “crystal water” molecules so that praseodymium propionate trihydrate should be formulated as [(H2O)3Pr1(CH3CH2COO)4Pr2(CH3CH2COO)2] (H2O)3.  相似文献   

4.
Preparation and Crystal Structures of Silver(I) Mixed Ligand Complexes with Bibenzimidazole and Triphenylphosphane: [Ag(PPh3)2(bbimH2)](COOCH3) · 2 CH2Cl2 and [{Ag(PPh3)2}2(μ-bbim)] · 4 CH2Cl2 The title compounds are obtained from silver acetate, 2,2′-bibenzimidazole and PPh3. They are characterized by their IR, 1H-NMR, 31P-NMR spectra and crystal structure determinations. [Ag(PPh3)2(bbimH2)](COOCH3) · 2 CH2Cl2: Reaction in CH2Cl2. Space group C2/c, Z = 4, 3129 observed unique reflections, R = 0.033. Lattice parameters at 203 K: a = 1450.8; b = 1556.2; c = 2316.4 pm; β = 99.69°. The crystal structure is built up by monomeric molecules with distorted tetrahedral coordination of the silver atom (AgP2N2) and bibenzimidazole as a bidentate ligand. The acetate ion is linked to the NH-groups of the bibenzimidazole by hydrogen bonds. [{Ag(PPh3)2}2(μ-bbim)] · 4 CH2Cl2: Reaction in fused PPh3 at 180 °C. Space group P 1, Z = 1. 9227 observed unique reflections, R = 0.051. Lattice parameters at 203 K: a = 1276.5; b = 1352.1; c = 1408.1 pm; α = 96.97; β = 115.87; γ = 96.84°. The crystal structure is built up by centrosymmetric molecules with distorted tetrahedral coordination of the silver atoms (AgN2P2) and bibenzimidazolate(2–) as tetradentate bridging ligand.  相似文献   

5.
M(H2O)2(4,4′‐bipy)[C6H4(COO)2]·2H2O (M = Mn2+, Co2+) – Two Isotypic Coordination Polymers with Layered Structure Monoclinic single crystals of Mn(H2O)2(4,4′‐bipy)[C6H4(COO)2]·2H2O ( 1 ) and Co(H2O)2(4,4′‐bipy)[C6H4(COO)2]· 2H2O ( 2 ) have been prepared in aqueous solution at 80 °C. Space group P2/n (no. 13), Z = 2; 1 : a = 769.20(10), b = 1158.80(10), c = 1075.00(10) pm, β = 92.67(2)°, V = 0.9572(2) nm3; 2 : a = 761.18(9), b = 1135.69(9), c = 1080.89(9) pm, β = 92.276(7)°, V = 0.9337(2) nm3. M2+ (M = Mn, Co), which is situated on a twofold crystallographic axis, is coordinated in a moderately distorted octahedral fashion by two water molecules, two oxygen atoms of the phthalate anions and two nitrogen atoms of 4,4′‐biypyridine ( 1 : M–O 219.5(2), 220.1(2) pm, M–N 225.3(2), 227.2(2) pm; 2 : Co–O 212.7(2), 213.7(2) pm, Co–N 213.5(3), 214.9(3) pm). M2+ and [C6H4(COO)2)]2? build up chains, which are linked by 4,4′‐biyridine molecules to yield a two‐dimensional coordination polymer with layers parallel to (001).Thermogravimetric analysis in air of 1 indicated a loss of water of crystallization between 154 and 212 °C and in 2 between 169 and 222 °C.  相似文献   

6.
Crystal Structures of [Ph3PMe]Cl·CH2Cl2, [Ph4P]NO3·CH2Cl2, and [Ph4P]2[SiF6]·CH2Cl2 The crystal structures of the title compounds are determined by X‐ray diffraction. In all cases, the included dichloromethane molecules as well as the phosphonium cations are involved to form hydrogen bridges with the anions. [Ph3PMe]Cl·CH2Cl2 ( 1 ): Space group , Z = 2, lattice dimensions at 100 K: a = 890.3(1), b = 988.0(1), c = 1162.5(1) pm, α = 106.57(1)°, β = 91.79(1)°, γ = 92.60(1)°, R1 = 0.0253. [Ph4P]NO3·CH2Cl2 ( 2 ): Space group P21/n, Z = 4, lattice dimensions at 193 K: a = 1057.0(1), b = 1666.0(1), c = 1358.9(1) pm, β = 100.10(1)°, R1 = 0.0359. [Ph4P]2[SiF6]·CH2Cl2 ( 3 ): Space group , Z = 2, lattice dimensions at 193 K: a = 1063.9(1), b = 1233.1(1), c = 1782.5(2) pm, α = 76.88(1)°, β = 83.46(1)°, γ = 72.29(1)°, R1 = 0.0332.  相似文献   

