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1.
A Change of Structure Type in the Oxides BaCoGd2O5, BaCoDy2O5, and BaCoY2O5 (I) BaCoGd2O5, (II) BaCoDy2O5, and (III) BaCoY2O5 were prepared for the first time and examined by single crystal work. (I) and (II) belong to the BaNiLn2O5-type. (I): a = 3.770; b = 5.860; c = 11.620 Å; Z = 2; (II): a = 3.755; b = 5.798; c = 11.514 Å; Z = 2; space group D–Immm. (III) crystallizes in the BaCuLn2O5-type, space group D–Pnma, a = 12.287; b = 5.713; c = 7.067 Å; Z = 4. The coordination of Co2+ changes from (I, II) to (III) from octahedral to tetragonal pyramidal.  相似文献   

2.
The Crystal Chemistry of Copper Rare-Earth Oxotungstates: (I): triclinic-α-CuTbW2O8, (II): monoclinic-CuInW2O8 and (III): monoclinic-CuYW2O8 Single crystals of (I), (II) and (III) were prepared by recrystallisation in closed systems and examined by X-ray technique. (I): space group C? P1 , a = 7.3080, b = 7.8945, c = 7.1476 Å, α = 115.23, β = 116.21, γ = 56.98°, Z = 2; (II): space group C? C2/c, a = 9.6576, b = 11.6496, c = 4.9863 Å, β = 91.17°, Z = 4; (III): space group C? P2/n, a = 10.0504, b = 5.8214, c = 5.0224 Å, β = 94.23°, Z = 2. The crystal structures are discussed with respect to calculations of the coulombterms of lattice energy and possible valence states of Cu2+ and Mo5+.  相似文献   

3.
A Contribution on CuPrMo2O8 and CuTbMo2O8 Single crystals of (I): CuPrMo2O8 and (II): CuTbMo2O8 were prepared by solid state reactions in closed copper tubes. They crystallize with orthorhombic symmetry, space group D-Pbca, (I): a = 10.4114, b = 9.8917, c = 14.8287 Å, (II): a = 10.2243, b = 9.7385, c = 14.6000, Z = 8. Both compounds are isotypic to CuYMo2O8, showing isolated MoO4 tetrahedra, square antiprismatic coordination of Ln3+ and Cu+ besides one edge of an O2? triangle. Calculations of the coulombterm of lattice energy support the oxidation state Cu2+ in combination with mixed valences of Mo6+ and Mo5+ on the molybdenum point positions.  相似文献   

4.
A Contribution on the Crystal Structure of CuYW2O8, CuHoW2O8, and CuYW2O8 Single crystals of (I) CuY2O8, (II), CuHoW2O8, and (III) CuYbW2O8 were prepared and investigated by X-ray technique. (I) crystallizes with triclinic symmetry, space group C? P1 (a = 5.939 Å, b = 6.042 Å, c = 5.025 Å; α = 112.30°, β = 111.77°; Z = 1). (II) and (III) belong to monoclinic symmetry, space group C? P2/n (II) (a = 10.045 Å, b = 5.808 Å, c = 5.021 Å; β = 94.38°; z = 2 (III) a = 9.948 Å, b = 5.824 Å, c = 5.008 Å; β = 93.36°; Z = 2). The crystal structures will be discussed with respect to other to copper rare earth tungstates.  相似文献   

5.
A Contribution on the Compound CaBeNd2O5 and Phases of the Composition M1?xMx'BeLn2O5 (M = Ca, Ba; M′ = Sr; x = 0.5). CaBeNd2O5 and the phases (I): Ba0,5Sr0,5BeLa2O5 and (II): Ca0,5Sr0,5BeDy2O5 have been prepared by high temperature reactions using a CO2-LASER. They crystallize with orthorhombic symmetry, space group D-Pnma, CaBeNd2O5: a = 9.448(1), b = 7.155(1), c = 6.483(1) Å; (I) a = 9.821(4), b = 7.436(3), c = 6.734(3) Å; (II): a = 9.352(2), b = 7.016(2), c = 6.375(2) Å; Z = 4, and belong to the isotypic series CaBeLn2O5 and SrBeLn2O5. Calculations of Coulomb energies of ordered BaBeLn2O5 and EuBeLn2O5 and disordered CaBeLn2O5, SrBeLn2O5 and EuBeNd2O5 show dependencies of the ionic radii of the M2+ and Ln3+ ions as well as of the order/disorder state.  相似文献   

