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1.
More Silicates with ?Stuffed Pyrgoms”?: CsKNaLi9{Li[SiO4]}4, CsKNa2Li8{Li[SiO4]}4, RbNa3Li8{Li[SiO4]}4 [1] and RbNaLi4{Li[SiO4]}2 [2] Single crystals of the new silicates CsKNaLi9{Li[SiO4]}4, CsKNa2Li8{Li[SiO4]}4, RbNa3Li8{Li[SiO4]}4 and RbNaLi4{Li[SiO4]}2 as well as powder (Rb-containing compounds only) were obtained for the first time. The samples were prepared by heating well ground mixtures of the binary oxides in Ni and Ag tubes, respectively. The structure determination was carried out by four-circle diffractometer data (MoKα radiation; Siemens AED 2): CsKNaLi9{Li[SiO4]}4: tetragonally prismatic crystals, light yellow; 726 I0(hkl), R = 4.4%, Rw = 2.8%; a = 1 102.0(6), c = 637.9(5) pm; Z = 2; space group I4/m; 2 CsO0.55 + Li4TlO4 + glas (560°C, 15 d). CsKNa2Li8{Li[SiO4]}4: tetragonally prismatic crystals, light yellow; 727 I0(hkl), R = 4.4%, Rw = 2.6%; a = 1 103.5(7), c = 637.7(4) pm; Z = 2; space group I4/m; 1.1 CsO0.61 + 1.1 KO0.55 + 1.4 NaO0.52 + 6.5 Li2O + 4 SiO2 (600°C, 60 d). RbNa3Li8{Li[SiO4]}4: tetragonally prismatic crystals, colourless; 600 I0(hkl), R = 2.3%, Rw = 2.0%; a = 1 092.08(6), c = 632.76(4) pm; Z = 2; space group I4/m; 4 RbO0.57 + 3 NaO0.52 + 6.5 Li2O + 4 SiO2 (650°C, 63 d). RbNaLi4{Li[SiO4]}2: monoclinic, ball-shaped, colourless; 1 224 I0(hkl), R = 3.1%, Rw = 3.1%; a = 1 573.10(13), b = 630.48(5), c = 781.25(8) pm, b = 90.566(8)°; Z = 4; space group C2/m; 1.1 RbO0.52 + 1.2 NaO0.45 + 5 Li2O + 4 SiO2 (700°C, 40 d).  相似文献   

2.
The First Titanate with ?Stuffed Pyrgoms”?: RbNa3Li12[TiO4]4 = RbNa3Li8{Li[TiO4]}4 By heating a well grounded mixture of the binary oxides Rb2O, Na2O, Li2O, and TiO2 [Rb:Na:Li:Ti = 1.1:3.1:12.5:4.0; 780°C, 41 d] we obtained RbNa3Li8{Li[TiO4]}4 as colourless platelike crystals. This first titanate with ?stuffed pyrgoms”? is isostructural with RbNa3Li8{Li[SiO4]}4, CsKNa2Li8{Li[SiO4]}4 and CsKNaLi9{Li[SiO4]}4 [2]. The compound crystallizes tetragonal I4/m with a = 1 125.8(1) pm and c = 652.4(1) pm (Guinier-Simon-Data, Z = 2). The structure was determined by four-cyrcle-data (Siemens AED2, MoK) and leds to the residual values R = 3.7% and Rw = 3.1% (additional data see text). The Madelung Part of Lattice Energy (MAPLE), Effective Coordination Numbers (ECoN), Mean Fictive Ionic Raddii (MEFIR) and the Charge Distribution in Solids (CHARDI) are calculated and discussed.  相似文献   

3.
A “Lithosilicate” with Columnar Units: RbLi5{Li[SiO4]}2 In order to prepare RbLi3[SiO4] single crystals of RbLi5{Li[SiO4]}2 have been obtained for the first time by heating of a well ground mixture of the binary oxides RbO0.68, LiO0.5 and SiO2 [Rb:Li:Si = 1.1:3.0:1.0; 600°C; 21 d] in tightly closed Ni tubes. The new “lithosilicate” crystallizes monoclinic (space group C2/m with a = 1563.1(2) pm, b = 635.4(1) pm, c = 776.3(1) pm, β = 90.53(1)°, Guinier-Simon powder data). The crystal structure was determined by four-cycle diffractometer data [Philips PW 1100, 1237 from 1609 Io(hkl), Z = 4, R = 9.2%, Rw = 8.3%], parameters see text. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, have been calculated.  相似文献   