7.
Ternary Acetates of the Lanthanides with Cesium: Dimers in CsLu(CH3COO)4 and Trimers in Cs2[Lu3(CH3COO)10(OH)(H2O)]. Synthesis, Crystal Structures, Thermolysis Single crystals of CsLu(CH3COO)4 and Cs2[Lu3(CH3COO)10(OH)(H2O)] were obtained from an aqueous solution of lutetium and cesium acetate in a 1:1 molar ratio. The crystal structures (CsLu(CH3COO)4: monoclinic, P21/n (no. 14), Z = 8, a = 1 293.1(2), b = 1 323.8(2), c = 1 622.5(3) pm, β = 92.01(2)°, Vm = 208.97(6) cm3/mol, R = 0.056, Rw = 0.034; Cs2[Lu3(CH3COO)10(OH)(H2O)]: monoclinic, C2/c (no.15), Z = 4, a = 2 138.5(6), b = 1 378.0(3), C = 1 482.9(4) pm, β = 106.15(2)°, Vm = 632.0(3) cm3/mol, R = 0.049, Rw = 0.036) were determined from four-circle-diffractometer data. The structures consist of dimers and trimers, respectively, that are built by bridging acetate groups. These units are fragments of the infinite chains of the Ho(CH3COO)3 type of structure. The isotypic compounds CsM(CH3COO)4 with M=Eu? Lu were synthesized and characterized by the X-ray Guinier technique. The thermal decomposition of CsLu(CH3COO)4 was examined with thermoanalytical methods (TG/DSC with coupled gas analysis) and the Guinier-Simon technique: it decomposes at 260°C in an endothermic reaction to Lu2O3 and Cs2CO3.  相似文献   

8.
Cs2(H3O)Pr(CH3COO)6 and Cs2Pr(CH3COO)5: Synthesis, Crystal Structures and Thermolysis. Analogous Acetates with Lanthanum through Terbium Single crystals of Cs2(H3O)Pr(CH3COO)6 are obtained as green plates from an acetic acid solution (≈50%) of Cs2CO3 and Pr(CH3COO)3 · 1,5 H2O. The crystal structure monoclinic, Cm, Z = 2, a = 1 540.4(4), b = 691.3(2), c = 1 221.5(4) pm, β = 104.60(5)°, Vm = 379.1(2) cm3/mol, R = 0.040, Rw = 0.035 was determined from four-circle-diffractometer data. The structure consists of monomeric Pr(CH3COO)3 units, in which Pr3+ is surrounded by nine oxygen atoms. These monomers are linked together to infinite layers parallel (001) by common acetate oxygen atoms with two ?molecules”? of Cs(CH3COO). Together with an additional acetate ion coordinated to one of the Cs+ ions the composition of the layers is [Cs2Pr(CH3COO)6]?. Between these layers H3O+ is located for electroneutrality. Thermal decomposition of Cs2(H3O)Pr(CH3COO)6 was examined with thermoanalytical methods (TG/DTA with coupled gas analysis), Guinier-Simon technique and IR spectroscopy: beginning at 70°C the compound looses water and acetic acid. It decomposes topotactically to Cs2Pr(CH3COO)5. At 270°C this acetate decomposes to Cs2CO3 and Pr2O2CO3 which emits CO2 at 600°C form ing Pr2O3or PrO2?x Single crystals of Cs2Pr(CH3COO)5 were obtained from Pr(CH3COO)3, in molten Cs(CH3COO) at about 200°C. The crystal structure tetragonal, P43, Z = 4, a = 1 174,5(2), c = 1 480,5(3) pm, Vm = pin,307,5(1) cm3/mol, R = 0,061, Rw= 0,031 again consists of Pr(CH3COO)3, monomers where Pr3+ has 9 oxygen ligands in its first coordination sphere. They are linked together by two ”molecules“ of cesium acetate to infinite chains along [00l] around the 4, screw axis. There are also acetate bridges between these chains. Isotypic compounds Cs2(H3O)M(CH3COO)6 and Cs2M(CH3COO)5, and Cs2M(CH3COO)5with M = La? Tb, were obtained from acetic acid solutions or thermal decomposition and were characterized by X-ray Guinier techniques.  相似文献   