6.
A Contribution on the Crystal Structure of CuSmMo2O8 and CuGdMo2O8 Single crystals of (I) CuSmMo2O8 and (II) CuGdMo2O8 were prepared and investigated using an X-ray technique. Both compounds crystallize with orthorhombic symmetry, space group D-Pbca with Z = 8. ((I): a = 10.302, b = 9.796, c = 14.697 Å; (II): a = 10.200, b = 9.779, c = 14.646 Å). The crystal structure and the classification into the already known Copper(I) Lanthanoidemolybdates are discussed.  相似文献   

7.
Synthesis and Structure of the First Ternary Lead(II) Copper(I) Oxide: PbCu2O2 PbCu2O2 can be prepared by solid state reaction or by precipitation from a basic aqueous solution. Single crystals of the new compound were prepared by recrystallisation from a molten mixture (PbO? Cu2O) and investigated by X-ray diffractometer technique. PbCu2O2 crystallizes isotypically with the homologue silver compound PbAg2O2 (monoclinic with a = 8.223 Å, b = 8.289 Å, c = 6.015 Å, β = 132.62°, Z = 4, space group C? C 1 2/c 1). The crystallographic data from the X-ray investigation are reported. The structure is built by endless [PbO4/4]- and [CuO2/4]-chains. Pb2+ has a one-sided asymmetric coordination with four next oxygen neighbours and Cu+ forms a stretched dumbbell with two oxygen atoms.  相似文献   

8.
A New Crystal Structure of ABLn2O5 Compounds. About BaNiNd2O5 The compound BaNiNd2O5 was prepared by solid state reaction. Single crystal examination show a new structure type (a = 3.829(2), b = 5.932(3), c = 11.649(3) Å space group D–Immm, Z = 2) with Ni2+ in octahedral coordination. The surrounding of Ba2+ and Nd3+ conforms to BaPtNd2O5 with significant differences of the polyhedra connection.  相似文献   

9.
Synthesis and Investigation of NiNb2O6 Single Crystals of Columbite and Rutil Type C-NiNb2O6 (columbite type) and R-NiNb2O6 (rutil type) single crystals were prepared by solid state reactions. C-NiNb2O6 a = 14.032; b = 5.687; c = 5.033 Å, space group D—Pbcn. R-NiNb2O6 a = 4.710; c = 3.038 Å, space group D—P42/mnm. The metal positions of the rutil structure are statisticaly occupied by Ni2+ and Nb5+ ions. R-NiNb2O6 is in respect to lower temperatures a metastable compound.  相似文献   

10.
On the Atomic Distribution in Ba2SrIn2O6 with a Contribution to the Existence of the Calciumferrite-Type of Oxoindates (I) Ba2SrIn2O6 and (II) Sr0.93Ba0.07In2O4 were prepared and investigated by single crystal X-ray technique. I crystallizes with tetragonal symmetry, space group D – I4/mmm, a = 4.168; c = 21.290 Å; Z = 2; II belongs to the orthorhombic space group D – Pnma, a = 9.858; b = 3.273; c = 11.520 Å; Z = 4. I shows in respect to the formerly investigated compound BaSr2In2O6 an unexpected statistically distribution of Ba2+ and Sr2+ with the La2SrCu2O6 type. II marks the range of existence of the calciumferrite type within the alkaline earth oxoindates in direction of large radii of M2+ ions.  相似文献   

