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1.
The metal‐directed self‐assembly of biphenylantimony trichloride and homocarboxylic acids LH [L = 2‐CHO‐C6H4COO ( 1 ), 2, 3‐2F‐C6H4COO ( 2 ), 4‐CF3–C6H4COO ( 3 )] provided three novel tetranuclear organoantimony(V) complexes, which were characterized by elemental analysis, FT‐IR, 1H, and 13C NMR spectroscopy as well as melting point, and X‐ray single crystal analysis. In the molecular structure, four hexacoordinate antimony atoms are linked into a [Sb2(μ‐O)2]2(μ‐O)2 “cage” architecture by oxo‐bridges which are terminally bridged by two carboxyl groups.  相似文献   

2.
Powder material of ?‐Fe2O3 was obtained by thermal decomposition of the clay mineral nontronite and subsequent isolation of the ferric oxide by leaching the silicate phases. Additionally, crystals of ?‐Fe2O3 were grown as precipitates by internal oxidation of a Pd96Fe4 alloy. Analysis of the precipitate crystals by electron diffraction yields an orthorhombic crystal system and space group Pna21 ab initio. X‐ray diffraction data of the powder containing small amounts of Al substituting Fe were refined by the Rietveld method. The refinement yields lattice parameters a = 507.15 pm, b = 873.59 pm and c = 941.78 pm, and atom positions. ?‐Fe2O3 is isostructural with κ‐Al2O3, AlFeO3, and GaFeO3 having an anion stacking sequence /ABAC/, and 1/4 of the cations in tetrahedral co‐ordination. Some strongly distorted FeO6 octahedrons with one large Fe‐O distance, which may be considered as a 5+1 co‐ordination, appear to be characteristic for ?‐Fe2O3. The structure shows elements known from silicates and oxyhydroxides of iron, respectively.  相似文献   

3.
The synthesis and single crystal X‐ray structure determination are reported for the 2,2′ : 6′,2″‐terpyridine (= tpy) adduct of bismuth(III) nitrate. The hydroxide‐bridged dimer [(η2‐NO3)2(tpy)Bi(μ‐OH)2Bi(tpy)(η2‐NO3)2] with nine‐coordinate geometry about Bi was the only isolable product from all crystallization attempts in varying ratios of Bi(NO3) : terpy.; [(η2‐NO3)2(tpy)Bi(μ‐OH)2Bi(tpy) · (η2‐NO3)2] is triclinic, P 1, a = 7.941(8), b = 10.732(9), c = 11.235(9) Å; α = 63.05(1), β = 85.01(1), γ = 79.26(1)°, Z = 1, dimer, R = 0.058 for N0 = 2319.  相似文献   

4.
A new (β‐)modification of the mercury molybdate Hg2Mo2O7, thermodynamically stable at temperatures above 390 ± 10 °C, was prepared by solid state reaction of HgO with MoO2 in sealed silica tubes. Its crystal structure, determined from single‐crystal X‐ray data, has a very pronounced subcell: space group P2/c, a = 600.9(1) pm, b = 388.7(1) pm, c = 1428.4(2) pm, β = 105.88(1)°, Z = 2, R = 0.052 for 797 structure factors and 52 variable parameters. In the superstructure of this high‐temperature β‐modification the a and the b axes of the subcell are doubled: C2/c, a = 1201.9(2) pm, b = 777.3(1) pm, c = 1428.4(2) pm, β = 105.88(1)°, Z = 8, R = 0.040 for 1490 F values and 110 variables. Like the previously reported low‐temperature α‐modification, the β‐modification consists of two‐dimensionally infinite sheets of edge‐ and corner‐sharing MoO6 octahedra. These sheets are linked by Hg2 pairs. Thus, the structures of the two modifications (α and β) differ essentially only in the orientation of the Hg2 pairs, which are located between the sheets of the MoO6 octahedra. The superstructure of the β‐modification differs from the subcell‐structure by the puckering of the sheets of MoO6 octahedra. A hypothetical displacive phase transition between the subcell‐structure (corresponding to the potential high‐temperature structure) and the superstructure of β‐Hg2Mo2O7 is discussed.  相似文献   