4.
The First “Litho-Manganate(V)” with Layer-Structure: Cs2{Li[MnO4]} By heating intimate mixtures of the oxides [CsO1,2, Li2MnO3; Cs: Mn = 2,3 : 1; Ag-Zylinder, 580°C, 62 d] blue-green single crystals of Cs2{Li[VO4]} were obtained for the first time. The new “Litho-Manganate(V)” crystallices orthorhombic (SG: Cmc21) with a = 596.08(7), b = 1202.6(1), c = 816.8(1) pm (Guinier-Simon data), Z = 4. It is isotypic with Cs2{Li[VO4]} [1]. The structure was determined by four-circle-diffractometer data [Mo? Kα , for 496Io(hkl) R = 3.1%, R, = 2.4%], parameters see text. The Madelung Part of Lattice Energie, MAPLE and Effective Coordination Numbers, ECoN, these calculated via Mean Fictive Ionic Radii, MEFIR, are calculated and disscussed.  相似文献   

5.
A New Oxogermanate: Li8GeO6 ? Li8O[GeO4] Transparent colourless single crystals of Li8GeO6(P63cm, a = 550.09(8), c = 1072.2(3) pm, Z = 2; 4-circle-diffractometer Siemens AED 2, MoKα; 326 Io(hkl), R = 2.4%, Rw = 2.0%), have been prepared. As by-product we always got colourless isometric single crystals of Li4GeO4. For the first time we could grow single crystals of Li8SiO6 of suitable size and quality. Our structure refinement confirms the assumed structure model [2]: Li8GeO6 and Li8SiO6 are isotypic with Li8CoO6[3] (Li8SiO6: a = 542.43(8), c = 1062.6(2) pm, Z = 2; 4-circle-diffractometer Siemens AED 2, MoKα; 306 Io(hkl), R = 3.6%, Rw= 3.0%). The known crystal structure of Li4GeO4 [4] is confirmed and refined (Cmcm, a = 776.6(2), b = 735.7(3), c = 604.9(2) pm, Z = 4; 4-circle-diffractometer Siemens AED 2, MoKα, 298 Io(hkl), R = 1.9%, Rw = 1.4%). The Madelung Part of Lattice Energy, MAPLE, and Effective coordination-Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated.  相似文献   

6.
Chains consisting of Rings: K5{Li[Ge2O7]} — the First ‘Litho-Digermanate’ By heating of a well-ground mixture of the binary oxides KO0.55, Li2O and GeO2 (K: Li: Ge = 6.1 : 2.2 : 2; Ni-tube; 600°C; 49 d) we obtained for the first time single crystals of K5{Li[Ge2O7]}. This ‘lithodigermanate’ represents a completely new type of structure: monoclinic, space group P21/c, a = 624.9(2) pm, b = 1586.6(8) pm; c = 1058.3(6) pm and β = 109.38(4)°; Guinier-Simon data, Z = 4. The structure was solved by four-circle diffractometer data [Siemens AED II, Mo? Kα ; 2872 Io(hkl); R = 4.5%, Rw = 3.3%], parameters see text. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these calculated via Mean Fictive Ionic Radii, MEFIR, as well as charge distribution CHARDI, are calculated and discussed.  相似文献   

7.
About Cs2Li2[GeO4] By heating of a well-ground mixture of the binary oxides CsO0.55, Li2O and GeO2 (Cs:Li:Ge=2,6:2,2:1; Ni-tube; 600 °C; 49d) we got single crystals of Cs2Li2[GeO4] for the first time. Cs2Li2[GeO4] is isotypic to Rb2Li2[MO4] [M = Si, Ti, Ge] [2] and Cs2Li2[MO4] (M = Si, Ti) [3]: according to this Cs2Li2[GeO4] crystallizes triclinic, in the spacegroup P1 with a = 968.7(4) pm, b = 586.0(2) pm, c = 571.4(2) pm, α = 92.71(4)°, β = 110.95(3)° and γ = 94.34(4)° (Guinier-Simon data), Z = 2. The structure was determined by four-circle diffractometer data (Ag? Kα ; 2381 Io(hkl); R = 8,4%; Rw = 5.0%), parameters see text. Further the Madelung Part of Lattice Energy (MAPLE), Effective Coordination Numbers (ECoN) and the Mean Fictive Ionic Radii (MEFIR), have been calculated.  相似文献   