11.
CuTb[B5O10]: The first “Metaborate” with a [B5O10]5? Anion Single crystals of the new compound CuTb[B5O10] were obtained by a B2O3 flux-technique. They crystallize in a so far unknown structure. X-ray investigations on single crystals led to the space group C–I ba2 (Nr. 45); a = 6.294(1) Å; b = 8.406(8) Å; c = 12.733(2) Å; Z = 4. The structure contains [B5O10]5? chains isolated from each other. These chains include twelf membered rings of boron and oxygen. Each ring consists of two tetrahedral BO4 and two planar B2O5 groups and is connected with the next one via the BO4 units. Tb3+ is eightfold- and Cu2+ elongated octahedraly coordinated by oxygen.  相似文献   

12.
New Compounds with Zinc in Square Pyramidal Coordination: BaZnDy2O5 and Ba1.25ZnHo2O5.25 (Ba5Zn4Ho8O21). Single crystals of (I): BaZnDy2O5 and (II): Ba5Zn4Ho8O21 were prepared by high temperature reactions and investigated by X-ray technique. (I) belongs to the BaCuLn2O5 type, space group D-Pbnm; a = 7.084; b = 12.368; c = 5.728 Å, Z = 4. (II) is isotypic to Ba5Mn4Ln8O21, space group C-I4/m; a = 13.779; c = 5.707 Å, Z = 2. The two different structure types are caused by the small difference in the composition of 0.25 BaO. Analogies and differences will be discussed. In addition the lattice constants of powder samples of Ba5Zn4Ln8O21 (Ln = Eu, Gd, Dy, Ho, Er and Y) are given.  相似文献   

13.
On a Barium Rare Earth Oxozincate/Platinate(IV): Ba2Eu2ZnPtO8 High temperature reactions of BaCO3, ZnO and Eu2O3 in platinum crucibles led to single crystals of Ba2Eu2ZnPtO8. It crystallizes with orthorhombic symmetry, space group D-Pnma, a = 13.390(1), b = 5.764(1), c = 10.387(1) Å, Z = 4 and is isotypic to Ba2Y2CuPtO8. Ba2Eu2ZnPtO8 is characterized by isolated 1[ZnPtO8]10? anions formed by ZnO5-pyramids and PtO6-octahedra. The space between the [ZnPtO8]10? groups is filled by Eu3+ and Ba2+ ions. Relationships to zinc and platinum containing oxometallates are discussed.  相似文献   

14.
Crystal Chemistry of the Lead Lanthanide Oxoaluminates. On Pb2HoAl3O8 and Pb2LuAl3O8 . Single crystals of (I) Pb2HoAl3O8 and (II) Pb2LuAl3O8 were prepared by flux technique and investigated by X-ray methods. It crystallizes with cubic symmetry, space group O–P42/n 3 2/m, (I): a = 9.4164(13) Å, (II): a = 9.3486(8) Å, Z = 4. The new structure type shows AlO4 tetrahedra, LnO8 hexagonal bipyramids and one sided coordinated Pb2+ within heterocubane units. The crystal chemical relationships to other lead oxides containing heterocubane Pb4O4 units are discussed.  相似文献   

15.
Synthesis and Structure of a New form of CuYMo2O8 Single crystals of a new form of CuYMo2O8 were prepared and investigated by X-ray diffractometer technique [space group D-Pbca; a = 10.160 Å, b = 9.701 Å, c = 14.527 Å; Z = 8]. CuYMo2O8 represents a new structure type characterised by MoO4-tetrahedrons, Cu+ with coordination number 2 + 1 and square antiprisms around Y3+. The crystal structure and the Cu+ coordination are discussed.  相似文献   

