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1.
Oxoargentates(I) of Alkali Metals. On Na3AgO2 Na3AgO2 has been prepared anew (light pale-yellow powder samples; clear transparent single crystals). It crystallizes orthorhombic (space group Ibam) with a = 5.463, b = 10.926, c = 5.926 Å, Z = 4, d = 3.94 g X cm?3, dpyk = 3.89 g X cm?3; parameters are given in the text. The structure of Na3AgO2, marked by linear “dumb-bells” [O? Ag? O], d(Ag→O) = 2.09 Å is a novel variant of Na2O. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, have been calculated and are discussed.  相似文献   

2.
On K4PbO4 and Rb4PbO4 For the first time single crystals of K4[PbO4] have been prepared by heating K4PbO3 in O2. The structure has been refined [K4[PbO4]: 3029 I0(hkl), four circle diffractometer PW 1100, ω-scan, MoKα, R = 6.73%, Rw = 6.64%, P1 ; a = 658.62(15), b = 658.41(12), c = 986.64(21) pm, α = 79.74(2)°, β = 108.45(2)°, γ = 112.49(2)°, dx = 3.79 g · cm?3, dpyk = 3.78 g · cm?3, Z = 2; Rb4[PbO4]: a = 686.94(18), b = 684.43(18), c = 1020.73(21) pm, α = 79.28(2)°, β = 108.40(2)°, γ = 113.02(2)°, dx = 4.87 g · cm?3, dpyk = 4.85 g · cm?3, Z = 2, (from Rb2PbO3 and Rb2O)]. Both compounds are isotypic with K4SnO4. The Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated.  相似文献   

3.
On oxocadmates: The crystal structure of K2CdO2 According to single crystal data [438 hk0 — hk4; Mo — Kα] K2CdO2 crystallizes orthorhombic, space group No. 60, Pbcn — D, with a = 10.089, b = 6.186, c = 6.152 Å, Z = 4; d = 3.85 g · cm?3, dpyk = 3.61 g · cm?3 (for parameters see text). Though the space group is different from that of K2ZnO2, the similarities of the two crystal structures are unmistakable. The Madelung part of lattice energy is calculated and discussed.  相似文献   

4.
Crystal Structure of SrHg(SCN)4 · 3 H2O SrHg(SCN)4 · 3 H2O is orthorhombic, space group Pcca, with a = 19.476(7), b = 8.150(1), c = 8.991(3) Å, V = 1427.1 Å3, Z = 4, dc = 2.67 g · cm?3, μ(AgKα) = 77.95 cm?1. The salt consists of nearly tetrahedral Hg(SCN)4 groups, Sr has a tricapped trigonal prismatic coordination: four N and five O atoms. The thiocyanate groups form end-to-end bridges and connect the Hg and Sr coordination polyhedra.  相似文献   

5.
Rb2PbO3 [single crystals, 244 (hkl)] crystallises orthorhombic [D? Pmcn] with a = 10.8, b = 7.49, c = 5.98 Å [Z = 4, dpyk = 5.69, d = 5.80 g · cm?3], Rb in 8(d) Pb in 4 (c), OI in 4 (c). The parameters are shown in table 2. The MADELUNG Part of Lattice Energy of Rb2RBO3 and structurally related models are calculated and discussed in detail. Characteristic for the structure are ldimensional chains consisting of alternatingly directed pseudo-tetragonal pyramids, ∞1[PbO1O4/2], connected via common basis edges.  相似文献   

6.
New Oxozineates of Alkali Metals: Rb2[ZnO2] and Cs2[ZnO2] Colorless single crystals of the hitherto unknown Rb2[ZnO2] (a = 9.558, b = 6.335, c = 15.91 Å, β = 118.6°, z = 8, dpyk = 4.11, d = 4.21 g · cm?3) and Cs2[ZnO2] (a = 9.851, b = 6.619, c = 16.26 Å, β = 116.8°) have been prepared, which crystallize monoclinic, P21/c – D. (For parameters see text.) Unexpected there are “isolated” groups [Zn4O8]. Half of the Zn atoms exhibit the unusual coordination number 3 towards O2?. The Madelung Part of Lattice Energy, MAPLE, and the Effective Coordination Number, ECoN, the latter by means of Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.  相似文献   

