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1.
By replacing Mn in YCa3(MnO)3(BO3)4 with trivalent Al and Ga, two new borates with the compositions of YCa3(MO)3(BO3)4 (M=Al, Ga) were prepared by solid-state reaction. Structure refinements from X-ray powder diffraction data revealed that both of them are isostructural to gaudefroyite with a hexagonal space group P63/m. Cell parameters of a=10.38775(13)Å, c=5.69198(10)Å for the Al-containing compound and a=10.5167(3)Å, c=5.8146(2)Å for the Ga analog were obtained from the refinements. The structure is constituted of AlO6 or GaO6 octahedral chains interconnected by BO3 groups in the ab plane to form a Kagomé-type lattice, leaving trigonal and apatite-like tunnels. It is found that most rare-earth and Cr, Mn ions can be substituted into the Y3+ and M3+ sites, respectively, and the preference of rare-earth ions to locate in the trigonal tunnel is correlated to the sizes of the M3+ ions.  相似文献   

2.
A new ruthenium-rhodium mixed-metal cluster HRuRh3(CO)12 and its derivatives HRuRh3(CO)10(PPh3)2 and HRuCo3(CO)10(PPh3)2 have been synthesized and characterized. The following crystal and molecular structures are reported: HRuRh3(CO)12: monoclinic, space group P21/c, a 9.230(4), b 11.790(5), c 17.124(9) Å, β 91.29(4)°, Z = 4; HRuRh3(CO)10(PPh3)2·C6H14: triclinic, space group P1, a 11.777(2), b 14.079(2), c 17.010(2) Å, α 86.99(1), β 76.91(1), γ 72.49(1)°, Z = 2; HRuCo3(CO)10(PPh3)2·CH2Cl2: triclinic, space group P1, a 11.577(7), b 13.729(7), c 16.777(10) Å, α 81.39(4), β 77.84(5), γ 65.56°, Z = 2. The reaction between Rh(CO)4? and (Ru(CO)3Cl2)2 tetrahydrofuran followed by acid treatment yields HRuRh3(CO)12 in high yield. Its structural analysis was complicated by a 80–20% packing disorder. More detailed structural data were obtained from the fully ordered structure of HRuRh3(CO)10(PPh3)2, which is closely related to HRuCo3(CO)10(PPh3)2 and HFeCo3(CO)10(PPh3)2. The phosphines are axially coordinated.  相似文献   

3.
Thermal degradation of the cluster compound Os3(CO)8(PPh2H)(μ3-S)2 (I) at 125°C leads to decarbonylation and formation of the new ligand bridged hexanuclear cluster Os6(CO)14(μ-PPh2)23-S)34-S) (II) in 11% yield. Space Group: P1, No. 2, a 10.427(5), b 13.552(3), c 17.919(3) Å, α 84.87(2), β 75.41(3), γ 78.43(3)°, V 2399(2) Å3Z = 2, ?calc 2.82 g cm?3. The structure was solved by the heavy atom method and refined (3223 reflections) to the final residuals R = 0.042 and Rw = 0.036. The molecule consists of two sulfido bridged open triosmium clusters which are linked by a bridging sulfido ligand and a bridging diphenylphosphino ligand.  相似文献   

4.
5.
New uranyl vanadates A3(UO2)7(VO4)5O (M=Li (1), Na (2), Ag (3)) have been synthesized by solid-state reaction and their structures determined from single-crystal X-ray diffraction data for 1 and 3. The tetragonal structure results of an alternation of two types of sheets denoted S for 2[UO2(VO4)2]4− and D for 2[(UO2)2(VO4)3]5− built from UO6 square bipyramids and connected through VO4 tetrahedra to 1[U(3)O5-U(4)O5]8− infinite chains of edge-shared U(3)O7 and U(4)O7 pentagonal bipyramids alternatively parallel to a- and b-axis to construct a three-dimensional uranyl vanadate arrangement. It is noticeable that similar [UO5]4− chains are connected only by S-type sheets in A2(UO2)3(VO4)2O and by D-type sheets in A(UO2)4(VO4)3, thus A3(UO2)7(VO4)5O appears as an intergrowth structure between the two previously reported series. The mobility of the monovalent ion in the mutually perpendicular channels created in the three-dimensional arrangement is correlated to the occupation rate of the sites and by the geometry of the different sites occupied by either Na, Ag or Li. Crystallographic data: 293 K, Bruker X8-APEX2 X-ray diffractometer equipped with a 4 K CCD detector, MoKα, λ=0.71073 Å, tetragonal symmetry, space group Pm2, Z=1, full-matrix least-squares refinement on the basis of F2; 1,a=7.2794(9) Å, c=14.514(4) Å, R1=0.021 and wR2=0.048 for 62 parameters with 782 independent reflections with I?2σ(I); 3, a=7.2373(3) Å, c=14.7973(15) Å, R1=0.041 and wR2=0.085 for 60 parameters with 1066 independent reflections with I?2σ(I).  相似文献   

