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1.
Zusammenfassung Das -Isomer des Antimontribenzoats kristallisiert rhomboedrisch (hexagonale Aufstellung) in der Raumgruppe R3 mita=1944.0 pm,c=422.3 pm undZ=3. Die Moleküle sind parallel zu 001 gestapelt. Sb hat gegenüber O die Koordinationszahl 3+3 (Sb-O: 208 bzw. 256 pm).
Antimonytribenzoate
Summary The isomer of (C6H5CO2)3Sb crystallizes rhombohedrally (hexagonal axes) in the space group R3 witha=1944.0 pm,c=422.3 pm, andZ=3. The molecules are stacked parallel to 001; Sb has a coordination number of 3+3 (Sb-O: 208 and 256 pm, resp.).
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2.
Zusammenfassung Arsen-tris(trifluoracetat) (1) kristallisiert monoklin in der Raumgruppe Cc mita=1229.3,b=1697.9,c=1243.5 pm, =110.01° undZ=8. Die Trifluoracetatanionen fungieren gegenüber As als zweizähnige Liganden und verknüpfen die beiden kristallographisch unabhängigen Moleküle zusätzlich intermolekular. As erreicht dadurch gegenüber O die Koordinationszahl 3+3(+2). Die Elementarzelle enthält zwei Sätze von chirameren Molekülen.
Crystal and molecular structure of arsenictris(trifluoroacetate)
Summary Arsenictris(trifluoroacetate) (1) crystallizes monoclinic in the space group Cc witha=1229.3,b=1697.9,c=1243.5 pm, =110.01°, andZ=8. The trifluoroacetic acid ions acts as chelating ligands. Additionally they are bridging crystallographic independent molecules. As has a coordination number of 3+3(+2). The unit cell contains two sets of chirameres.
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3.
About the Structure and Reactivity of Diammonium Hexafluoromanganate(IV) Electrolytic oxidation of an aqueous suspension of MnF2 containing NH4F, and subsequent crystallization in 40% HF yields yellow crystals of (NH4)2MnF6. It crystallizes in the hexagonal K2MnF6 type structure with the space group P63mc and a = 5.903; c = 9.565 Å; Z = 2. With in situ powder diffraction studies it is shown, that (NH4)2MnF6 is gradually reduced in a NH3 atmosphere between 30 and 230 °C to afford (NH4)3MnF6, (NH4)2MnF5, and finally NH4MnF3. (NH4)3MnF6, thereby, forms a hitherto unknown cubic (a = 9.082 Å) high temperature modification with the cryolite type structure. Under N2 the thermal decomposition of (NH4)2MnF6 proceeds via NH4MnF4 to yield MnF2.  相似文献   