9.
Pr(CH3COO)3, an Anhydrous Rare-Earth Acetate with a Network Structure Pr(CH3COO)3 may be prepared by dehydration of Pr(CH3COO)3 · 1,5 H2O at 180°C as an amorphous green powder. Single crystals were grown from the powder by addition of (NH4)CH3COO as ?mineralisator”? at 180°C in a sealed glass ampoule. The crystal structure (tetragonal, P4 21c (no. 114), Z = 24, a = 2106.5(3), c = 1323.6(1) pm, Vm = 147.39(3) cm3/mol, R = 0.055, Rw = 0.029) was determined from four-circle-diffractometer data. The Pr3+ ions occupy three crystallographically independent positions and are surrounded by 9 and 10 oxygen atoms, respectively. Acetate ions connect the cations to a complicated three-dimensional network.  相似文献   

10.
Crystal Structures of (Ph4P)2[HfCl6]·2CH2Cl2 and (Ph4P)2[Hf2Cl10]·CH2Cl2 Colourless single crystals of (Ph4P)2[HfCl6]·2CH2Cl2 ( 1 ) and (Ph4P)2[Hf2Cl10]·CH2Cl2 ( 2 ) were obtained from hafniumtetrachloride and tetraphenylphosphonium chloride in dichloromethane solution, using the corresponding stoichiometry of the educts. Both compounds were characterized by X‐ray structure determinations. 1 : Space group P1¯, Z = 1, lattice dimensions at 193 K: a = 1018.3(1), b = 1121.0(1), c = 1240.1(1) pm, α = 70.55(1)°, β = 81.38(1)°, γ = 80.02(1)°, R1 = 0.0374. 2 : Space group P1¯, Z = 1, lattice dimensions at 193 K: a = 1124.4(1), b = 1141.9(1), c = 1281.4(1) pm, α = 63.80(1)°, β = 68.15(1)°, γ = 86.33(1)°, R1 = 0.0208.  相似文献   

11.
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   

12.
Synthesis and Crystal Structure of the Adducts [DB-18C6] · CH3CN · CH3CSOH and [DC-18C6](CH3CSOH)2 as well as of the Salt-like Compounds [Cs(B-15C5)2]CH3CSS and [Cs(DB-18C6)]2S5(DMF)21) The reaction products of crown ethers, cesium, and sulfur in aprotic solvents like acetonitrile and dimethylformamide strongly depend on the reaction conditions. Using CH3CN as a solvent, sometimes neutral host-guest adducts crystallize only, e.g., [dibenzo-18C6] · CH3CN · CH3CSOH (monoclinic, S. G. P21/c, Z = 4, a = 9.73(1) Å, b = 22.03(1) Å, c = 11.86(1) Å, β = 91.8(1)°) or [dicyclohexyl-18C6](CH3CSOH)2 (monoclinic, S. G. P21/n, Z = 2, a = 7.75(1) Å, b = 10.32(1) Å, c = 17.73(1) Å, β = 95.7(1)°). The monothioacetic acid, CH3CSOH, must be regarded as the first product of the hydrolysis of CH3CN. Furthermore, another product of this kind of hydrolysis, CH3CSSH, is obtained too. Therefore, we also obtain the salt-like compound [Cs(benzo-15C5)2]CH3CSS (monoclinic, S. G. C2/c, Z = 4, a = 16.05(1) Å, b = 16.73(1) Å, c = 13.11(1) Å, β = 106.3(1)°). If the solvent DMF is used, the pentasulfide [Cs(dibenzo-18C6)]2S5(DMF)2 crystallizes (monoclinic, S. G. P21/n, Z = 4, a = 14.79(1) Å, b = 14.24(1) Å, c = 25.74(1) Å, β = 92.7(1°. The S52? anions show the cis-conformation.  相似文献   