7.
The Crystal Structure of Cs2S and a Remark about Cs2Se, Cs2Te, Rb2Se, and Rb2Te Cs2S crystallizes orthorhombic, a = 8.571, b = 5.383, c = 10.39 Å, Z = 4, d = 4.13, dpyk = 4.19 g · cm?3, D–Pnma with \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {{\rm Cs}}\limits^|,\mathop {{\rm Cs}}\limits^\parallel $\end{document} and S in 4(c) each, for parameter see text. It is R = 10,4% for 202 of 222 possible reflexes. There is a sequence of S2? corresponding to the hexagonal closest packing of sphares. Cs occupies half of “tetrahedron” and all “octahedron vacancies”; the deviation of \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {{\rm Cs}}\limits^|, $\end{document} in ?oktahedron vacancies”? is noticeable. Effective Coordination Numbers, ECoN, and the Madelung Part of Lattice Energy, MAPLE, are calculated and discussed.  相似文献   

8.
On Oxotitanates of the Alkaline Metals: On Na4Ti5O12 Colourless single crystals of the new titanate Na4Ti5O12 (starting from mixtures Na2O/TiO2, 1000°C, 6 d, Au-crucible, open system) crystallize in the monoclinic system, space group C2/m, a = 26.544(9), b = 2.952(1), c = 6.322(3) Å, β = 95.79(3)°, Z = 2, d = 3.45 and dpyk = 3.38 g · cm?3 (four-cycle-diffractometer data, PW 1100, 2?-scan, MoKα). R = 5.09% and Rw = 4.87% for 1178 independent I0(hkl) with 3° ≤ 2? ≤ 34°. Corrugated layers of Ti5O12, held together by Na+, are stacked along [001]. Details about partially occupied positions of Na+, Effective Coordination Numbers (ECoN), the Madelung part of lattice energy (MAPLE), and the structural differences to Na2Ti3O7 are discussed.  相似文献   

9.
New Borates of the Alkali Metals: KLi2[BO3] The hitherto unknown KLi2[BO3] is prepared in the shape of orthorhombic, colour-less-transparent, and columnar single crystals [a = 797.1(4) pm, b = 643.2(3) pm, c = 645.7(3) pm, Z = 4, dx = 2.25 g/cm3, dpyk = 2.20g/cm3]. The crystal structure was solved by four-cycle-diffractometer [PW 1100, MoKα, R = 5.78%, RW = 3.83%, 452 I0(hkl)]. Kli2[BO3] is sensitiv against atmospheric moisture which causes hydrolysis. Effective Coordination Numbers, ECoN, these via Mean Effective Ionic Radii, MEFIR, are calculated and discussed.  相似文献   

10.
[Cu(C8H22N4)]·(ClO4)2.H2O, Mr= 454.80, orthorhombic C2221, a = 15.481(5), b = 7.404(1), c = 14.827(3)Å, V = 1699.5(8)Å3, Z = 4, Dx = 1.78 g/cm3, λ(MoKα) = 0.71073Å, μ = 16.5 cm?1. F(000) = 940, T = 22°C, R = 6.86%, Rw = 7.66% for 820 observed reflections (I > 2.5σ (I)). The coordination number for the copper(II) ion is five, and the coordination geometry about copper(II) ion is a buckled square pyramid with the tetraamine equatorial and a perchlorate ion axial. The tetraamine is coordinated in a square-plannar manner with slight tetrahedral distortions. The four Cu-N distances span a very narrow range, 1.990(10) ?1.994(14)Å.  相似文献   

