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1.
Metal Pseudohalides. XL. Dicyanamido Metallates [M{N(CN)2}4]2? of Palladium(II) and Platinum(II) The synthesis of homologeous tetrakis-(dicyanamido) metallates(II), [M{N(CN)2}4]2? is reported. The coordination type of the ambivalent dicyanamide ligand is discussed on the basis of the i.r. and n.m.r. spectra of the new complexes.  相似文献   

2.
Metal Pseudohalides. XXXIX. Dicyanamide Complexes of Palladium(II) and Platinum(II) of the Type M{N(CN)2}2L2 The synthesis of mixed dicyanamide complexes of the type M{N(CN)2}2L2 (M: Pd, Pt) is reported. Infrared and NMR-spectroscopic investigations are indicating the hitherto undescribed coordination type M? N(CN)2 of the anionic ligand.  相似文献   

3.
On the Structure of Sr3(BN2)2 The structure of Sr3(BN2)2 was determined on single-crystal X-ray data collected with a four-circle diffractometer. Sr3(BN2)2 crystallizes in the cubic space group Im3 m (no. 229) with a = 764.56(3) pm and Z = 3. The structure contains linear BN3?2 ions with a B? N bond length of 135.8(6) pm. The straight forward synthesis employing metal nitrides plus boron nitride yielded crystalline powders of M3(BN2)2 (M = Ca, Sr) at 1100°C (5 days). Cubic indexing of guinier patterns gave a = 765.8(1) pm for M = Sr and a = 734.7(2) pm for M = Ca. The structure refinement on a single crystal of Sr3(BN2)2 revealed that one strontium site (2a; 0, 0, 0) is occupied by only about 50%. It has been tried to fully occupy this site with an alkali metal (A) to obtain ASr4(BN2)3 (Z = 2). Reactions with A = Na yielded crystalline powders. Cubic indexing of the guinier pattern analogous to that of Sr3(BN2)2 gave a = 754.2(1) pm.  相似文献   

4.
The X-ray powder patterns of H3Co(CN)6 and Ag3Co(CN)6 have been indexed on the basis of a hexagonal unit cell: The length of the N? X? N-bond along the c-axis is 3.29 Å for X ? H and 4.24 Å for X ? Ag. These distances are in agreement with data obtained from infrared spectra and with structural properties of similar compounds.  相似文献   

5.
Metal Pseudohalides. 28. Remark on the I.R. Absorption of the Coordination Polymeric Compounds M(C(CN)3)2 in the Region of 200–400 cm?1 The infrared spectra of the tricyanmethanides of 3d metals M(C(CN)3)2 (M = Mn, Fe, Co, Ni, Cu, Zn) in the region of 200–400 cm?1 are reported. Significant absorption bands between about 220 and 290 cm?1 are assigned to M—N-stretching frequencies.  相似文献   

6.
The crystal structures of Co3[Co(CN)6]2, 12 H2O (a, = 10.210 ± 0.005 Å) and Cd3[Co(CN)6]2, 12 H2O (a = 10.590 ± 0.005 Å) have been determined by X-ray powder methods. According to the measured density the unit cell contains 1 1/3 formula units with 4 Co2+ (Cd2+) in 4a, 2 2/3 Co3+ in 4b, 16 C and 16 N in 24e, 8 H2OI near 24e, (96k) and 8 H2OII near 8 c (192 l). Structure factor calculations based on the space group Oh5 - F m 3 m lead to the following final values of the reliability index R: 0.038 (Co3[Co(CN)6]2, 12 H2O) and 0.037 (Cd3[Co(CN)6]2, 12 H2O). The interatomic distances for the cobaltous compound (in parentheses for the cadmium compound) are: Co3+-C: 1.88 Å (1.89); C-N: 1.15 Å (1.17); Co2+-N: 2.08 Å (2.24); Co2+-OI: 2.10 Å (2.27); shortest OI-H-OII-bonds: 2.89 Å (2.82). Co3+ is octahedrally coordinated by six carbon atoms, the divalent metal ion by four nitrogen atoms and two water molecules. The two different metal ions are connected by M2+-N-C-Co3-bonds to a threedimensional network. The infrared and electronic spectra are shown to be in agreement with the results of the structure analyses of these compounds. The observed positions of the OH-stretching vibrations lead to a hydrogenbond-length of 2.8–2.95 Å.  相似文献   