4.
Three Stereoisomeric Square-Pyramidal Complexes [Ma3b2]: Investigations of the Existence and the Structures of Crystalline Dimethyl Sulfoxide Complexes of Antimony and Bismuth Trichlorides The formation of solid complexes MCl3 · n DMSO (M = Sb, Bi; n = 1–4) was reinvestigated. In each system, only two of four presumptive complexes could be isolated as crystalline solids: SbCl3 · DMSO ( 1 a ) was prepared for the first time, SbCl3 · 2 DMSO ( 1 b ), BiCl3 · 2 DMSO ( 2 b ) and BiCl · 3 DMSO ( 2 c ) were reproduced according to literature data. Evidence is presented as to the non-existence of BiCl3 · 4 DMSO, contrary to previous claims in the literature. A unit cell determination showed 2 c to be structurally identical with the monomeric fac-octahedral complex BiCl3(DMSO)3 obtained fortuitously and described elsewhere [Z. anorg. allg. Chem. 620 (1994) 1037]. The compounds 1 a (monoclinic, space group P21/c), 1 b (monoclinic, space group P21/n) and 2 b (monoclinic, space group C2) represent examples of each of the three possible geometric isomers of a square-pyramidal complex [Ma3b2]. In the formally 1/1 adduct 1 a , which is in fact [Sb(1)Cl3(DMSO)2 · Sb(2)Cl3], the Sb(1) atom of the complex unit displays square-pyramidal geometry with the DMSO ligands situated in the apical and one of the basal positions. These units are linked into chains by SbCl3 molecules acting as Cl-acceptors. Sb(2) forms two chelating chloro-bridges with cis-Cl atoms of one neighbouring complex and a third chloro-bridge with the remaining Cl of the symmetry-related second neighbour. The resulting Cl6-geometry around Sb(2) is distorted octahedral. 1 b consists of square-pyramidal molecules, in which the DMSO ligands occupy two basal cis-positions; the monomeric units are loosely linked through the apical Cl atoms to form a chain of octahedra sharing trans-vertices. The asymmetric unit of 2b is a square pyramid with trans-basal DMSO ligands. The pyramids are connected by symmetry-equivalent basal chlorine atoms into chains of octahedra sharing cis-vertices. 1a displays remarkably short Sb? O dative bonds (204.7/212.9 pm); the M? O bond distances of 1b and 2b are 223.0/234.6 and 234.5/238.7 pm, respectively.  相似文献   

5.
《Analytical letters》2012,45(2):351-363
Abstract

A systematic study on the reduction of Sb(III) on a mercury electrode in aqueous solution of tartrate ion has been carried out. The nature of the electrode reactions has shown to be a function of the acidity of the solution. Results from polarographic, coulometric and voltammetric experiments allow us to outline a model of electrode reaction according to which different Sb-tartrate complex ions can be reduced. Sensitivity and detection limits for the polarographic determination of Sb(III) in tartrate medium are given using several polarographic waves obtained at different pH. In this way, the selection of the basic medium is vindicated.  相似文献   

6.
Synthesis and Structure of K3N Two phases in the binary system K/N have been obtained via co‐deposition of potassium and nitrogen onto polished sapphire at 77 K and subsequent heating to room temperature. The powder diffraction pattern of one of these phases can be satisfactorily interpreted by assuming the composition K3N, and the anti‐TiI3 structure‐type, which is also adopted by Cs3O. The resulting hexagonal lattice constants are: a = 779.8(2), c = 759.2(9) pm, Z = 2, P63/mcm. Comparison with possible structures of K3N generated by computational methods and refined at Hartree‐Fock‐ and DFT level, reveals that the energetically most favoured structure has not formed (presumable Li3P‐type), but instead one of those with very low density. In this respect, the findings for K3N are analogous to the results on Na3N. The thermal evolution of the deposited starting mixture has been investigated. Hexagonal K3N transforms to another K/N phase at 233 K. Its XRD can be fully indexed resulting in an orthorhombic cell a = 1163, b = 596, c = 718 pm. Decomposition leaving elemental potassium as the only residue occurs at 263 K.  相似文献   

7.
ReCl4(PPh3)2 – Reactions and Structure The compounds ReCl4(PPh3)2 and Re2OCl3(C2H5COO)2(PPh3)2 resulting from the reaction of ReOCl3(PPh3)2 with PPh3 in boiling propionic acid and HCl atmosphere were characterized by their VIS-spectra and structural data. Ligand exchange reactions with acetylacetone gave ReCl2(acac)2 as well as ReCl2(acac)(PPh3)2. Crystallographic data see “Inhaltsübersicht”.  相似文献   