11.
“Fragmentation” and “Aggregation” on Lead Oxides. On the Oligooxoplumbate(IV) K2Li6[Pb2O8] For the first time, the dinuclear Oxoplumbate(IV) K2Li6[Pb2O8] has been prepared as transparent colourless single crystals by heating mixtures of K2PbO3, Li2O, and “PbO2” with K:Li:Pb = 1:3:1 e. g. [Ag-cylinders, sealed under vacuum in Supremax-glass ampoule, 660°C, 120 d]. The structure determination verifies the space group P1 with a = 6.9720(9), b = 5.9252(6), c = 5.9312(7) Å, α = 88.05(1)°, β = 107.94(1)°, γ = 107.30(1)°; dx = 4.95 g · cm?3, dpyk = 4.91 g · cm?3; Z = 1, [2107 symmetry independent hkl, fourcircle-diffractometer Philips PW 1100, ω—2Θ—scan, MoKα, R = 5.07%, Rw = 4.59%, absorption not considered]. The structure is characterized by the group [Pb2O8] — two edge connected (equatorial/apical) trigonal bipyramids — that is observed for the first time. Several ways of synthesis are given. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Effective Ionic Radii, MEFIR, are calculated.  相似文献   

12.
Bis(1-aminoguanidinium) sulfate monohydrate (AG2SO4 … H2O, 1), bis(1,3-diamino-guanidinium sulfate (DAG2SO4, 2), bis(1,3,5-triaminoguanidinium) sulfate dihydrate (TAG2SO4 … 2 H2O, 3) and bis(azidoformamidinium) sulfate (AF2SO4, 5) were synthesized and characterized by multinuclear NMR, IR, and Raman spectroscopy and elemental analysis. In the synthesis of 3, double protonated triaminoguanidinium sulfate (HTAGSO4, 4) was obtained as a byproduct. The molecular structures of 15 in the crystalline state were determined by low-temperature single crystal X-ray diffraction. 1: orthorhombic, Pnma, a = 6.7222 (8) Å, b = 14.153 (2) Å, c = 11.637 (1) Å, V = 1107.1(2) Å3, Z = 4, ρcalc.= 1.586 g cm?3 R1 = 0.0442, wR2 = 0.1007 (all data). 2: hexagonal, P6122, a,b = 6.6907 (1) Å, c = 43.4600 (8) Å, γ= 120°, V = 1684.86 (5) Å3, Z = 6, ρcalc.= 1.634 g cm?3, R1 = 0.0321, wR2 = 0.0714 (all data). 3: monoclinic, C2/c, a = 9.6174 (8) Å, b = 22.858 (1) Å, c = 6.7746 (5) Å, β= 109.49 (1), V = 1404.0 (4) Å3, Z = 4, ρcalc.= 1.620 g cm?3, R1 = 0.0292, wR2 = 0.0781 (all data). 4: monoclini c, P21/c, a = 8.9998 (9), b = 6.3953 (6), c = 13.3148(12) Å, β= 99.679 (8), V = 755.44 (13) Å3, Z = 4, ρcalc.= 1.778 g cm?3, R1 = 0.0305, wR2 = 0.0809 (all data); 5: orthorhombic, Pbca, a = 11.3855 (9), b = 7.1032 (6), c = 12.807 (1) Å, V = 1035.74 (14) Å3, Z = 4, ρcalc.= 1.720 g cm?3, R1 = 0.0389, wR2 = 0.0862 (all data).  相似文献   