5.
Potassium Heptachlorodioxodimolybdate(V), KMo2O2Cl7 KMo2O2Cl7 was obtained at 400 °C from the reaction of SCl2 with molybdenum which contained traces of potassium. Its crystal structure is monoclinic, space group C2/c, a = 1094.1, b = 1139.1, c = 1018.0 pm, β = 110.16°, Z = 4. In the Mo2O2Cl7 ion two coordination octahedra share a common face with three chlorine atoms. The crystal structure can be derived from the CsNiCl3 type by vacating one third of the Ni and two thirds of the Cs positions. The crystallographic group-subgroup relationship is given.  相似文献   

6.
The barium perfluoroalkanedisulfonates Ba(O3S)2(CF2)n (n = 1, 3–5) and the new potassium fluoroalkanedisulfonates K2(O3S)2CHF, K2(O3S)2CF2, and K2(O3S)2(CF2)5 have been prepared by reaction of (CF2)n(SO2F)2 (n = 1, 3–5) or CHF(SO2F)2 with CaO (or Ca(OH)2) and M(OH)x (M = Ba, x = 2; M = K, x = 1) or with Ba(OH)2 alone (n = 1) in water. In each of the crystal structures of K2(O3S)2CHF and K2(O3S)2CF2, there is an eight‐coordinate and a six‐coordinate potassium ion, whilst in K2(O3S)2(CF2)3H2O, two different eight‐coordinate potassium ions are linked by a bridging water molecule. One potassium has additionally six sulfonate oxygen and one fluorine donor atoms, and the other, five sulfonate oxygens and two fluorine donor atoms. The preparation of highly crystalline [Nien3][(O3S)(CF2)n] (en = ethane‐1,2‐diamine; n = 1, 3–5) and the X‐ray crystal structures for n = 1 or 3 provide evidence for the value of perfluoroalkanedisulfonate ions as counter ions for the crystallization of cationic complexes.  相似文献   

7.
N,N‐bis(carboxymethyl)‐1‐adamantylamine acid (H2BCAA) or N‐(1‐adamantyl)‐iminodiacetic acid forms zwitterions that are intra‐stabilized by a ‘bifurcated’ N+‐H···O(carboxyl)2 interaction. In the crystal, both half‐protonated carboxyl groups of H2BCAA± are involved in linear O‐H···O inter‐molecular bridges of 2.46Å. In the studied BCAA‐CuII derivatives, the iminodiacetate‐moiety of the BCAA chelating ligand exhibits a mer‐NO2 conformation in [Cu(BCAA)(H2O)2] ( 1 ) and [Cu(BCAA)(Him)]2 ( 2 ), but a fac‐O2+N(apical) conformation in [Cu(BCAA)(bpy)(H2O)]·3.5H2O ( 3 ) [Him = imidazole, bpy =2,2′‐bipyridine]. In clear contrast, dipyridylamine (dpya), as auxiliary ligand, seems to be unable to promote the fac‐O2+N(apical) conformation in BCAA, as reveal the structures of two new salts with the trinuclear cation [(dpya)2Cu‐μ2‐Cu(BCAA)2‐Cu(dpya)2]2+ and the anions [Cu(BCAA)2]2? ( 4 ) or NO3? ( 5 ), respectively.  相似文献   

8.
[{C8H12Rh}33‐OH)2]SbF6: A New Organometallic Rhodium Complex with Rh3O2 Core Crystals of C24H38F7O2Rh3Sb ( 3 ) obtained from the crystallisation of 2 from wet solvents consist of [{C8H12Rh}33‐OH)2]+ cations connected with the SbF6 anions via hydrogen bonds. In the cations, the Rh3 faces are bicapped by OH ligands.  相似文献   

9.
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   

10.
Pale yellow single crystals of [O=C(NPPh3)C(I)=C(NPPh3)‐C(NPPh3)2]+I·1.5 thf ( 1 ·1.5 thf) have been obtained by the reaction of INPPh3 with thallium in thf suspension. They are characterized by IR spectroscopy and by a crystal structure determination. 1 ·1.5 thf crystallizes in the monoclinic space group P21/n, Z = 4, lattice dimensions at ‐83?C: a = 1101.7(1), b = 3449.0(2), c = 2000.4(1) pm, β = 104.88(1)?, R1 = 0.0382. 1 can be understood as a cationic variation of (Z)‐2‐butenale in which all H atoms are substituted by triphenylphosphoraneimine residues and by a iodine atom, respectively.  相似文献   