8.
Synthesis, Crystal Structures, and Vibrational Spectra of [OsBr(acac)(PPh3)] and [OsBr(acac)(AsPh3)] By reaction of tetrabromoacetylacetonatoosmate(IV) with PPh3 or AsPh3 in ethanol the complexes [OsBr(acac)(PPh3)] ( 1 ) and [OsBr(acac)(AsPh3)] ( 2 ) are formed, which are purified by chromatography on silica gel. X-ray structure determinations of single crystals of ( 1 ) (monoclinic, space group P 21/n, a = 13.035(2), b = 18.2640(14), c = 16.636(3) Å, β = 112.776(14)°, Z = 4) and ( 2 ) (monoclinic, space group P 21/c, a = 13.23(5), b = 18.35(2), c = 16.65(2) Å, β = 112.9(5)°, Z = 4) result in mean bond distances Os–P = 2.413, Os–As = 2.483, Os–Br = 2.488 and Os–O = 2.037 Å. The vibrational spectra (10 K) exhibit the inner ligand vibrations of the acac, PPh3 and AsPh3 groups with nearly constant frequencies and the stretching vibrations of OsP at 499–522, of OsAs at 330–339, of OsBr at 213–214 and of OsO in the range 460–694 cm–1.  相似文献   

9.
Mono- and Dinuclear Fluoro Complexes of Titanium (III), Chromium (III), and Iron(III). Syntheses and Structures of (NMe4) (Ti(H2O)4F2)TiF6 · H2O, (NMe4)3Cr2F9, and (NMe4)3Fe2F9 The title compounds have been prepared by reaction of MCl3 (M = Ti, Cr, Fe) with NMe4F in dimethylformamide. (NMe4)3Cr2F9 and (NMe4)3Fe2F9 contain the face-sharing biocathedral M2F93? unit. The M…M distances are 277.1(1) and 289.8(3) pm in (NMe4)3Cr2F9 and (NMe4)Fe2F9, respectively. (NMe4)(Ti(H2O)4F2)TiF6 · H2O contains trans-TiIII(H2O)4F2+ cations and TiIVF62? anions. Crystal data: (NMe4)3Cr2F9: hexagonal, space group P63/m, a = 804.1(3), c = 1857.5(4) pm, Z = 2, 529 reflections, R = 0.049; (NMe4)3Fe2F9: hexagonal, space group P63/m, a = 804.7(5), c = 1 861.6(5) pm, Z = 2, 635 reflections, R = 0,046; (NMe4)(Ti(H2O)4F2)TiF6 · H2O: orthorhombic, space group Pbca, a = 776.9(2), b = 1 616.3(3), c = 2 428.6(7) pm, Z = 8, 2 784 reflections, R = 0,056.  相似文献   

10.
Synthesis, Crystal Structures, and Vibrational Spectra of [OsCl(acac)(EPh3)], E = P, As, Sb By reaction of tetrachloroacetylacetonatoosmate(IV) with PPh3, AsPh3 or SbPh3 in ethanol the complexes [OsCl(acac)(EPh3)], E = P, As, Sb are formed, which are purified by chromatography on silica gel. X-ray crystal structure determinations of the isotypic single crystals of [OsCl(acac)(EPh3)] (monoclinic, space group P 21/c, Z = 4; E = P ( 1 ): a = 12.972(2), b = 18.255(2), c = 16.517(2) Å, β = 112.61(2)°; E = As ( 2 ): a = 13.173(5), b = 18.299(5), c = 16.429(5) Å, β = 112.346(5)°; E = Sb ( 3 ): a = 13.573(3), b = 18.520(3), c = 16.440(9) Å, β = 111.78(2)°) result in mean bond distances Os–P = 2.412, Os–As = 2.485, Os–Sb = 2.619, Os–Cl = 2.354 and Os–O = 2.032 Å. The IR spectra (10 K) exhibit the inner ligand vibrations of the acac and EPh3 groups with nearly constant frequencies and the stretching vibrations of OsP at 500–524, of OsAs at 330–339, of OsSb at 271–278, of OsCl at 317–322 and of Os–O in the range 460–694 cm–1.  相似文献   