13.
Synthesis and Molecular Structure of Barium Bis[N,N′-bis(trimethylsilyl)benzamidinate] ° DME ° THF Barium bis[N,N′-bis(trimethylsilyl)benzamidinate] · thf · dme crystallizes in the monoclinic space group P21/n with a = 1 122.0(2), b = 2 190.7(4), c = 1 840.2(3) pm, β = 98.04(1)° and Z = 4 containing a metal center in a distorted monocapped trigonal prismatic surrounding. The barium dibenzamidinate moiety is sent with an angle of 120°, although this leads to different Ba? N distances of 273 and 282 pm originating from the interligand repulsion of the trimethylsilyl groups and the dme substituent. The 1,3-diazaallyl fragment with C? N bond lengths of 132 pm shows a delocalisation of the anionic charge.  相似文献   

14.
Reactions of Uranium Pentabromide. Crystal Structures of PPh4[UBr6], PPh4[UBr6] · 2CCl4, (PPh4)2[UBr6] · 4CH3CN, and (PPh4)2[UO2Br4] · 2CH2Cl2 PPh4[UBr6] and PPh4[UBr6] · 2CCl4 were obtained from UBr5 · CH3CN and tetraphenylphosphonium bromide in dichloromethane, the latter being precipitated by CCl4. Their crystal structures were determined by X-ray diffraction. PPh4[UBr6]: 2101 observed reflexions, R = 0.090, space group C2/c, Z = 4, a = 2315.5, b = 695.0, c = 1805.2 pm, β = 96.38°. PPh4[UBr6] · 2CCl4: 2973 reflexions, R = 0.074, space group P21/c, Z = 4, a = 1111.5, b = 2114.2, c = 1718.7 pm, β = 95.42°. Hydrogen sulfide reduces uranium pentabromide to uranium tetrabromide. Upon evaporation, bromide is evolved from solutions of UBr5 with 1 or more then 3 mol equivalents of acetonitrile in dichlormethane yielding UBr4 · CH3CN and UBr4 · 3CH3CN, respectively. These react with PPh4Br in acetonitrile affording (PPh4)2[UBr6] · 4CH3CN, the crystal structure of which was determined: 2663 reflexions, R = 0.050, space group P21/c, Z = 2, a = 981.8, b = 2010.1, c = 1549.3 pm, β = 98.79°. By reduction of uranium pentabromide with tetraethylammonium hydrogen sulfide in dichloromethane (NEt4)2[U2Br10] was obtained; (PPh4)2[U2Br10] formed from UBr4 and PPh4Br in CH2Cl2. Both compounds are extremely sensitive towards moisture and oxygen. The crystal structure of the oxydation product of the latter compound, (PPh4)2[U02Br4]· 2 CH2Cl2, was determined: 2163 reflexions, R = 0.083, space group C2/c, Z = 4, a = 2006.3, b = 1320.6, c = 2042,5 pm, β = 98.78°. Mean values for the UBr bond lengths in the octahedral anions are 266.2 pm for UBr6-, 276.7 pm for UBr62? and 282.5 pm for UO2Br42?  相似文献   

15.
Studies on Polyhalides. 16. Preparation and Crystal Structures of Bipyridiniumpolyiodides Bipy · HIn with n = 3, 5, and 7 With simply protonated α,α′-Bipyridyl Bipy · H+ a triiodide Bipy · HI3, a pentaiodide Bipy · HI5 and a heptaiodide Bipy · HI7 may be prepared in the presence of iodide ions I? and dependent of the iodine I2 content. Bipyridiniumtriiodide C10H9N2I3 crystallizes at room temperature monoclinically in P21/n with a = 1 122.8(1) pm, b = 1 072.7(1) pm, c = 1 200.2(3) pm, β = 98.02(2)° and Z = 4. The crystal structure is built up from mixed cationic and anionic layers. Bipyridiniumpentaiodide C10H9N2I5 crystallizes at room temperature monoclinically in P21/c with a = 887.3(5) pm, b = 2 527.9(12) pm, c = 830.7(3) pm, β = 106.78(5)° and Z = 4. The crystal structure contains triiodide ions I3? till now uniquely connected by iodine molecules I2 in a trigonal planar way. Bipyridiniumheptaiodide C10H9N2I7 crystallizes at room temperature triclinically in P&1macr; with a = 713.1(3) pm, b = 1 007.9(3) pm, c = 1 464,8(4) pm, α = 81.07(3)°, β = 89.92(3)°, γ = 82.77(3)° and Z = 2. The crystal structure contains a V-shaped pentaiodide ion I5? completed by an iodine molecule I2 to a trigonal pyramidally shaped heptaiodide ion I7? and at the same time connected to a zigzag chain.  相似文献   