13.
Note on Li2PdO2 For the first time we prepared ruby-red single crystals of Li2PdO2 by reaction with the wall 3 Na2O + Li2O2 + ?Tb4O7”?(+ Pd) = 3 Na2TbO3 + Li2PdO2 + ?TbO2”?, Pd-tube, 1100°C, 7 d. Single crystal data confirm the Li2CuO2-type of structure [a = 375.34(5), b = 298.18(4), c = 931.58(10) pm; spacegroup Immm; dx = 4.85 g · cm?3; 144 I0(hkl); R = 3.54%, Rw = 3.19%; MoKα ; four-circle diffractometer Philips PW 1100] and reveal clearly different parameters compared with those deduced by powder data. The Madelung Part of Lattice Energy, MAPLE, corresponds now to the sum of the MAPLE values of the binary oxides.  相似文献   

14.
The preparation of Tl2O and its crystal structure is discussed. By FOURIER methods for a monoclinic unit cell(aM = 6.082, bM = 3.520, cM = 13.24 Å, β = 108.2°, Z = 4, space group C2h3) the determined atomic parameters can be transformed into the trigonal system by the assumption of special oxygen positions (space group No. 166–R3 m). Correspondingly the Tl2O crystal structure may be described as a threefold polytype form of the anti CdJ2 type (aH = 3,516 cH = 37.84 Å; c/a = 10.76, Z = 6, mol. vol. = 40.7 cm3; dx = 10.44, dpyk = 10.4 g m?).  相似文献   

15.
Oxides of a New Type of Formula: On the Knowledge of K3Ni2O4 and K3Pt2O4 K3Ni3O4, greyblack single crystals, obtained by heating K2O and NaNiO2 [K:Ni = 2:1, 500°C, 7d, Ag-cylinders], crystallizes orthorhombic with a = 6.044, b = 9.049, c = 10.567 Å, Z = 4, space group Cmcm (d = 3.43, dpyk = 3.32 g · cm?3). Due to four cycle diffractometer data (374 hkl, MoKα, R = 8.6percnt;) a new type of structure is found with wavebands of [NiO4/2] \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm N}\limits^{\rm 1} $\end{document} exhibits the C.N. 6, \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm N}\limits^{\rm 2} $\end{document} the C.N. 4. Effective Coordination Numbers, ECoN, calculated by means of Mean Fictive Ionic Radii, MEFIR, the Madelung Part of Lattice Energy, MAPLE and the magnetic properties are discussed. K3Pt2O4, black single crystals with metallic lustre, obtained by heating KOx (x = 1.55 or 1.88) and Pt (powder) [K:Pt = 4:1,1000°C, lh, 600°C, 2d, Pt-capsules] is isotypic to K3Ni2O4 (four cycle diffractometer data: 458 hkl, MoKα, R = 12percnt;). Cellparameters are a = 6.15, b = 9.27, c = 11.51 Å (single crystal data), d = 5.79 and dpyk = 5.77 g · cm?3.  相似文献   

16.
Über KCuAIF6     
On KCuAlF6 KCuAlF6 has been prepared for the first time as colourless single crystals [from powder, Au-tube, 700°C, 70 d]. It crystallizes in the orthorhombic crystal system with a = 673.1, b = 704.0, c = 979.3 pm (dx = 3.49, dpyk = 3.4 g = cm?3) isotypic to CsAgFeF6 (Pnma, Z = 4, 727 hkl; MoKα, R = 5.6, Rw = 4.4%). Parameters see in the text. Strikingly we observe compressed “octahedra” [CuF6]. The compression (Δ = 11.6%) is nearly the same: CsAgFeF6 (Δ = 9.7%). The Madelung Part of Lattice Energy, MAPLE (for hypothetic forms, too) is calculated and discussed.  相似文献   

17.
New Borates of Alkali Metals: KNa2[BO3] We prepared hittherto unknown KNa2[BO3] in the shape of orthorhombic, colourlesstransparent and columnar single crystals [a = 603.9(2) pm, b = 560.2(3) pm, c = 556.8(2) pm, Z = 2, dx = 2.54 g/cm3, dpyk = 2.50 g/cm3]. The crystal structure was solved by four-cycle-diffractometer [PW 1100, MoKα , R = 3.73%, Rw = 2.88%, 386 I0(hkl)]. KNa2[BO3] is very sensitiv against atmospheric moisture, and hydrolysis takes place. Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, and the Madelung-Part of Lattice Energy, MAPLE, are calculated and discussed.  相似文献   