11.
In situ Investigation of the Reaction of Ammonium Monomolybdate (NH4)2MoO4 with Ammonia: The Structure of (NH4)2[Mo3O10] The reactivity of both polymorphs of (NH4)2MoO4 with ammonia was investigated in a temperature range between 20 and 180 °C. Time and temperature controlled X‐ray powder diffraction as well as thermogravimetrical and differential thermal analysis were used to investigate this reaction.The formation of (NH4)2[Mo3O10] from (NH4)2MoO4 is reversible in a humid and irreversible in a dry NH3 gas flow. Heating (NH4)2MoO4(mP60) under an atmosphere of humid NH3 at about 170 °C forms (NH4)2[Mo3O10] and succesively cooling yields the (NH4)2MoO4(mS60) polymorph. (NH4)2[Mo3O10] crystallises isostructural to the potassium compound with space group C2/c (No. 15) and lattice constants a = 1398.2(4), b = 804.1(2), b = 921.0(3) pm and β = 98.833(4)°.  相似文献   

12.
13.
[Ph2P(O)CH2Im][F3B(μ‐OH)BF3]. First Structural Characterization of the Hexafluoro(μ‐hydroxo)diborate Ion [1] The hexafluoro(μ‐hydroxo)diborate ion has been isolated as it's Ph2P(O)CH2Im salt [Im = 2‐(1, 3, 4, 5‐tetramethylimidazolio)] ( 2 ) through basic hydrolysis of [Ph2P(OBF3)CH2Im]BF4 ( 1 ). The crystal structure of 2 · CH2Cl2 reveals the presence of ion pairs linked by unsymmetrical O‐H‐O hydrogen bonds.  相似文献   

14.
Synthesis and Crystal Structure of Terbium(III) meta‐Oxoborate Tb(BO2)3 (≡ TbB3O6) The terbium meta‐oxoborate Tb(BO2)3 (≡ TbB3O6) is obtained as single crystals by the reaction of terbium, Tb4O7 and TbCl3 with an excess of B2O3 in gastight sealed platinum ampoules at 950 °C after three weeks. The compound appears to be air‐ and water‐resistant and crystallizes as long, thin, colourless needles which tend to growth‐twinning due to their marked fibrous habit. The crystal structure of Tb(BO2)3 (orthorhombic, Pnma; a = 1598.97(9), b = 741.39(4), c = 1229.58(7) pm; Z = 16) contains strongly corrugated oxoborate layers {(BO2)} built of vertex‐linked [BO4]5‐ tetrahedra (d(B‐O) = 143 ‐ 154 pm, ?(O‐B‐O) = 102‐115°) which spread out parallel (100). The four crystallographically different Tb3+ cations all exhibit coordination numbers of eight towards the oxygen atoms (d(Tb‐O) = 228‐287 pm). The corresponding metal cation polyhedra [TbO8]13+ too convene to layers (composition: {(Tb2O11)16‐}) which are likewise oriented parallel to the (100) plane.  相似文献   

15.
Single crystals of α‐ and β‐Mg2[(UO2)3(SeO4)5](H2O)16 have been synthesized by evaporation from an aqueous solution of the ionic components. The structure of α‐Mg2[(UO2)3(SeO4)5](H2O)16 (monoclinic, C2/c, a = 19.544(3), b = 10.4783(11), c = 18.020(3) Å, β = 91.352(12)°, V = 3689.3(9) Å3) has been solved by direct methods and refined to R1 = 0.048 on the basis of 4338 unique observed reflections. The structure of β‐Mg2[(UO2)3(SeO4)5](H2O)16 (orthorhombic, Pbcm, a = 10.3807(7), b = 22.2341(19), c = 33.739(5) Å, V = 7787.2(14) Å3) has been solved by direct methods and refined to R1 = 0.107 on the basis of 3621 unique observed reflections. The structures of α‐ and β‐Mg2[(UO2)3(SeO4)5](H2O)16 are based upon sheets with the chemical composition [(UO2)3(SeO4)5]4‐. The sheets are formed by corner sharing between pentagonal bipyramids [UO7]8‐ and SeO42‐ tetrahedra. In the α‐modification, the [(UO2)3(SeO4)5]4‐ sheets are more or less planar and run parallel to (001). In the structure of the β‐modification, the uranyl selenate sheets are strongly corrugated and oriented parallel to (010). The [Mg(H2O)6]2+ polyhedra reside in the interlayers and provide three‐dimensional linkage of the uranyl selenate sheets via hydrogen bonding. In addition to H2O groups attached to Mg2+ cations, both structures also contain H2O molecules that are not bonded to any cation. The [(UO2)3(SeO4)5]4‐ sheets in the structures of α‐ and β‐Mg2[(UO2)3(SeO4)5](H2O)16 represent two different structural isomers. The sequences of the orientations of the tetrahedra within the sheets can be described by their orientational matrices with their shortened forms ( ddudd □ /uu □ uud ) and ( dd □ dd □ uu □ uu □ /uuduumdduddm ) for α‐ and β‐Mg2[(UO2)3(SeO4)5](H2O)16, respectively. A short review on the isomerism of [(UO2)3(TO4)5]4‐ sheets (T = S, Cr, Se, Mo) is given.  相似文献   