16.
Synthesis and Crystal Structure of [WNCl3 · NCPh]4 · 3 CH2Cl2 The adduct of tungsten nitride trichloride with benzonitrile, [WNCl3 · NCPh]4, is formed by the reaction of N,N,N'-tris(trimethylsilyl)benzamidine and tungsten hexachloride in CCl4 solution. It forms red crystal needles and was characterized by its IR spectrum and an X-ray crystal structure determination (1983 unique observed reflexions, R = 0.075). Crystal data: a = 1464.8, b = 1902.6, c = 2033.8 pm, β = 102.27°, space group C2/c, Z = 4. In the [WNCl3 · NCPh]4 molecule the tungsten atoms were located at the vertices of a square and are linked with one another via linear W?N? W nitrido bridges with alternating short and long bonds having average lengths of 166 and 211 pm. The N atoms of the benzonitrile ligands are in the positions trans to the W?N bonds at distances of 237 pm.  相似文献   

17.
Synthesis, Vibrational Spectra, and Crystal Structures of the Nitrato Argentates (Ph4P)[Ag(NO3)2(CH3CN)]·CH3CN and (Ph4P)[Ag2(NO3)3] Tetraphenylphosphonium bromide reacts in acetonitril suspension with excess silver nitrate to give (Ph4P)[Ag(NO3)2(CH3CN)]·CH3CN ( 1 ), whereas (Ph4P)[Ag2(NO3)3] ( 2 ) is obtained in a long‐time reaction from (Ph4P)Br and excess AgNO3 in dichloromethane suspension. Both complexes were characterized by vibrational spectroscopy (IR, Raman) and by single crystal structure determinations. 1 : Space group P21/c, Z = 4, lattice dimensions at 193 K: a = 1781.5(3), b = 724.8(1), c = 2224.2(3) pm, β = 96.83(1)°, R1 = 0.0348. 1 contains isolated complex units [Ag(NO3)2(CH3CN)]?, in which the silver atom is coordinated by the chelating nitrate groups and by the nitrogen atom of the solvated CH3CN molecule with a short Ag—N distance of 220.7(4) pm. 2 : Space group I2, Z = 4, lattice dimensions at 193 K: a = 1753.4(4), b = 701.7(1), c = 2105.5(4) pm, R1 = 0.072. In the polymeric anions [Ag2(NO3)3]? each silver atom is coordinated in a chelating manner by one nitrate group and by two oxygen atoms of two bridging nitrate ions. In addition, each silver atom forms a weak π‐bonding contact with a phenyl group of the (Ph4P)+ ions with shortest Ag···C separations of 266 and 299 pm, respectively, indicating a (4+1) coordination of silver atoms.  相似文献   