11.
Synthesis, Properties, and Structure of LiAuI4 and KAuI4 with a Discussion of the Crystal Chemical Relationship between the Halogenoaurates RbAuCl4, AgAuCl4, RbAuBr4 and LiAuI4 The alkalimetal iodo aurates(III) MAuI4 (M ? Li, K) are obtained in form of single crystals from MI, Au and I2 in a sealed glass ampoule by heating to 550°C and slow cooling to 300°C. KAuI4 crystallizes in the monoclinic space group P21/c with a = 968.6(4); b = 704.5(2), c = 1393.2(7) pm; β = 100.95(2)° and Z = 4. The crystal structure is built up from square planar AuI4? anions and K+ cations. The cations are coordinated by eight I atoms of neighbouring AuI4? anions with distances K? I between 350.0 and 369.6 pm. At 100°C KAuI4 is reduced to form K3Au3I8, which at 180°C decomposes to KI, Au and I2 LiAuI4 forms black, moisture sensitive needles, decomposing in the absence of iodine at 20°C to LiI, Au and I2. It crystallizes in a variant of the RbAuBr4 type structure with the space group P21/a and a = 1511.7(4); b = 433.9(4); c = 710.0(2) pm; β = 121.50(2)°; Z = 2. The crystal chemical relationship between the structures of RbAuCl4, RbAuBr4, AgAuCl4 and LiAuI4 is discussed.  相似文献   

12.
Synthesis and Structure of Ammine and Amido Complexes of Iridium The reaction of (NH4)2[IrCl6] with NH4Cl at 300 °C in a sealed glass ampoule yields the iridium(III) ammine complex (NH4)2[Ir(NH3)Cl5], which crystallizes isotypically with K2[Ir(NH3)Cl5] in the orthorhombic space group Pnma with Z = 4, and a = 1350.0(2); b = 1028.5(3); c = 689.6(2) pm. The reaction of (NH4)2[IrCl6] with NH3 at 300 °C, however, gives the already known [Ir(NH3)5Cl]Cl2 beside a small amount of [Ir(NH3)4Cl2]Cl2. In pure form [Ir(NH3)5Cl]Cl2 is obtained by ammonolysis of (NH4)2[Ir(NH3)Cl5] at 300 °C with NH3. [Ir(NH3)4Cl2]Cl2 crystallizes triclinic (P1, Z = 1, a = 660,2(3); b = 680,4(3); c = 711,1(2) pm; α = 103,85(2)°, β = 114,54(3)°, γ = 112,75(2)°). The structure contains Cl anions and [Ir(NH3)4Cl2]2+ cations with a trans position of the Cl atoms. Upon reaction of [Ir(NH3)5Cl]Cl2 with Cl2 one ammine ligand is eliminated yielding [Ir(NH3)4Cl2]Cl, which is transformed to orthorhombic [Ir(NH3)4(OH2)Cl]Cl2 (Pnma, Z = 4, a = 1335,1(3); b = 1047,9(2); c = 673,4(2) pm) by crystallization from water. In the octahedral complex [Ir(NH3)4(OH2)Cl]2+ the four ammine ligands have an equatorial position, whereas the Cl atom and the aqua ligand are arranged axial. Oxidation of (NH4)2[Ir(NH3)Cl5] with Cl2 at 330 °C affords the tetragonal IrIV complex (NH4)[Ir(NH3)Cl5] (P4nc, Z = 2, a = 702.68(5); c = 912.89(9) pm). Its structure was determined using the powder diagram. Oxidation of (NH4)2[Ir(NH3)Cl5] with Br2 in water, on the other hand, gives (NH4)2[IrBr6] crystallizing in the K2[PtCl6] type. Oxidation of (PPh4)2[Ir(NH3)Cl5] with PhI(OAc)2 in CH2Cl2 affords the IrV amido complex (PPh4)[Ir(NH2)Cl5].  相似文献   