6.
A new layered vanadium oxide [H3N(CH2)4NH3](V6O14) was synthesized hydrothermally under autogenous pressure at 180°C for 48 h from a mixture of H2N(CH2)4NH2 and V2O5 in aqueous solution. Its structure was determined from single-crystal X-ray diffraction at room temperature with final R=0.0774 and Rw=0.0893. It crystallizes in the monoclinic system (space group P21/n with a=9.74(2) Å, b=6.776(5) Å, c=12.60(2) Å, β=96.1(1)°, V=827(2) Å3 and Z=2). This compound contains mixed-valence V5+/V4+ vanadium oxide layers built from [VVO4] tetrahedra and pairs of edge-sharing [VIVO5] square pyramids with protonated organic amines occupying the interlayer space.  相似文献   

7.
Reaction of the complexes Ru(CO)2Cl2L [L = 2,2′-bipyridyl (bpy) or 1,10-phenanthroline (phen)] with trifluoromethanesulphonic acid under carefully controlled conditions yields Ru[cis-(CO)2] [cis-(O3SCF3)2] (bidentate complexes. From reactions of the trifluoromethanesulphonates with the appropriate bidentate ligands, the new complexes [cis-Ru(CO)2-L(L′)]2+ (L as above; L′ = 4,4′-dimethyl-2,2′-bipyridyl or 4,4′-diisopropyl-2,2′-bipyridyl) as well as the known [cis-Ru(CO)2L2]2+ and [cis-Ru(CO)2bpy(phen)]2+ have been prepared.  相似文献   

8.
Dark brown single crystals of [Ag(NH3)2]Ag(OsO3N)2 were obtained from the reaction of Ag2CO3, OsO4, and NH3 in aqueous solution. The crystal structure was solved in the monoclinic space group C2/m, with the following unit-cell dimensions: a=1962.5(3), b=633.1(1), c=812.6(1) pm, β=96.71(1)°. The final reliability factor was R=0.0256 for 1034 reflections with I>2σ(I). Linear [Ag(NH3)2]+ ions are present oriented perpendicular to the [010] direction, leading to short Ag+-Ag+ distances of 316 pm. A second type of Ag+ ions in the crystal structure present coordination number “6+1” and are surrounded by oxygen and nitrogen atoms of the nitridoosmate groups. Within the first of the two crystallographically distinguishable anions one can clearly differentiate between oxygen and nitrogen atoms while the second one exhibits a N/O disorder over two positions. The infrared spectrum of [Ag(NH3)2]Ag(OsO3N)2 shows the typical absorptions which can be attributed to the complex anions and the NH3 ligands.  相似文献   

9.
The two new compounds, Sr4Cu3(AsO4)2(AsO3OH)4·3H2O (1) and Ba2Cu4(AsO4)2(AsO3OH)3(2), were synthesized under hydrothermal conditions. They represent previously unknown structure types and are the first compounds synthesized in the systems SrO/BaO-CuO-As2O5-H2O. Their crystal structures were determined by single-crystal X-ray diffraction [space group C2/c, a=18.536(4) Å, b=5.179(1) Å, c=24.898(5) Å, β=93.67(3)°, V=2344.0(8) Å3, Z=4 for 1; space group P42/n, a=7.775(1) Å, c=13.698(3) Å, V=828.1(2) Å3, Z=2 for 2]. The crystal structure of 1 is related to a group of compounds formed by Cu2+-(XO4)3− layers (X=P5+, As5+) linked by M cations (M=alkali, alkaline earth, Pb2+, or Ag+) and partly by hydrogen bonds. In 1, worth mentioning is the very short hydrogen bond length, D···A=2.477(3) Å. It is one of the examples of extremely short hydrogen bonds, where the donor and acceptor are crystallographically different. Compound 2 represents a layered structure consisting of Cu2O8 centrosymmetric dimers crosslinked by As1φ4 tetrahedra, where φ is O or OH, which are interconnected by Ba, As2 and hydrogen bonds to form a three-dimensional network. The layers are formed by Cu2O8 centrosymmetric dimers of CuO5 edge-sharing polyhedra, crosslinked by As1O4 tetrahedra. Vibrational spectra (FTIR and Raman) of both compounds are described. The spectroscopic manifestation of the very short hydrogen bond in 1, and ABC-like spectra in 2 were discussed.  相似文献   

10.
The selective in situ synthesis of trans and cis(CH3CN)-[Ru(bpy)(CO)2 (CH3CN)2]2+ isomers from the same [Ru(CO)2 (CH3CN)3]22+ dimer precursor but using either an electrochemical-chemical or chemical-electrochemical process is described.  相似文献   

