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1.
On Ag2SnO3, the First Silver Stannate For the first time, crystals of red Ag2SnO3 have been obtained by solid state reaction of freshly prepared K2Sn(OH)6 and Ag2O at 430°C while applying an oxygen pressure of 350 bar. Ag2SnO3 shows a one dimensional incommensurate superstructure with a′ = 33.1 Å. Here we report on the basic structure of Ag2SnO3. According to the results of X-ray crystal structure determination the basic structure of Ag2SnO3 may be described in P6322 (a = 5.6230(4) Å, c = 12.6694(14) Å, Z = 4, 968 independent reflections, R1 = 5.6%, wR2 = 12.5%). Within the layered “SnO3” partial structure two third of the octahedral voids are occupied by tin. Those SnO3 layers are connected to each other by almost linearly coordinated silver atoms. Additionally, silver occupies the free octahedral voids within the SnO3 sheets. As expressed by the formula Ag[Ag1/3Sn2/3]O2 the structure may be described as a super structure of Delafossite CuFeO2.  相似文献   

2.
New Ternary Selenides of Lanthanoides by Reduction of Sesquiselenides The compounds MLn2Se3 (M = Na; Ln = La? Sm) and MLn8Se12 (M = Na, Ca; Ln = La? Sm) were prepared by reduction of the corresponding lanthanide sesquiselenides with sodium and calcium, respectively, for the first time. Further-more MLa8Se12 (M = Sr, Eu) could be obtained in an analogous way. All compounds were characterized by chemical analysis and X-ray powder diffraction. The electronic structures of these compounds were investigated by band structure calculations and magnetic measurements.  相似文献   

3.
Na4AuTl, the First Ternary Compound in the System Sodium/Gold/Thallium Silver coloured, brittle single crystals of Na4AuTl were obtained by the reaction of NaN3, gold sponge and TlN3 at 773 K. The structure was determined from X-ray single-crystal diffractometry data: Na4AuTl crystallizes in a new structure type with separated gold and thallium partial structures. These consist of linear [Au2/2] chains and [Tl2] dumb-bells. Structural relationships between Na2Au and the Na Au partial structure of Na4AuTl are discussed.  相似文献   

4.
Li2H4I2O10, the First Tetrahydrogendimesoperiodate Li2H4I2O10 has been obtained as an intermediate during the dehydration of LiH4IO6 · H2O to LiIO4, for the first time. According to the results of an X-ray structure determination (monoclinic, P21/n, a = 533.98(4), b = 471.85(4), c = 1431.48(10) pm, β = 91.614(7)°, Z = 2, 726 diffractometer data, R = 0.056), Li2H4I2O10 contains the previously unknown tetrahydrogendimesoperiodate ion H4I2O102?, consisting of two edge-shared IO6 octahedra. They are connected with LiO6 octahedra via common edges and vertices. The crystals are non-merohedrally twinned along (100).  相似文献   

5.
KEu(CH3COO)3, the First Ternary Europium(II) Acetate On of EuCl2 with a melt of dry potassium acetate yields pale greenish-yellow single crystals (300°C, sealed glass ampoule, EuCl2 and K(CH3COO) in a molar ratio of 1 : 3). The crystal structure determination (orthorhombic, P212121 (no. 19), Z = 8, a = 1166.3(1) pm, b = 1288.4(2) pm, c = 1493.9(2) pm, R = 0.043, Rw = 0.032) revealed the composition KEu(CH3COO)3. The structure consists of one-dimensional chains built up by bridging acetate groups in the [100] and [001] directions in which potassium and europium alternate as central atoms. Eu2+ is surrounded by nine and eight and K+ by seven and six oxygen atoms, respectively. These chains are linked in the [010] direction so that a three-dimensional network is formed. The high coordination numbers of the acetate oxygen atoms of up to four are remarkable. Therefore, the acetate groups have highly bridging functions in addition to their chelating coordination of the cations.  相似文献   

6.
Li2Br(NH2): The First Ternary Alkali Metal Amide Halide The pseudobinary system LiNH2/LiBr was investigated by X-ray methods. The crystal structure of the compound Li2Br(NH2) was solved by single crystal data: Li2Br(NH2): Pnma, Z = 8, a = 12.484(2) Å, b = 7.959(1) Å, c = 6.385(1) Å, Z(Fo) with (Fo)2 ≧ 3σ(Fo)2 = 348, Z (parameter) = 51, R/Rw = 0.019/0.021 Li2Br(NH2) crystallizes in a new type of structure. To one another isolated chains of [Li2Li4/2(NH2)22+] show the motif of closest rod packing. They are connected via bromide ions in a distorted cubic primitive arrangement.  相似文献   

