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1.
On Complex Fluorides with Cu2+ and Pd2+: MPtF6 (M ? Pd, Cu) and RbCuPdF5 For the first time single crystals of PdPtF6 (green), trigonal-rhomboedric, a = 503.8, c = 1431.6 pm, spcgr. R3 ? C (No. 148), Z = 3, CuPtF6 (orange), triclinic, a = 495.2, b = 498.5, c = 962.4 pm, α = 89.98, β = 104.23, γ = 120.35°, spcgr. P1 ? C (No. 2), Z = 2 and RbCuPdF5 (orange brown, in connection with investigations on MIPd2F5 [1]), orthorhombic, a = 626.9, b = 719.9, c = 1076.3 pm, spcgr. Pnma? D (No. 62), Z = 4, four circle diffractometer data, have been obtained.  相似文献   

2.
First Magnetoplumbite Structure Including Rare Earth Ions: Nd2Fe Fe Al9O38 The hitherto unknown compound Nd2Fe15Al9O38 with magnetoplumbite structure was prepared. The symmetry of the isolated red-brown single crystals was determined by X-ray single crystal work (space group D? P63//mmc; a = 568.7; c = 2 223 pm; Z = 2) and the distribution of Fe and Al to the metal positions was identified.  相似文献   

3.
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   

4.
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   

5.
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   

6.
The Reaction of MeO:M2O3. A New Structure Type: SrCa2Sc6O12 The compound Sr0.33Ca0.67Sc2O4 shows a hitherto unknown hexagonal crystal structure (a = 9.659, c = 3.136 Å; Space group C?P63/m). A detailed discussion of the coordination polyhedrals and the similarity to CaSc2O4 are given.  相似文献   

7.
Photoluminescence of Trivalent Rare Earths in Perovskite Stacking Polytypes Ba2La2?x RE MgW2□O12, Ba6Y2?x RE W3□O18, and Sr8SrGd2?xRE W4□O24 Rhombohedral 12 L stacking polytypes Ba2La2?xREMgW2□O12 show with RE3+ = Pr, Sm, Eu, Tb, Dy, Ho, Er, Tm; the 18 L stacking polytypes Ba6Y2?xREW3□O18 and the polymorphic perovskites Sr8SrGd2?xREW4□O24 with RE3+ = Sm, Eu, Dy, Ho, Er visible photoluminescence. The concentration dependence and the influence of the coordination number of the rare earth are reported.  相似文献   

8.
On the Crystal Structure of MnF3 and MnPtF6 Single crystal investigations of MnF3 (rubyred) confirmed the crystal structure based on powder data [2]: monoclinic, space group C 2/c?C (No. 15) with a = 892.02 pm, b = 504.72 pm, c = 1 347.48 pm, β = 92.64° with Z = 12. The corresponding determination of the crystal structure of MnPtF6, yellow, confirmed the unit cell [3] with a = 510.47 pm, c = 1 421.0 pm and γ = 120°, Z = 3 space group R 3 -C (No. 148). For both compounds detailed parameters respectively interatomic distances have been obtained.  相似文献   

9.
The Crystal Structure of Perovskites A NiIIMVIO6. II. Sr2NiWO6 The results of an X-ray single crystal study of the perovskite Sr[NiIIWVI](6)O6, ordered in the octahedral sites, are given. While Sr[NiIITeVI](6)O6 crystallizes in a monoclinically deformed structure of the perovskite (elpasolite) type, showing a phase transition to a tetragonal lattice at 675 °K, Sr[NiIIWVI](6)O6 is tetragonal already at 298°K (space group: C; a = b = 5.559 Å; c = 7.918 Å; Z = 2). The Ni? O distances found for the tungsten compound are nearly identical with those of the tellurium perovskite. In contradiction to crystal field theory very different values of the ligand field parameter Δ (ca. 25%) are observed for these two compounds however. Obviously this effect is caused by the rather different kind of bonding within the NiO6 polyhedra in the two compounds. On the basis of the structural results the Ni? O-bonding in the two perovskites is discussed in dependence of the next nearest cationic environment.  相似文献   

10.
About Ba6La2Co4O15 Ba6La2Co4O15 were prepared and investigated by X-ray single crystal work. It crystallizes with hexagonal symmetry, space group C–P63mc; a = 11.8082; c = 7.0019 Å; Z = 2. Ba2+ show face connected BaO6-octahedra and larger polyhedra of C.N. = 10 and 12. Co3+ is surrounded by four and six (tetrahedra, octahedra) oxygen. The Ba2+ and La3+ ions occupy one point position statistically.  相似文献   

11.
Determination of Structures of Ordered Perovskites of the Ba2B MVIO6 Type Intensity calculations on powder patterns of Ba2Y□0.33MVIO6 with MVI = U, W, Te und Ba2Gd0.670.33UO6 lead for the space group Fm3m/O with 8 Ba in 8c, 8/3 BIII and 4/3 □ in 4b, 4 MVI in 4a and 24 O in 24e to R values between 4.3 and 7.6%. Two further models are discussed.  相似文献   