11.
Crystals of two new layered BaNaSc(BO3)2 (I) and BaNaY(BO3)2 (II) orthoborates are grown from the melt-solution by the spontaneous crystallization onto the platinum loop. Single crystal X-ray analysis showed that the compounds are isostructural with the space group R3¯, a=5.23944(12) and 5.3338(2) Å, and c=34.5919(11) and 35.8303(19) Å for I and II, respectively, Z=6. The distinctive feature of the structure is the close-packed composite anion-cation (Ba,Na)(BO3) layers. The layers are combined into the base building packages of two types: {M3+[Ba2+(BO3)3−]2}+ and {M3+[Na+(BO3)3−]2}, where M is Sc or Y. Neutral-charge two-package (four-layer) blocks are stacked by the rhombohedral principle into twelve layers of the cubic packing.  相似文献   

12.
The rate of the reaction
has been investigated at 40–65°C with [HClO4] varying from 0.04 to 0.6 M (μ = 0.6 M, NaClO4). The observed rate law has the form: -d[Cr(NH3)5(NCO)2+]/dt = kobs[Cr(NH3)5(NCO)2+] where kobs = a[H+]2{1 + b[H+]2} and ?1 at 55.0°C, a = 0.36 M?1 s?2 and b = 6.9 × 10?3 M?1 s?1. The rate of loss of Cr(NH3)5(NCO)2+ increases with increasing acidity to a limiting value (at [H+] ~ 0.5 M) but the yield of Cr(NH3)63+ decreases with increasing [H+] and increases with increasing temperature. In the kinetic studies the maximum yield of Cr(NH3)63+ was 35% but a synthetic procedure has been developed to give a 60% yield.  相似文献   

13.
The new complex Ru3(CO)9(PPh2H)3 (I) was prepared by the direct thermal reaction of Ru3(CO)12 with PPh2 H and was spectroscopically characterized. Irradiation of I with λ ≥ 300 nm leads to the formation of Ru2(μ-PPh2)2(CO)6 (II) and three new phosphido-bridged complexes, Ru3(μ-H)2(μ-PPh2)2(CO)8 (III), Ru3(μ-H)2(μ-PPh2)2(CO)7(PPh2H) (IV) and Ru3(μ-H)(μ-PPh2)3(CO)7 (V). These complexes have been characterized spectroscopically and Ru3 (μ-H)(μ-PPh2)3(CO)7 by a complete single crystal X-ray structure determination. It crystallizes in the space group P21/n with a 20.256(3), b 22.418(6), c 20.433(5) Å, β 112.64(2)°, V 8564(4) Å3, and Z = 8. Diffraction data were collected on a Syntex P21 automated diffractometer using graphite-monochromatized Mo-Kα radiation, and the structure was refined to RF 4.76% and RwF 5.25% for the 8,847 independent reflections with F0 > 6σ(F0). The structure consists of a triangular array of Ru atoms with seven terminal carbonyl ligands, three bridging diphenylphosphido ligands which bridge each of the RuRu bonds, and the hydride ligand which bridges one RuRu bond. Complex IV was also shown to give V upon photolysis and is thus an intermediate in the photoinduced formation of V from I.  相似文献   

14.
The ion-solvent interaction of Sr(NO3)2 and Cd(NO3)2 in 10, 20 and 30 wt.% organic solvent (dioxane, glycol, methyl alcohol)-water mixtures at different temperatures has been studied using electrolytic conductivity data. The dissociation constant of the ion-pair Sr(NO3)+ and Cd(NO3)+ has been calculated along with ΔG0t, ΔG0t(cl) and ΔG0t(ch). The ion pairs interact with the solvents and the interaction is of the order dioxane+water>methyl alcohol+water>glycol+water.  相似文献   

15.
The objective of the present work was to synthesize mononuclear ruthenium complex [RuCl2(CO)2{Te(CH2SiMe3)2}2] (1) by the reaction of Te(CH2SiMe3)2 and [RuCl2(CO)3]2. However, the stoichiometric reaction affords a mixture of 1 and [RuCl2(CO){Te(CH2SiMe3)2}3] (2). The X-ray structures show the formation of the cis(Cl), cis(C), trans(Te) isomer of 1 and the cis(Cl), mer(Te) isomer of 2. The 125Te NMR spectra of the complexes are reported. The complex distribution depends on the initial molar ratio of the reactants. With an excess of [RuCl2(CO)3]2 only 1 is formed. In addition to the stoichiometric reaction, a mixture of 1 and 2 is observed even when using an excess of Te(CH2SiMe3)2. Complex 1 is, however, always the main product. In these cases the 125Te NMR spectra of the reaction solution also indicates the presence of unreacted ligand.  相似文献   