18.
About Perrhenates. 1. On LiReO4 For the very first time anhydrous LiReO4 was prepared in transparent, colourless single crystals from Li2O2 and Re2O7 (closed Au-pipe; 350°C; 14 d). The crystal structure, P1 , with a = 9.652(1), b = 8.455(1), c = 6.928(1) Å, α = 101,53° (1), β = 106.55° (1), γ = 97.22° (1), Z = 6, dx = 4.92 g/cm3, dpyk = 4,81 g/cm3 was solved (four-circle-diffractometer data PW 1100, 2151 I0 (hkl), AgKα; R = 0.073, Rw = 0.076). There are three kinds of functionally different Li+. The Madelung Part of the Lattice Energy, MAPLE, was calculated.  相似文献   

19.
Crystal structures of Cs4[Re6Te8(CN)6]·2H2O (1) and Ba2[Re6Te8(CN)6]· 12H2O (2) are determined. Crystals 1 are orthorhombic, a = 14,282(1), b = 12.910(1), c = 18.040(1) Å, Vcell = 3326.3(8) Å3, space group Pbcn, Z = 4, dcalc = 5.715 g/cm3, R(F) = 0.0482 for 3193 Fhkl > 4σ(F). Crystals 2 are triclinic, a = 9.671(3), b = 9.697(4), c = 11.039(4) Å, α = 89.86(3), β = 72.34(3), γ = 82.46(3)°, Vcell = 977.2(6) Å3, space group P1, Z = 1, dcalc = 4.733 g/cm3, R(F) = 0.0490 for 3226 Fhkl > 4σ(F). In both structures, the [Re6Te8(CN)6]4? anions form a distorted primitive cubic packing with distances between the centers 9.02-9.63 Å in 1 and 9.70-11.04 Å in 2. The Cs+ cations in 1 lie near the face centers of the cubes formed by the onions. In 2, cation pairs (Ba2+)2 bonded to two solvate water molecules are formed; the pairs lie at the centers of the anion cubes. In structures 1 and 2, there are shortened contacts between the tellurium atoms belonging to the neighboring anions (3.75-4.09 and 3.95-4.22 Å, respectively).  相似文献   

20.
K2Zn3O4 and Rb2Zn3O4, Oxozincates with Framework Structure For the first time single crystals of K2Zn3O4 were obtained by heating mixtures of the binary oxides (K: Zn = 2.2:3) in sealed Ag- or Pt-capsules at 800°C (5 w). Powder of this colourless and moisture-sensitive oxide was prepared analogously at 500°C. It crystallizes monoclinic, space group C2/c with a = 1482.7(2), b = 637.3(1), c = 571,9(1) pm, β = 102.79(1)°, Z = 4, dx = 4.265 g/cm3, dpyk = 4.00 g/cm3. The crystal structure was determined from four-circle diffractometer data (MoKα, 730 unique hkl) and refined to R = 5.9%, Rw = 6.4%. It shows a Zn3O4 framework which consists of SiS2-like chains [ZnO4/2] connected by puckered layers of [ZnO3/3]. The crystal structure can be derived from a cubic closet packing of O2? and K+. Effective Coordination Numbers and the Madelung Part of Lattice Energy (MAPLE) are calculated. Rb2Zn3O4 was prepared from the binary oxides at 400°C (colourless hygroscopic powder). According to powder data it crystallizes isostructural to K2Zn3O4 with a = 1523.5(4), b = 649.8(2), c = 574.0(2) pm, β = 101.43(3)°, Z = 4, dx = 5.141 g/cm3, dpyk = 5.20 g/cm3.  相似文献   

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