16.
Synthesis and Crystal Structures of α‐, β‐Ba3(PS4)2 and Ba3(PSe4)2 Ba3(PS4)2 and Ba3(PSe4)2 were prepared by heating mixtures of the elements at 800 °C for 25 h. Both compounds were investigated by single crystal X‐ray methods. The thiophosphate is dimorphic and undergoes a displacive phase transition at about 75 °C. Both modifications crystallize in new structure types. In the room temperature phase (α‐Ba3(PS4)2: P21/a; a = 11.649(3), b = 6.610(1), c = 17.299(2) Å, β = 90.26(3)°; Z = 4) three crystallographically independent Ba atoms are surrounded by ten sulfur atoms forming distorted polyhedra. The arrangement of the PS4 tetrahedra, isolated from each other, is comparable with the formation of the SO42? ions of β‐K2SO4. In β‐Ba3(PS4)2 (C2/m; a = 11.597(2), b = 6.727(1), c = 8.704(2) Å; β = 90.00(3)°; Z = 2) the PS4 tetrahedra are no more tilted along [001], but oriented parallel to each other inducing less distorted tetrahedra and polyhedra around the Ba atoms, respectively. Ba3(PSe4)2 (P21/a; a = 12.282(2), b = 6.906(1), c = 18.061(4) Å; β = 90.23(3)°; Z = 4) is isotypic to α‐Ba3(PS4)2 and no phase transition could be detected up to about 550 °C.  相似文献   

17.
The reaction of ammonium heptamolybdate with hydrazine sulfate in an aqueous solution of glycine at room temperature yielded colorless crystals of (NH4)4[(NH3CH2CO)2(Mo8O28)] · 2 H2O. The crystal is monoclinic, space group C2/c (no. 15), a = 17.234 Å, b = 10.6892 Å, c = 18.598 Å, β = 108.280°, V = 3253.2 Å3, Z = 4. The crystal structure contains ammonium cations and isolated octamolybdate(4–) anions, [(NH3CH2CO)2(Mo8O28)]4–, with two zwitterionic glycine molecules as ligands.  相似文献   

18.
The synthesis and molecular structure of trans‐{bis[(acetato‐κO)‐(2‐(1‐aziridinyl)ethanol‐κ2N,O)]}cobalt(II) ( 4 ) and cis‐{bis[chlorido‐(2‐(1‐aziridinyl)ethanol‐κ2N,O)]}cobalt(II) ( 5 ) is reported. Both neutral chelate complexes are prepared from the corresponding CoII salt [CoX2; X = OAc ( 1 ), Cl ( 2 )] and 2‐(1‐aziridinyl)ethanol (azolH, 3 ) in dry dichloromethane. A third, ionic complex, cis‐{bis[aqua‐(2‐(1‐aziridinyl)ethanol‐κ2N,O)]}cobalt(II) diacetate ( 6 ) is formed from 4 in the presence of water and could be crystallized from aqueous dichloromethane. In all cases, 2‐(1‐aziridinyl)ethanol is coordinating as bidentate chelate ligand by the nitrogen and oxygen atom of the aziridinyl and hydroxy moiety. After purification, the compounds have been fully characterized using IR spectroscopy and FAB+‐MS. The single‐crystal X‐ray structure analysis revealed a distorted octahedral geometry for all complexes with either trans ( 4 ) or cis ( 5 , 6 ) configuration.  相似文献   

19.
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   

20.
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   

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