16.
A re-interpretation and re-evaluation of single-crystal X-ray diffraction data of a previously reported ‘(NH4)2(NH3)[Ni(NH3)2Cl4]’ (J. Solid State Chem. 162 (2001) 254) give a new formula (NH4)2−2z[Ni(NH3)2]z[Ni(NH3)2Cl4] with z=0.152. This new formula results from defects in an idealized ‘(NH4)2[Ni(NH3)2Cl4]’ basic structure, where two adjacent NH4+ cations are replaced by one Ni(NH3)22+ unit. Cl anions from the basic structure complete the coordination sphere of the new Ni2+ to [Ni(NH3)2Cl4]2−.  相似文献   

17.
Cerium(III) diammonium polyphosphate, (NH4)2Ce(PO3)5, is triclinic P1 with the following unit cell dimensions: a = 7.241(5) Å, b = 13.314(8) Å, c = 7.241(5)Å, α = 90.35(5)°, β′ = 107.50(5)°, γ = 90.28(5)°, and Z = 2, V = 665.7 Å3, Dx = 2.85 g/cm3. The crystal structure of this new type of polyphosphate has been solved and refined from 4130 independent reflections to a final R value 0.029. The most interesting feature of this salt is the existence of two infinite crystallographically nonequivalent (PO3)? chains, one running parallel to the a axis, the other along the c axis, both with a period of five tetrahedra. This compound seems to be the first example of a long chain polyphosphate with crystallographic independent chains.  相似文献   

18.
A high-yield synthesis of trans-RuCl2(CS)(H2O)(PPh3)2 from RuCl2(PPh3)3 and CS2 is described. The coordinated water molecule is labile, and introduction of CNR (R  p-toyl or p-chlorophenyl) leads to yellow trans-RuCl2(CS)(CNR)(PPh3)2, which isomerises thermally to colourless cis-RuCl2(CS)(CNR)(PPh3)2. Reaction of AgClO4 with cis-RuCl2(CS)(CNR)(PPh3)2 gives [RuCl(CS)(CNR)(H2O)(PPh3)2]+, from which [RuCl(CS)(CO)(CNR)(PPh3)2]+ and [RuCl(CS)(CNR)2(PPh3)2]+ are derived. Reaction of trans-RuCl2(CS)(H2O)(PPh3)2 with sodium formate gives Ru(η2-O2CH)Cl(CS)(PPh3)2, which undergoes decarboxylation in the presence of (PPh3) to give RuHCl(CS)(PPh3)3. Ru(η2-O2CH)H(CS)(PPh3)2 and Ru(η2-O2CMe)-H(CS)(PPh3)2 are also described.  相似文献   

19.
Two new thallium iodates have been synthesized, Tl(IO3)3 and Tl4(IO3)6 [Tl+3Tl3+(IO3)6], and characterized by single-crystal X-ray diffraction. Both materials were synthesized as phase-pure compounds through hydrothermal techniques using Tl2CO3 and HIO3 as reagents. The materials crystallize in space groups R-3 (Tl(IO3)3) and P-1 (Tl4(IO3)6). Although lone-pairs are observed for both I5+ and Tl+, electronic structure calculations indicate the lone-pair on I5+ is stereo-active, whereas the lone-pair on Tl+ is inert.  相似文献   

20.
When [HFe(CO)4]? is treated first with NaBiO3 and then dilute H2SO4, a complex mixture of neutral metal carbonyl clusters results, some of which can be extracted into petroleum ether. Upon prolonged standing the extract yields a precipitate which has been characterized by X-ray crystallography as Bi2Fe3(CO)9.The complex Bi2Fe3(CO)9 crystallizes in the centrosymmetric orthorhombic space group Cmcm (D2h17; No. 63) with a 10.616(2) Å, b 13.458(3) Å, c 11.347(3) Å, V 1621.1(7) Å3 and Z = 4. Single-crystal X-ray diffraction data (Mo-Kα, 2θ = 4.5–55.0°) were collected on a Syntex P21 four-circle diffractometer and the structure was refined to RF 5.4% and RWF 4.5% for all 1039 independent data (RF 4.5% and RWF 4.5% for those 851 reflections with |F0| > 3.0σ(|F0|)). The molecule lies on a site of crystallographic C2v symmetry and is disordered. The individual molecules have a trigonal bipyramidal Bi2Fe3 core with the bismuth atoms occupying the apical sites (BiFe 2.617(2)–2.643(2) Å, FeFe 2.735(5)–2.757(5) Å). Each iron atom is linked to three terminal carbonyl ligands and the molecule has approximate C3h symmetry. The nine peripheral oxygen atoms are ordered and define a tricapped trigonal prism. The equatorial iron atoms are disordered with the two Fe3 triangles mutually displaced by approximately 30°; the disordered ensemble has approximate D3h symmetry.  相似文献   

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