12.
Two coordination polymers {[Cd(phen)](C6H8O4)3/3} ( 1 ) and {[Cd(phen)](C7H10O4)3/3} · 2H2O ( 2 ) were structurally characterized by single crystal X‐ray diffraction methods. In 1 (C2/c (no. 15), a = 16.169(2)Å, b = 15.485(2)Å, c = 14.044(2)Å, β = 112.701(8)°, U = 3243.9(7)Å3, Z = 8), the Cd atoms are coordinated by two N atoms of one phen ligand and five O atoms of three adipato ligands to form mono‐capped trigonal prisms with d(Cd‐O) = 2.271‐2.583Å and d(Cd‐N) = 2.309, 2.390Å. The [Cd(phen)] moieties are bridged by adipato ligands to generate {[Cd(phen)](C6H8O4)3/3} chains, which, via interchain π—π stacking interactions, are assembled into layers. Complex 2 (P1¯(no. 2), a = 9.986(1)Å, b = 10.230(3)Å, c = 11.243(1)Å, α = 66.06(1)°, β = 87.20(1)°, γ = 66.71(1)°, U = 955.7(2)Å3, Z = 2) consists of {[Cd(phen)](C7H10O4)3/3} chains and hydrogen bonded H2O molecules. The Cd atoms are pentagonal bipyramidally coordinated by two N atoms of one phen ligand and five O atoms of three pimelato ligands with d(Cd‐O) = 2.213—2.721Å and d(Cd‐N) = 2.329, 2.372Å. Through interchain π—π stacking interactions, the {[Cd(phen)](C7H10O4)3/3} chains resulting from [Cd(phen)] moieties bridged by pimelato ligands are assembled in to layers, between which the hydrogen bonded H2O molecules are sandwiched.  相似文献   

13.
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   

14.
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   

15.
Preparation and Properties of CeTe2O and ThTe2O6, Compounds with a New Superstructure of the Fluorite Type It is demonstrated that in the systems MO2/TeO2 (with M = Ce, Th), treated in air and at 600°C, only phases of composition MTe2O6 are formed. They pertains to the cubic crystal system and constitutes a new type of fluorite-superstructure. Different aspects of its crystal chemistry are commented and also the infrared spectra are recorded and briefly discussed.  相似文献   

16.
The Structures of the Hexagonal Elpasolite-Type Compounds Ba3NiSb2O9 and Ba3CuSb2O9 The results of an X-ray single crystal study of the hexagonal elpasolite Ba(NiSb2)(6)O9 are given. (Space group: C; a = b = 5.837 Å, c = 14.392 Å; Z = 2). The structure can be described by close-packed BaO3 layers alternating in the sequence c c h c c h … (hex. BaTiO3 type). Groups of two octahedra with common faces are connected by SbO6 octahedra via common corners. They are occupied alternately by Ni and Sb. The final reliability index was R = 3.0%. The Cu2+-compound is of the same structural type. The ligand field and EPR spectra are discussed in comparison with related Ni2+ and Cu2+ compounds.  相似文献   

17.
Synthesis and Crystal Structure of Cu6Mo5O18 Single crystals of the hitherto unknown compound Cu6Mo5O18 were prepared and investigated by X-ray methods (a = 18.884(19), b = 6.273(7), c = 15.259(23) Å, β = 130.40(5)°, space group C–C2/c, Z = 4). The typical features of the structure are described and compared with the crystal chemistry of oxocuprates(I). Observed and calculated powder patterns show that the correct composition of the earlier described compound Cu6Mo4O15 is Cu6Mo5O18.  相似文献   

18.
On Hexagonal Perovskites with Cationic Vacancies. XVI. Rhombohedral 12 L-Stacking Polytypes Ba3AIIIM □O12 with MV = Nb, Ta The white quaternary oxides Ba3LaM□O12 with MV = Nb, Ta belong to the group of hexagonal perovskites with cationic vacancies. They crystallize in a rhombohedral 12 L-structure (sequence (hhcc)3; space group R3 m) with a = 5.751 Å; c = 28.11 Å (MV = Nb); a = 5.746 Å; c = 28.20 Å (Ta) and Z = 3. Signs for the formation of isotypic compounds with AIII = Pr, Nd could be obtained as well.  相似文献   

19.
Investigations in the System PO ? WO ? H2O? H3O+ By means of the molar ratio and Job'S method of continuous variations modified by us the composition of heteropolytungstates was determined using for the first time UV absorption spectroscopic techniques. For the case of the 1P:12W complex it is shown: In Na2HPO4 solutions acidified with HCl only the 12-tungstophosphate anion [PW12O40]3? is formed. The complex formation in dependence on the acid degree Z is complete at Z = 23 H3O+/12 WO = 1.92. For Z = 2.0 the consumption of H3O+ has been calculated to be 5 moles H3O+/1 mole HPO. Using Babko'S dilution method the stability constant of [PW12O40]3? was determined to be βk = 2.4 · 1012 l2 · mole?2.  相似文献   

20.
Preparation and Spectroscopic Characterization of the Cluster Anion [(Mo6Cl )(CF3COO) ]2? On heating of [(Mo6Cl)Cl]2? in dichloromethane with trifluoroacetic acid the new stable cluster anion [(Mo6Cl)(CF3COO)]2? is formed by elimination of HCl. The (Mo6Cl) unit remains unattacked. The 19F nmr spectrum exhibits a downfield shifted singulett as compared to free CF3COO? indicating the equivalence of all trifluoroacetate ligands, which unidentate coordination is deduced from characteristic i. r. frequencies of the carboxyl groups. The most intense i.r. band at 501 cm?1 is assigned to the antisymmetric Mo? Oa vibration, the most intense Raman line at 319 cm?1 to the breathing mode of the Cl cube.  相似文献   

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