7.
The reaction of W6Br12 with AgBr in evacuated silica tubes (temperature gradient 925 K/915 K) yielded brownish black octahedra of Ag[W6Br14] ( I ) and yellowish green platelets of Ag2[W6Br14] ( II ) both in the low temperature zone. ( I ) crystallizes cubically (Pn3 (no. 201); a = 13.355 Å, Z = 4) and ( II ) monoclinically (P21/c (no. 14); a = 9.384 Å, b = 15.383 Å, c = 9.522 Å, β = 117.34°, Z = 2). Both crystal structures contain isolated cluster anions, namely [(W6Bri8)Bra6]1– and [(W6Bri8)Bra6])]2–, respectively, with the mean distances and angles: ( I ) d(W–W) = 2.648 Å, d(W–Bri) = 2.617 Å, d(W–Bra) = 2.575 Å, d(Bri…Bri) = 3.700 Å, d(Bri…Bra) = 3.692 Å, ∠W–Bri–W = 60.78°. ( II ) d(W–W) = 2.633 Å, d(W–Bri) = 2.624 Å, d(W–Bra) = 2.613 Å, d(Bri…Bri) = 3.710 Å, d(Bri…Bra) = 3.707 Å, ∠W–Bri–W = 60.23°. The Ag+ cations are trigonal antiprismatically coordinated in ( I ) with d(Ag–Br) = 2.855 Å, but distorted trigonally planar in ( II ) with d(Ag–Br) = 2.588–2.672 Å. The structural details of hitherto known compounds with [W6Br14] anions will be discussed.  相似文献   

8.
The crystal structure of the title compound (C22H17BrO5 , Mr = 441.27) has been determined by single-crystal X-ray diffraction. The crystal is of orthorhombic system, space group Pna21 with a = 11.76(1), b = 14.58(1), c = 11.52(1), V = 1973.93 , Z = 4, Dc = 1.485 g/cm3 , F(000) = 896, μ(MoKα) = 2.113 mm-1 , the final R = 0.0394 and wR = 0.0809 for 3918 observed reflections (Ⅰ > 2 (Ⅰ)). The single-crystal X-ray diffraction data indicate that the C=C bond is in an E-configuration. The intramolecular C(10)-H(10B)···O(4) and intermolecular C(17)-H(17)···O(4) hydrogen bonds contribute to the stability of the structure.  相似文献   

9.
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   

10.
Ag3BiO3 and Ag5BiO4,the first Silver Oxobismuthates(III) Applying high oxygen pressures (100 MPa) Ag3BiO3 and Ag5BiO4 were prepared for the first time by reacting the binary components Ag2O and Bi2O3 at temperatures between 770 and 800 K. Single crystals of both compounds were grown hydrothermally from Ag2O and Bi2O3 at 620 K and at oxygen pressures of 10 MPa. The crystal structure determination (Ag3BiO3: I41, a = 14.1924(1), c = 8.7997(1) Å, Z = 16, 1 729 diffractometer data, Rw = 0.057; Ag5BiO4: P21/n, a = 5.855(1), b = 8.984(1), c = 12.457(1) Å, β = 91.49(1)Å, Z = 4, 2716 diffractometer data, Rw = 0.036) shows that in Ag5BiO4 bismuth approximately has a square pyramidal coordination by five oxygen atoms. Two such pyramids share an edge thus forming ‘isolated’ Bi2O810? anions. In Ag3BiO3 the same groups are linked by the terminal oxygen atoms to form a three dimensional network. In both structures the cation arrangements form variants of the Laves-phases MgCu2 with silver occupying the copper positions. The Mg positions are ordered occupied by bismuth and silver.  相似文献   

11.
K3MnH5, the First Salt-like Manganese Hydride K3MnH5 and K3MnD5 were synthesized by the reaction of potassium hydride (deuteride) with manganese powder under a hydrogen pressure above 3000 bar at 875 K. X-ray investigations on powdered samples and elastic neutron diffraction experiments on the deuterated compound at the time-of-flight spectrometer LAD in the temperature range 5–600 K led to the complete structure determination. The atomic arrangement is isotypic with that of Cs3[CoCl4]Cl (space group: 14/mcm, Z = 4). The structure of K3MnH5 contains isolated [MnH4]2?-tetrahedra and additional hydrogen ions which are exclusively coordinated by potassium cations. The magnetic susceptibilities show Curie-Weiss behaviour. At temperatures below 50 K there are obviously antiferromagnetic interactions.  相似文献   