8.
The First Diniobate with ‘Isolated’ Anions: KLi4[NbO5]=K2Li8[Nb2O10] [1] . By heating of well ground mixtures of the binary oxides [K2O, Li2O, Nb2O5, K:Li:Nb=1.1:4.4:1, Pt-tube, 1100°C, 3d] colourless, triclinic single crystals of KLi4NbO5 have been prepared for the first time: space group P1 (Nr. 2) with a=816.9(2) pm, b=592.2(2) pm, c=589.7(2) pm, α=121.00(2)º, β=91.78(2)°, γ=99.23(2)°, Z=2. The crystal structure was solved by four-cycle diffractometer data [Mo-Kα , 1386 from 1386 Io(hkl), R=3.4%, Rw=2.6%], parameters see text. Characteristic for this structure are “isolated” groups of [Nb2O10] and the tetrahedral coordination of Li(1), Li(2), and Li(3). Li(4) has a tetragonal-pyramidal coordination. The structural relations are deduced by Schlegel Diagrams. The Madelung Part of Lattice Energy, MAPLE, the Effective Coordination Numbers, ECoN and the charge distribution have been calculated and discussed.  相似文献   

9.
An Oxomanganate(V) of New Type: K11{Li[OMnO3]}4 By heating of well ground mixtures of the oxides [K2O2, LiMnO4, K:Mn = 2.2:1, Ag-tube, 580°C, 30 d] blue-green tetragonal single crystals of K11{Li[OMnO3]4} have been prepared for the first time: space group I4 2m; a = 787,18(7) pm, c = 1750.9(3) pm. The structure was determined by four-circle-diffractometer data [MoKα , 1236 from 1303 Io(h kl), R = 3.9%, Rw = 3.1%], parameters see text. The Madelung Part of Lattice Energy, MAPLE, and the Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, have been calculated.  相似文献   

10.
Li10Si2PbIIO10 = Li20[(SiO4)4(OPbO2PbO)] — The first ?mixed”? Silicate-Plumbate(II) Colourless crystals of Li10Si2PbO10 were obtained by heating a well-ground mixture of LiPb, Li2O2 and ?SiO2”? (deriving from Duran glas) in Ag-tubes (650°C; 60 d). The crystal structure was determined (four-circle diffractometer data, Mo? K, 1 474 Io(hkl), R = 4.2%, Rw = 2.8%, parameters see text). The silicate-plumbate crystallizes monoclinic (space group C2/m; I. T. No. 12) with a = 2985.1(4); b = 610.6(6); c = 512.8(1) pm, β = 99.70(9)° (four-circle data), Z = 4. Further the Madelung Part of Lattice Energy (MAPLE), Effective Coordination Numbers (ECoN), the Mean Fictive Ionic Radii (MEFIR) and the Charge Distribution (CHARDI) are being calculated.  相似文献   

11.
Li3InO3 crystallises trigonal, P3 c1, with a = 9.6064, c = 10.420 Å, c/a = 1.0647, Z = 12 and In1 in 2(a), In2: 4(d), In3: 6(f), and O1, O2, O3, Li1, Li2, Li3 each in 12 (g). According to Li2[4]{In□1/3}O2 Li3InO3 is a “stuffed derivative” of a layer structure of the CdJ2 type. Calculations of the Madelung Part of Lattice Energy [MAPLE] assure the localisation of Li by X-Ray work and explain why In2, O1, O2, and O3 depart from “ideal” positions.  相似文献   

12.
The First ?Lithovanadate”?: K2{LiVO4} By heating of well ground mixtures of the binary oxides [K2O, Li2O, V2O5, K:Li: V = 2.2:1.1:1.0; Ni-tube, 900°C, 46 d] colourless monoclinic single crystals of K2[LiVO4] have been prepared for the first time: space group C2/m; a = 835.7(1) pm, b = 774.5(1) pm, c = 753,3(1) pm, β = 90.23(1)°. The structure was determined by four-circle diffractometer data [MoKα, 1018 form 1262 I0 (hkl), R = 8.65%, Rw = 5.67%], parameters see text. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, have been calculated.  相似文献   