7.
Crystal Structure of the Basic Dimercury(I) Nitrates. III. Crystal Structure of Hg4O2(NO3)2 Hg4O2(NO3)2 crystallizes monoclinic, space group P21/a – standard setting P21/c (C) – with a = 1158.0(2), b = 666.4(1), c = 553.3(1) pm, β = 98.82(1)° and Z = 2. The structure determination from single crystal diffractometer data (AgKα, 1170 I0(hkl), numerical absorption corrections applied) resulted in a final R = 0.0512 (Rw = 0.0685). The mixed valence compound is built up of puckered layers [(HgII)2/2O(Hg)1/2]+ parallel (201). Within the layers there are exclusively covalent Hg? Hg and Hg? O bonds; whereas the linkage between the layers is achieved by weak HgI? O contacts and by nitrate ions functioning as weak bridging ligands for mercury atoms. This layer structure explains the distinct cleavage of crystals of Hg4O2(NO3)2.  相似文献   

8.
Preparation and Crystal Structures of Ag[N(CN)2](PPh3)2, Cu[N(CN)2](PPh3)2, and Ag[N(CN)2](PPh3)3 The coordination compounds Ag[N(CN)2](PPh3)2 ( 1 ), Cu[N(CN)2](PPh3)2 ( 2 ), and Ag[N(CN)2](PPh3)3 ( 3 ) are obtained by the reaction of AgN(CN)2 or CuN(CN)2 with triphenylphosphane in CH2Cl2. X‐ray structure determinations were performed on single crystals of 1 , 2 , and 3 · C6H5Cl. The three compounds crystallize monoclinic in the space group P21/n with the following unit cell parameters. 1 : a = 1216.07(9), b = 1299.5(2), c = 2148.4(3) pm, β = 99.689(13)°, Z = 4; 2 : a = 1369.22(10), b = 1257.29(5), c = 1888.04(15) pm, β = 94.395(7)°, Z = 4; 3 · C6H5Cl: a = 1276.6(4), b = 1971.7(3), c = 2141.3(5) pm, β = 98.50(3)°, Z = 4. In all structures the metal atoms have a distorted tetrahedral coordination. The crystal structure of 3 · C6H5Cl shows monomeric molecular units with terminal coordinated dicyanamide. The crystal structure of 1 is built up by dinuclear units, which are bridged by dicyanamide ligands. However, the crystal structure of 2 corresponds to a onedimensional coordination polymer, bridged by dicyanamide anions.  相似文献   

9.
Two new dicyanamide coordination polymers, {Mn(dmpz)[N(CN)2]2}2 (1) and {Cu(dmpz)[N(CN)2]2}2 (2)(dmpz=3,5-dimethylpyrazole), were synthesized and characterized by single crystal X-ray diffraction analysis and IR spectroscopy. In 1 and 2 the metal ions have two different coordination modes, where one is coordinated to four dicyanamide anions and two monodentate dmpz molecules to form a slightly distorted octahedral geometry, while the other adopts octahedral geometry, surrounded by four nitrile N atoms and two amide N atoms of the dicyanamide anions. Both complexes contain two alternating chains that are parallel to each other.  相似文献   

10.
Zusammenfassung Die Kristallstruktur eines weiteren Defekt-Mangansilicids (Mn27Si47) wird bestimmt.
The crystal structure of the defect manganese silicide, Mn27Si47
The atomic parameters of Mn27Si47 have been determined.


Mit 2 Abbildungen  相似文献   

11.
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13.
The Crystal Structure of the Basic Dimercury (I) Nitrates. I. The Crystal Structure of Hg2OH(NO3) · Hg2(NO3)2 The unit cell of Hg2OH(NO3) · Hg2(NO3)2 is orthorhombic, space group Cc2a - standard setting Aba2 (C) — with a = 2017.1(5) pm, b = 935.8(3) pm, c = 1121.7(3) pm and contains 8 formula units. Characteristic are chains [Hg2OH(Hg2)2/2]3+ parallel [001]. These are interconnected to a three-dimensional network by nitrate ions coordinated to mercury. The structure achieves additional stabilization through weak hydrogen bonds between oxygen atoms of the hydroxy groups and neighbouring nitrate ions. The bonding relationship of one hydrogen atom to four tetrahedrally correlated oxygen atoms is discussed.  相似文献   

14.
Einkristalle von SrAl2O4 wurden durch Hochtemperaturreaktionen von SrO mit Al2O3 dargestellt und röntgenographisch untersucht (a = 844,7; b = 881,6; c = 516,3 pm;β = 93,42°; Raumgruppe C–;P21, Z = 4). Die Tetraederabfolge in den Sechsringen dieser aufgefüllten Tridymit-Struktur wird mit der ähnlicher Oxometallate verglichen. Compound Formation MeO:M2O3. IV. Structure of Monoclinic SrAl2O4 Single crystals of SrAl2O4 were prepared by high temperature CO2-LASER technique and investigated by X-ray methods. (a = 844.7; b = 881.6; c = 516.3 pm; β = 93.42°; space group C–P21, Z = 4). The orientation of the tetrahedra in this stuffed tridymite structure is discussed in comparison with related oxometallates.  相似文献   