18.
Crystal Structures, Vibrational Spectra, and Normal Coordinate Analyses of the Chloro-Iodo-Rhenates(IV) (CH2Py2)[ReCl5I], cis -(CH2Py2)[ReCl4I2] · 2 DMSO, trans -(CH2Py2)[ReCl4I2] · 2 DMSO, and fac -(EtPh3P)2[ReCl3I3] [ReCl5I]2–, cis-[ReCl4I2]2–, trans-[ReCl4I2]2–, and fac-[ReCl3I3]2– have been synthesized by ligand exchange reactions of [ReI6]2– with HCl and are separated by ion exchange chromatography on diethylaminoethyl cellulose. X-ray structure determinations have been performed on single crystals of (CH2Py2)[ReCl5I] ( 1 ) (triclinic, space group P1 with a = 7.685(2), b = 9.253(2), c = 12.090(4) Å, α = 90.06(2), β = 101.11(2), γ = 95.07(2)°, Z = 2), cis-(CH2Py2)[ReCl4I2] · 2 DMSO ( 2 ) (triclinic, space group P1 with a = 8.662(2), b = 12.109(2), c = 12.9510(12) Å, a = 97.533(11), β = 96.82(2), γ = 89.90(2)°, Z = 2) , trans-(CH2Py2)[ReCl4I2] · 2 DMSO ( 3 ) (triclinic, space group P1 with a = 9.315(7), b = 9.663(3), c = 15.232(3) Å, α = 80.09(2), β = 81.79(4), γ = 83.99(5)°, Z = 2) and fac-(EtPh3P)2[ReCl3I3] ( 4 ) (monoclinic, space group P21/a with a = 17.453(2), b = 13.366(1), c = 19.420(1) Å, β = 112.132(8)°, Z = 4). The crystal structure of ( 1 ) reveals a positional disorder of the anion sublattice along the asymmetric axis. Due to the stronger trans influence of I compared with Cl on asymmetric axes Cl˙–Re–I′ is caused a mean lenghthening of the Re–Cl˙ distances of 0.020 Å (0.8%) and a shortening of the Re–I′ distances of 0.035 Å (1.3%) with regard to symmetrically coordinated axes Cl–Re–Cl and I–Re–I, respectively. Using the molecular parameters of the X-Ray determinations the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salts of all four chloro-iodo-rhenates(IV) are assigned by normal coordinate analyses. The weakening of the Re–Cl˙ bonds and the strengthening of the Re–I′ bonds is indicated by a decrease or increase of the valence force constants each by 9%.  相似文献   

19.
Alkaline Earth Fluoromanganates(III): BaMnF5 · H2O and SrMnF5 · H2O Solid BaF2 or SrF2 forms with solutions of Mn3+ in aqueous hydrofluoric acid precipitates of hitherto unknown BaMnF5 · H2 and SrMnF5 · H2O respectively. X-ray structure determination on single crystals of both isotypic compounds (space group P21/m, Z = 2; BaMnF5 · H2O: a = 537.0(3), b = 817.2(2), c = 628.0(4) pm β = 111.17(5)°, Rw = 0.035 for 1403 reflections; SrMnF5 · H2O: a = 510.8(1), b = 792.0(2), c = 610.6(1) pm, β = 110.24(1)° Rw = 0.068 for 539 reflections) reveal pure [MnF6]3? octahedra connected with each other to infinite chains by sharing trans corners. The H2O molecules are coordinated to the alkaline earth ions only and form weak O? H…F hydrogen bonds. The pronounced weakening of the Mn? F bonds within the chain direction (Mn? F 2X 212.7(1)/210.8(5) pm, 2X 183.8(3)/181.8(9) pm, 2X 186.9(2)/187.2(8) pm) may be due by halves to the Jahn-Teller-effect as can be deduced by bond valence calculations.  相似文献   

20.
Pyridine Complexes of Rare Earth Element Trichlorides. Syntheses and Crystal Structures of [YCl3(py)4] and [LnCl3(py)4] · 0.5 py with Ln = La and Er The pyridine complexes [YCl3(py)4] ( 1 ), [LaCl3(py)4] · 0.5 py ( 2 · 0.5 py), and [ErCl3(py)4] · 0.5 py ( 3 · 0.5 py) have been prepared from the diacetone‐alcohol complexes [LnCl3(DAA)2] or directly from the metal trichlorides with excess pyridine to give colourless, only sparingly moisture sensitive crystals. They were characterized by IR spectroscopy and by crystal structure determinations. 1 : Space group Pbca, Z = 16, lattice dimensions at –80 °C: a = 1647.4(1), b = 1743.1(1), c = 3190.5(1) pm, R1 = 0.031. 2 · 0,5 Py: Space group P21/n, Z = 4, lattice dimensions at –80 °C: a = 978.9(1), b = 1704.5(1), c = 1589.5(1) pm, β = 103.61(1)°, R1 = 0.0281. 3 · 0,5 Py: Space group P21/n, Z = 4, lattice dimensions at –80 °C: a = 970.1(1), b = 1706.4(1), c = 1566.1(1) pm, β = 103.46(1)°, R1 = 0.0232. All complexes realize monomeric molecular structures with the metal atom in a distorted pentagonal‐bipyramidal coordination. One of the chlorine atoms and the four pyridine molecules are in the equatorial plane.  相似文献   

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