13.
Jitmanee K  Oshima M  Motomizu S 《Talanta》2005,66(3):529-533
A novel and simple flow-based method was developed for the simultaneous determination of As(III) and As(V) in freshwater samples. Two miniature columns with a solid phase anion exchange resin, placed on two 6-way valves were utilized for the solid-phase collection/concentration of arsenic(III) and arsenic(V), respectively. As(III) could be retained on the column after its oxidation to As(V) species with an oxidizing agent. The collected analytes were then sequentially eluted by 2 M nitric acid and introduced into ICP-AES. Potassium permanganate was examined as potential oxidizing agent for conversion of As(III) to As(V). The standard deviation of the analytical signals (peak height) for the replicate analysis (n = 5) of 0.5 μg l−1 solution were 3 and 5% for As(III) and As(V), respectively. The limit of detection (3σ) for both As(III) and As(V) were 0.1 μg l−1. The proposed system produced satisfactory results on the application to the direct analysis of inorganic arsenic species in freshwater samples.  相似文献   

14.
Polyol Metal Complexes. 33 [1] Structure of a Homoleptic Bis-xylitolato(5–) Dicobaltate(III) Dark-green crystals of Li5[Co(LH–5)2]Cl · 8 H2O ( 1 ) (L = Xylitol) are obtained from cobalt(II) and xylitol in alkaline aqueous solution by oxidation with air. In the homoleptic binuclear dicobaltate(iii) ions, the O10 set of an edge-shared Co2O10 dioctahedron is provided by two entirely deprotonated xylitol ligands.  相似文献   

15.
Lithium Salts of Tris(trimethylsilylamino)silane - Their Structures in Solution and in the Solid State* Amides, which result from the reaction of tris(trimethylsilylamino)silane (Me3SiNH)3SiH ( 1 ) with n-butyllithium in the molar ratio 1:1 and 1:2 in nonpolar solvents, form a system in which the aminosilane 1 , the monoamide (Me3SiNLi)(Me3SiNH)2SiH ( 2a ), the diamide (Me3SiNLi)2(Me3SiNH)SiH ( 3 ), and the triamide (Me3SiNLi)3SiH ( 4 ) are in equilibrium. When the monoamide 2a is dissolved in THF only the dimeric monolithiated THF adduct 2b is obtained. An X-ray structure analysis of the lithium silylamide 2b reveals that in the dimeric unit one of the lithium atoms is coordinated by THF, the two lithium atoms thus differing in coordination number (3 versus 4). An X-ray study of the triamide 4 reveals a centrosymmetric polycycle. Multipole interactions are formed between the lithium and the nitrogen atoms. The reaction of the diamide 3 with chlorotrimethylsilane in boiling THF yields the cis isomer of the cyclic diamide [(Me3SiNLi)(Me3SiNH)SiN(SiMe3)]2· 2 THF ( 5 ) as a byproduct. According to an X-ray structure analysis of 5 the lithium centers are coordinated by one oxygen and three nitrogen atoms, which form a strongly distorted tetrahedron. The interactions between lithium and nitrogen atoms N(1) and N(2), which are part of the four-membered Si2N2 cycle, have to be considered as weak on the basis of the remarkably long Li-N distances (233 and 243 pm).  相似文献   

16.
Synthesis and Structure of MII[AuF4]2 (MII ? Cd, Hg) Cd[AuF4]2 and the isotypic compound Hg[AuF4]2, both are yellow, crystallize tetragonal in the space-group P4/mcc-D (No. 124) with a = 575.0/575.6 pm, c = 1034.8/1042.3 pm and Z = 2. The single-crystals were obtained by solid-state reactions in goldtubes.  相似文献   