13.
Two New Silicate-Chlorides with Divalent Europium: LiEu3[SiO4]Cl3 and Li7Eu8[SiO4]4Cl7 LiEu3[SiO4]Cl3 was prepared by reaction of LiCl with Eu2SiO4 and Li7Eu8[SiO4]4Cl7 from Li with Eu2O3, SiO2 and LiCl. The crystal structures of LiEu3[SiO4]Cl3 (Pmna, a = 946.95(13); b = 699.52(8); c = 1 368.0(2) pm; Z = 4; R1 = 0.0325, R2w = 0.0642) and Li7Eu8[SiO4]4Cl7 (P21/c; a = 851.85(5); b = 948.62(7); c = 1 679.0(2) pm; β = 96.221(8)°; Z = 2; R1 = 0.0352, R2w = 0.0744) were determined from four-circle diffractometer data. LiEu3[SiO4]Cl3 contains [Li(SiO4)2] units and LiCl6 octahedra while in Li7Eu8[SiO4]4Cl7 larger ?lithosilicate”? groups are found. In both structures, the Eu2+ ions are coordinated mostly eightfold by O2? and Cl? ligands.  相似文献   

14.
The compounds Li8EN2 with E = Se, Te were obtained in form of orange microcrystalline powders from reactions of Li2E with Li3N. Single crystal growth of Li8SeN2 additionally succeeded from excess lithium. The crystal structures were refined using single‐crystal X‐ray diffraction as well as X‐ray and neutron powder diffraction data (I41md, No. 109, Z = 4, Se: a = 7.048(1) Å, c = 9.995(1) Å, Te: a = 7.217(1) Å, c = 10.284(1) Å). Both compounds crystallize as isotypes with an anionic substructure motif known from cubic Laves phases and lithium distributed over four crystallographic sites in the void space of the anionic framework. Neutron powder diffraction pattern recorded in the temperature range from 3 K to 300 K and X‐ray diffraction patterns using synchrotron radiation taken from 300 K to 1000 K reveal the structural stability of both compounds in the studied temperature range until decomposition. Motional processes of lithium atoms in the title compounds were revealed by temperature dependent NMR spectroscopic investigations. Those are indicated by significant changes of the 7Li NMR signals. Lithium motion starts for Li8SeN2 above 150 K whereas it is already present in Li8TeN2 at this temperature. Quantum mechanical calculations of NMR spectroscopic parameters reveal clearly different environments of the lithium atoms determined by the electric field gradient, which are sensitive to the anisotropy of charge distribution at the nuclear sites. With respect to an increasing coordination number according to 2 + 1, 3, 3 + 1, and 4 for Li(3), Li(4), Li(2), and Li(1), respectively, the values of the electric field gradients decrease. Different environments of lithium predicted by quantum mechanical calculations are confirmed by 7Li NMR frequency sweep experiments at low temperatures.  相似文献   

15.
Zusammenfassung Die Kristallstruktur von Li2GeO3 wird mit Hilfe dreidimensionalerFourier-Synthesen und nach der Methode der kleinsten Quadrate bestimmt. Li2GeO3 ist isotyp mit Li2SiO3 und enthält [GeO3]2–-Ketten (Zweiereinfachkette). Die Gitterparameter der rhombischen Elementarzelle (C 2v 12 –Cmc21) betragen:a=9,630,b=5,465 undc=4,850 Å. Als mittlere interatomare Abstände wurden erhalten: Ge–O=1,74 und Li–O=2,01 Å.
The crystal structure of Li2GeO3 has been determined by means of 3-dimensional Fourier syntheses and least-squares method. Li2GeO3 is isostructural with Li2SiO3, containing [GeO3]2–-chains (Zweiereinfachkette). The lattice parameters of the orthorhombic cell (C 2v 12 –Cmc21) are:a=9,630;b=5,465 andc=4,850 Å. The average interatomic distances are found to be: Ge–O=1,74 and Li–O=2,01 Å.