15.
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   

16.
Gadolinium dicyanamide dihydrate Gd[N(CN)2]3 · 2 H2O was prepared by ion exchange in aqueous solution followed by evaporation of the solvent at room temperature. Gd[N(CN)2]3 · 2 H2O was characterized by single‐crystal structure analysis, FTIR spectroscopy and DSC analysis. In the crystal there are three crystallographically independent [N(CN)2]? ions and Gd3+ which are coordinated by six N atoms from six different [N(CN)2]? ions and two O atoms from two water molecules forming an irregular quadratic antiprism. Four H bonds have been identified in the structure of Gd[N(CN)2]3 · 2 H2O, two of them running to terminal N atoms and two to the bridging N atoms of dicyanamide ions (Gd[N(CN)2]3 · 2 H2O: P21/n (no. 14), a = 7.4845(15) Å, b = 11.529(2) Å, c = 13.941(3) Å, β = 93.98(3)°, Z = 4, 1948 reflections, 175 parameters, R1 = 0.0493). The DSC analysis indicates that Gd[N(CN)2]3 · 2 H2O looses the crystal water at temperatures around 130 – 140 °C forming anhydrous Gd[N(CN)2]3, the structure of which has been refined by the Rietveld method based on X‐ray powder diffraction data. Gd[N(CN)2]3 was found to be isotypic with Ln[N(CN)2]3 (Ln = La, Ce, Pr, Nd, Sm and Eu) which previously have been described in the literature.  相似文献   

17.
18.
Metal Sulfur Nitrogen Compounds. 20. Reaction Products of PdCl2 and Pd(CN)2 with S7NH. Preparation and Structure of the Complexes [Ph6P2N][Pd(S3N)(S5)] and X[Pd(S3N)(CN)2] X = [Me4N]+, [Ph4P]+ With PdCl2 and [Ph6P2N]OH S7NH forms the complex salt [Ph6P2N][Pd(S3N)(S5)], which could be isolated in two modifications (α- and β-form). The α-form is triclinic, a = 9.347(4), b = 14.410(8), c = 15.440(11) Å, α = 76.27°(5), β = 77.06°(4), γ = 76.61α(4), Z = 2, space group P1 . The β-form is orthorhombic, a = 9.333(2), b = 17.659(4), c = 23.950(6) Å, Z = 4. The structure of the metal complex is the same in the two modifications. One S3N? and one S52? are coordinate as chelate ligands to Pd. From S7NH, Pd(CN)2, and XOH X = [(CH3)4N]+ and [(C6H5)4P]+ the salts X[Pd(S3N)(CN)2] were formed. The (CH3)4N-salt is isomorphous with the analogous Ni compound described earlier, the (C6H5)4P-salt is triclinic, a = 9.372(4), b = 10.202(5), c = 13.638(6) Å, α = 86.36α(4), β = 85.66°(4), γ = 88.71°(4), Z = 2, space group P1 . One S3N? chelate ligand and two CN? ions are bound to Pd. In all these complexes the coordination of Pd is nearly square planar.  相似文献   

19.
On the Crystal Structure of Melem C6N7(NH2)3 Single crystals of melem ( 1 ) were grown from both DMSO‐solutions and the gas phase. The structure of melem ( 1 ) was solved by single‐crystal X‐ray diffraction (P21/c, Z = 4, a = 741.66(15), b = 862.28(17), c = 1335.9(3) pm, β = 99.91(3)° R1 = 0.037 for 1098 reflections). The structure determination by X‐ray powder diffraction, which has been previously conducted, is in agreement with our data. The increased quality of the structural information allows for a more detailed understanding of the hydrogen bonding network.  相似文献   

20.
Anionie Nickel Pseudohalide Complexes of the Types [Ni{N(CN)2}3]? and [Ni{N(CN)2}2(NCS)2]2? The preparation of a new type of anionic pseudohalide complexes of nickel [Ni{N(CN)2}3]? and of mixed thiocyanate-dicyanamide complexes [Ni{N(CN)2}2(NCS)2]2? is reported. The structures of the complexes are discussed on the basis of IR- and magnetic measurements. The new compounds are representing polymer octahedral complexes with a bridging function of the dicyanamide ligands.  相似文献   

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