17.
Preparation and Crystal Structure of Tetraphenylphosphonium Hexathiocyanatorhodate(III), [P(C6H5)4]3[Rh(SCN)6] By treatment of RhCl3 · n H2O with KSCN in water a mixture of the linkage isomers [Rh(NCS)n(SCN)6–n]3?, n = 0–2 is formed which is separated by ion exchange chromatography on diethylaminoethyl cellulose. The X-ray structure determination on a single crystal of [P(C6H5)4]3[Rh(SCN)6] (monoclinic, space group C1c1, a = 13.620(5), b = 22.929(13), c = 22.899(9) Å, β = 98.55(3)°, Z = 4) confirms the coordination of all ligands via S with the middle Rh? S distance of 2.372 Å and Rh? S? C angles of 109°. The SCN groups are nearly linear with 175° and averaged bondlengths S? C 1.63 and C? N 1.14 Å. The crystal lattice is build up by layers of complex anions and voluminous cations with no specific interactions but which are closely connected by thiocyanate ligands and phenyl rings.  相似文献   

18.
《Electroanalysis》2004,16(18):1528-1535
In the proposed method As(III) is determined with a wall‐jet flow cell by means of potentiostatic co‐deposition of Au(III) and As(III) at a glassy‐carbon electrode and subsequent chemical stripping with Au(III). Factors affecting sensitivity and precision including acidity, Au(III) concentration, electrodeposition potential and flow rate were optimized. Optimum determination of As(III) in solutions containing 160 mg L?1 and 1.2 M hydrochloric acid was accomplished with an electrolysis potential of ?0.1 V (vs. Ag/AgCl) and a flow rate of 0.59 mL min?1. Different linear concentration ranges were achieved under these conditions with good precision and relative standard deviations between 6–9%. The detection limit obtained after 120 s of electrolysis was 0.55 μg L?1.  相似文献   

19.
Preparation, Characterization, and Crystal Structures of Tetraiodoferrates(III) The extremely air and moisture sensitive tetraiodoferrates MFeI4 with M = K, Rb and Cs have been synthesized by reaction of Fe, MI and I2 at 300°C in closed quartz ampoules. The essentially more stable alkylammonium tetraiodoferrates NR4FeI4 with R = H, C2H5, n-C3H7, n-C4H9 and n-C5H11 can be obtained by reaction of Fe, NR4I and I2 in nitromethane. The Raman and UV/Vis-spectra of the black compounds show the existence of tetrahedral [FeI4]? ions in the structures. The crystal structure of the monoclinic CsFeI4 (CsTlI4 type, spgr P21/c; a = 7.281(1) Å; b = 17.960(3) Å; c = 8.248(2) Å; β = 107.35(15)°) is built up by tetrahedral [FeI4]? ions and CsI11 polyhedra. The crystal structure of the orthorhombic (n-C5H11)4NFeI4 (spgr Pnna; a = 20.143(4) Å; b = 12.683(3) Å; c = 12.577(3) Å) contains tetrahedral [(n-C5H11)4N]+ ions and [FeI4]? ions, respectively.  相似文献   

20.
Preparation and Crystal Structure of (n-Bu4N)3[Ir(NCS)(SCN)5] The evaporated ethanolic extrakt of the reaction product of K3[IrCl6] and HNO3, refluxed with an aqueous KSCN solution yields a mixture of the linkage isomers [Ir(NCS)n(SCN)6?-n]3?, n = 0? 2, and small amounts of linkage isomeric chloropentarhodanoiridates(III), from which [Ir(NCS)(SCN)5]3? has been isolated by ion exchange chromatography on DEAE-cellulose. The X-Ray structure determination on a single crystal of (n-Bu4N)3[Ir(NCS)(SCN)5] (monoclinic, space group P 21/a, a = 17.513(5), b = 32.607(5), c = 23.661(5) Å, β = 94.757(5)°, Z = 8) confirms the existance of a heteroleptic hexakis(thiocyanato(N)-thiocyanato(S))iridate(III) with an Ir? N distance of 2.03 Å and Ir? S bond lengths between 2.29 and 2.38 Å. The SCN groups with angles between 166 and 175° are nearly linear with Ir? S? C angles from 99.9 to 109.4°. The Ir? N? C angles of the two crystallographic independent anions are 166 and 174°.  相似文献   

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