12.
Ternary Intermetallic Phases of Lithium, Transition Metals of the 4th Group and Elements of the 5th Maingroup with Statistical Metal Distribution in the ?Cation”?-Substructure The results of X-ray investigations and neutron diffraction on new and in some cases already known [1, 2] ternary intermetallic phases of Lithium with transition metals of the 4th group (b) and those of the 5th main group (X = P, As, Sb, Bi) will be reported. They crystallize in a partly ?filled”? antifluorite type structure with a statistical Li/B-distribution in the tetrahedral sites. The structures are obviously stabilized by small amounts of enclosed d-elements.  相似文献   

13.
Synthesis and Structure of the Ternary Ammonium Nitrates (NH4)2[M(NO3)5] (M = Tb? Lu, Y) Single crystals of the ternary ammonium nitrates (NH4)2[M(NO3)5] (M = Tb? Lu, Y) are obtained from the solution of the sesquioxides in a melt of NH4NO3 and sublimation of the excess NH4NO3. In the crystal structure of (NH4)2[Tm(NO3)5] (trigonal, P31, Z = 3; a = 1 123.76(8), c = 930.1(1) pm; R = 0.062; Rw = 0.034) Tm3+ is surrounded by five bidentate nitrate ligands. The isolated [Tm(NO3)5]2? groups are held together by ammonium ions.  相似文献   

14.
Structures with AlB2- and CeMg2Si2-Type Units. The Compounds Eu3Pd4As4, Ca4Pd5P5, and Ca5Pd6P6 The new compounds Eu3Pd4As4, Ca4Pd5P5, and Ca5Pd6P6 (space groups and lattice constants see ?Inhaltsübersicht”?) have been prepared by heating mixtures of the elements. Their structures were determined by means of single-crystal X-ray methods and contain exclusively units, which are characteristic for the AlB2- and CeMg2Si2-type. The non-metal atoms are isolated from each other or connected to pairs; the ratio between these two kinds can be interpreted by ionic splittings of the formulas.  相似文献   

15.
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   

16.
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   

17.
Crystal Structures and Spectroscopic Investigations of Ternary CuII-Complexes with Bicyclic Dicarboxylic Acids and N,N-Donor Ligands The synthesis of coordination compounds [CuLdam] · 3H2O (H2L = 7-oxa-bicyclo[2.2.1]heptane-2-exo,3-cis-dicarboxylic acid ( 1 ) and its 1-methyl-derivative ( 2 ); dam = ethylendiamine, 1,2- and 1,3-propylendiamine, 2,2′-dipyridyl, 1,10-phenanthroline) has been described. Results of visible and IR spectroscopy and magnetic data are given. In the result of X-ray analyses of [CuL1dipy] · 3H2O ( 1 d ) and [CuL2en] · 3H2O ( 2 a ) the dicarboxylate anions of 1 and 2 proved to be tridentate chelating ligands. In 1 d the Cu atom has an approximately square-pyramidal coordination with the bridging O atom in the apical position. In 2 a , however, the coordination number is extended to six by an O atom of a second [CuL2en] unit resulting in a centrosymmetric complex dimer with octahedrally coordinated Cu atoms. The water molecules do not participate in the coordination of the Cu atoms and form a complicated system of hydrogen bonds in the crystal.  相似文献   

18.
Ba8Cu16P30 – a New Ternary Variant of the Clathrate I Type Structure Ba8Cu16P30 (a = 14.117(1) Å, b = 10.093(1) Å, c = 28.022(2) Å) was prepared by heating a mixture of the elements (800°C; excess of Ba and P; removal of the by-products by acetic acid/H2O2). The compound crystallizes orthorhombically (Pbcn; Z = 4) in a new superstructure of the cubic clathrate I type structure with an ordered distribution of the atoms. The structure is characterized by a three-dimensional framework of CuP4 tetrahedra with cavities in the form of pentagonal dodecahedra and tetrakaidecahedra, which are occupied by the Ba atoms. The compound shows semiconduction, therefore the composition should be Ba8Cu15.5P30.5.  相似文献   

19.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

20.
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