Mit 3 Abbildungen  相似文献   

16.
New Alkalioxoarsenates (V). On Rb2Li[AsO4] and Cs2Li[AsO4] By heating of well-grounded mixtures of the binary oxides (A2O, Li2O2, and As2O3; A : Li : As = 2 : 1 : 1; Ni-tube, 550°C, 21 d; A = Rb, Cs) colourless single crystals of Rb2Li[AsO4] and Cs2Li[AsO4] were obtained for the first time. These new orthoarsenates(V) crystalize orthorhombic (space group C mc21? C, No. 36) with Z = 4. As expected they are isotypic with the according orthovanadates(V) [2] A2Li[VO4], A = Rb, Cs. The lattice constants of Rb2Li[AsO4]: a = 582.1(4) pm, b = 1171.1(7) pm, c = 792.4(5) pm and Cs2Li[AsO4]: a = 596.4(2) pm, b = 1223.4(2) pm, c = 819.7(3) pm were taken from Guinier-Simon powder data. The structure was determined by four-circle-diffractometer data [Siemens AED II, MoKα , 6290 I0 (hkl), R = 3.5%, Rw = 3.2% to Rb2Li[AsO4]; 3518 I0 (hkl), R = 2.8%, Rw = 2.6% to Cs2Li[AsO4]; parameters see text]. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these calculated via Mean Fictive Ionic Radii, MEFIR, as well as charge distribution CHARDI are calculated and discussed.  相似文献   

17.
Na2Li3CoO4, the First Quaternary Oxocobaltate(III) of the Alkali Metals For the first time we obtained Na2Li3CoO4 by annealing intimate mixtures of Co3O4, Na2O2, and Li2O [Co : Na : Li = 1 : 2.2 : 10.1; 760°C; 21 d; Ag-tube] in form of transparent red single crystals. Structure Refinement [four-circle diffractometer data; AED2; MoKα-radiation; 1016 Io(hkl); R = 2.6%; Rw = 2.0%; space group Pnnm; Z = 4; a = 818.7(3), b = 799.4(2), c = 655.1(2) pm] confirms the isotypism to Na2Li3GaO4 [2] and Na2Li3FeO4 [3]. Mean Fictive Ionic Radii, MEFIR, Effective Coordination Numbers, ECoN, and the Charge Distribution were calculated. The isotypism of Na2Li3CoO4 and Na2Li3GaO4 is compared graphically.  相似文献   

18.
On Oxides of the New Formula Type A[T4O4]: KLi3SiO4, KLi3GeO4, and KLi3TiO4 The crystal structure of KLi3GeO4 has been determined from single crystal x-ray diffraction data. The unit cell is triclinic, space group P1 , a = 10.278(2), b = 7.511(1), c = 5.849(1) Å, α = 100.32(2), β = 110.07(2), γ = 90.32(2)°; Z = 4, R = 0,0867, Rw = 0,0793. Cubes of the composition KO8/2 form chains parallel to [11 1] and are interlinked by tetrahedrally coordinated Li+ and Ge4+. KLi3SiO4 and KLi3TiO4 are isotypic. Effective coordination numbers (ECoN) and the Madelung part of lattice energy (MAPLE) have been calculated.  相似文献   

19.
The crystal structure of the compound Li3Zn0.5GeO4 has been determined and refined by means of three-dimensionalFourier syntheses and least squares. Li3Zn0.5GeO4 crystallizes orthorhombic with space groupD 2h 16 -Pmnb (No. 62) and the lattice parametersa=6.29,b=10.74 andc=5.17 Å. The crystal structure consists of isolated [GeO4] tetrahedra, which are linked together by [(Li,Zn)O4] tetrahedra analogous to Li3PO4(h). An additional eight-fold position is partly occupied by two lithium atoms. The occupancy of this position may vary according to the observed range of composition, which lies between Li3.8Zn0.1GeO4 and Li2.6Zn0.7GeO4.
  相似文献   

20.
On ?Lithovanadates”?: Rb2[LiVO4] and Cs2[LiVO4] By heating of well ground mixtures of the binary oxides [A2O, Li2O, V2O5, A : Li: V = 2.2 : 1.1 : 1.0 (A = Rb, Cs); Ni-tube, 750° 25 d] we obtained Rb2[LiVO4] and Cs2[LiVO4] colourless, orthorhombic single crystals. We found a new type of ?Lithovanadate”?-structure: space group Cmc21; a = 587.9(1), b = 1170.1(1), c = 793.3(1) pm, Z = 4 (A = Rb) bzw. a = 610.5(1), b = 1222.6(3), c = 815.5(2) pm, Z = 4 (A = Cs). The structure was determined by four-circle diffractometer data [MoKα -radiation; 997 from 1157 I0(hkl), R = 7.75%, Rw = 5.54% (A = Rb); 686 from 686 I0(hkl), R = 6.97%, Rw = 4.20% (A = Cs)] parameters see text. The Madelung part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, have been calculated.  相似文献   

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