16.
LaCl(BO2)2 and Er2Cl2[B2O5]: Two Chloride Oxoborates of Trivalent Lanthanides Er2Cl2[B2O5] is obtained as single crystals by the reaction of ErCl3, Er2O3 and B2O3 with an excess of ErCl3 as flux in evacuated silica tubes after two weeks at 850 °C. The compound crystallizes as long, pale pink needles and appears to be air‐ and water‐resistant. Single‐crystalline LaCl(BO2)2 emerges from the reaction of La2O3, LaCl3, and B2O3 with an excess of B2O3 as flux in evacuated silica tubes after four weeks at 900 °C. LaCl(BO2)2 crystallizes as thin, colourless, air‐ and water‐resistant needles which tend to severe twinning due to their fibrous habit. The crystal structure of Er2Cl2[B2O5] (orthorhombic, Pbam; a = 1489.65(9), b = 1004.80(6), c = 524.86(3) pm; Z = 4) contains two crystallographically different erbium cations. (Er1)3+ resides in pentagonal‐bipyramidal coordination of seven anions while (Er2)3+ is surrounded by only six anions with the shape of an octahedron. The planar oxodiborate units [B2O5]4— consisting of two vertex‐shared [BO3]3— triangles are isolated according to {([BOO]2)4—}. LaCl(BO2)2 crystallizes isostructurally with PrCl(BO2)2 in the triclinic space group P1¯ (a = 423.52(4), b = 662.16(7), c = 819.33(8) pm; α = 82.081(8), β = 89.238(9), γ = 72.109(7)°; Z = 2). The characteristic unit consists of endless chains built up by corner‐linked [BO3]3— triangles. These quasi‐planar zigzag chains of the composition {[(B1)OO(B2)OO]2—} (≡ {[BO2]} run parallel [100]. The La3+ cations exhibit coordination numbers of ten and are coordinated by three Cl and seven O2— anions.  相似文献   

17.
On the First Alkaline Earth Mercurato(II)-Palladate(II, IV): Ba2Hg3Pd52+Pd24+O14 Single crystals of Ba2Hg3Pd7O14 were prepared by oxygen high-pressure technique (3900 bar) and investigated by X-ray technique. It crystallizes with monoclinic symmetry, space group C–C2/m; Z = 2 (a = 10.583; b = 6,207; c = 10.919 Å, β = 90.56°). The Hg2+ ions show partially dumb-bell like and one sided 3 fold coordination respectively. Pd4+ /Pd2+ show an octahedric or square planar surrounding.  相似文献   

18.
The Crystal Structure of Cu2M(BO3)O2 (M = Fe3+, Ga3+) Single Crystals of the compounds Cu2M(BO3)O2 (M = Fe3+ (I), Ga3+ (II)) were obtained by a B2O3 flux-technique. They crystallize in a monoclinic distorted variant of a Ludwigite structure with a partly ordered metal distribution. X-ray investigations on single crystals led to the space group C–P21/c (No. 14); I: a = 3.108(1); b = 12.003(1); c = 9.459(3) Å; b? = 96.66(3)°; Z = 4 and II: a = 3.1146(2); b = 11.921(3); c = 9.477(2) Å; b? = 97.91(2)°; Z = 4. All metal-sites are distorted octahedraly coordinated by oxygen-ions. The structure contains isolated planar BO3-units and oxygen which is not coordinated to boron.  相似文献   

19.
Two New Alkaline-Earth-Oxoindates: BaCa2In6O12 and BaSr2In6O12 The hitherto unknown compounds (I): BaCa2In6O12 and (II): BaSr2In6O12 were prepared and examined by single crystal X-Ray work. (I) and (II) crystallize with hexagonal symmetry, space group C? P63/m, with (I): a = 9.880, c = 3.211 Å; (II): a = 9.9443; c = 3.2671 Å, Z = 1. Both compounds are isotypic to the metastable oxide AM2Ln6O12, but without metastable behavior. The [In6O12]6? network is occupied by the alkaline earth ions. One of the tunnels is stuffed by Ca2+ and Sr2+ respectively, the other one by Ba2+ in a statistical distribution on possible point positions. (I) and (II) prove the existence of the AM2Ln6O12-type in respect to small Ln3+ ions.  相似文献   

20.
On Alkaline Earth Metal Oxothallates. II. Preparation and Crystal Structure of Ba2Tl2O5 Ba2Tl2O5 was prepared and investigated by X-ray single crystal methods (space group D? Pcmn, a = 6.264, b = 17.258, c = 6.05 Å) Ba2Tl2O5 is isotypic with Ca2Fe2O5.  相似文献   

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