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1.
New Oxoterbates(IV) with Lithium: On Rb2Li14[Tb3O14] and Li6Tb2O7 For the first time we prepared Rb2Li14[Tb3O14] as yellow single crystals from Li8TbO6 and Rb2O (Tb:Rb = 1:2) [Ag-cylinder, 500°C, 30 d, then Au-tube, 700°C, 27 d]. The structure refinement [652 I0 (h kl), four circle diffractometer Philips PW 1100, ω-scan, MoKα, R = 4.69%, Rw = 3.24%, absorption considered, Immm with a = 1 283.07(10), b = 790.87(7), c = 736.87(7)pm, Z = 2, dx = 4.30 g · cm?3] confirms that it is isotypic with K2Li14[Pb3O14]. Furthermore we got for the first time Li6Tb2O7 as a bright yellow compound from Li2O2 and “Tb4O7*” [(Li:Tb = 3.4:1), Au-ube, 750°C, 13 d (powder), 850°C 22 d (single crystals)] and by thermal decomposition of Rb2Li14[Tb3O14] (Au-tube, 850°C, 25 d). Powder and single crystal data [1 327 I0 (h kl), four circle diffractometer PW 1100, ω-scan, AgKα, R = 9.38%, Rw = 5.23%, absorption not considered, P21/a, a = 1 056.30(10), b = 613.50(4), c = 546.56(5) pm, β = 109.668(7)°, Z = 2, dx = 4.67 g · cm?3 dpyc = 4.53 g · cm?3] reveal a new type of structure that may be deduced by the NaCl-type of structure. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.  相似文献   

2.
Reaction of (CH3)2 Te with CF3I: Preparation and Properties of [(CH3)2TeCF3]I The irradiation of a mixture of (CH3)2 Te and CF3I at low temperature yields [(CH3)2TeCF3]I. From the thermal decomposition as well as in polar solvents CH3TeCF3 and CH3I are formed. Attempts to prepare bis- or tris(trifluoromethyl)tellurium compounds from these reactions failed. [(CH3)2TeCF3]I reacts with salts or acids to form many new derivatives of the composition [(CH3)2TeCF3]X (X = Cl, NO3, 1/2 SO4, OCOCH3, OCOCF3, B(C6H5)4, OC6H2(NO2)[3].  相似文献   

3.
Inhaltsübersicht. Erstmals wurden klar durchscheinende, orange-farbene Einkristalle von Cs2Li14[Tb3O14] aus Cs2TbO3 und Li2O (Tb: Li = 1:5) dargestellt [550°C, 21 d, verschlossenes AuRohr]. Es liegt der K2Li14[Pb3O14]-Typ vor [Vierkreisdiffraktometerdaten, PW 1100, MoKä-Strahlung, 660 Io(hkl), R = 4,8%, Rw = 3,4%, Immm, a = 1293,5(8), b = 792,6(3), c = 740,4(3) pm, Z = 2, d = 4,65]. Ebenfalls neu wurde K2Li14[Zr3O14] in Form farbloser Einkristalle durch Tempern inniger Gemenge von K2O, Li2O und ZrO2 (K: Li: Zr = 1:4:1,5) dargestellt [900°C, 14 d, geschlossene Ni-Bombe] und röntgenographisch untersucht. Die Strukturverfeinerung [612 Io(hkl), Vierkreisdiffraktometerdaten, PW 1100, MoKα-Strahlung, R = 5,9%, Rw = 5,3%, Immm, a = 1244,6, b = 776,4, c = 724,3 pm, Z = 2] bestätigt die Isotypie mit K2Li14[Pb3O14]. Der Madelunganteil der Gitterenergie, MAPLE, Effektive Koordinationszahlen, ECoN, diese über Mittlere Effektive Ionenradien, MEFIR, wurden berechnet. Für die nun bekannten Vertreter dieses Typs wurde ein Isotypievergleich vorgenommen. New Compounds of the K2Li14[Pb3O14] Type: Cs2Li14[Tb8O14] and K2Li14[Zr3O14] For the first time Cs2Li14[Tb3O14] has been prepared as orange single crystals from Cs2TbO3 and Li2O (Tb: Li = 1:5) [550°C, 21 d, sealed Au-Tube]. Structure Refinement [four-circle diffractometer data, PW 1100, MoKα radiation, 660 Io(hkl), R = 4.8%, Rw = 3.4%, Immm, a = 1293.5(8), b = 792.6(3), c = 740.4(3) pm, Z = 2, d = 4.65] confirms isotypy with K2Li14[Pb3O14]. K2Li14[Zr3O14] has also been prepared as colorless single crystals from K2O, Li2O, and ZrO2 (K: Li: Zr = 1:4:1.5), [900°C, 14 d, closed Ni-cylinder] and investigated by x-ray [612 Io(hkl), four-circle diffractometer data, PW 1100, MoKα radiation, R = 5.9%, Rw = 5.3%, Immm, a = 1244.6, b = 776.4, c = 724.3 pm, Z = 2]. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, the latter derived from Mean Effective Fictive Ionic Radii, MEFIR, are calculated. A detailed comparison of the structures is carried out.  相似文献   

4.
As part of a continuing study of oxyfluorotellurates(IV), materials likely to present interesting nonlinear optical properties, two new phases, titanium(IV) tellurium(IV) trioxide difluoride, TiTeO3F2, and divanadium(IV) ditellurium(IV) heptaoxide difluoride, V2Te2O7F2, have been characterized and present, respectively, titanium and vanadium in the tetravalent state. The TiTeO3F2 structure is based on linear double rows of TiO3F3 polyhedra sharing vertices. These rows are connected to adjacent rows via two vertices of Te2O5 bipolyhedra. The Te, Ti, one F and two O atoms are on general positions, with one O and F statistically occupying the same site with half‐occupancy for each anion. One O and one F occupy sites with .m. symmetry. The V2Te2O7F2 structure consists of zigzag chains of VO4F2 octahedra alternately sharing O—O and F—F edges. These chains are connected via Te2O5 bipolyhedra, forming independent mixed layers. The Te, V, one F and three O atoms are on general positions while one O atom occupies a site of symmetry. In both phases, the electronic lone pair E of the TeIV atom is stereochemically active. A full O/F anionic ordering is observed in V2Te2O7F2, but in TiTeO3F2 one of the six anionic sites is occupied by half oxygen and half fluorine, all the others being strictly ordered. These compounds represent new members of a growing family of oxyfluorotellurates(IV), including the recently characterized members of formula MTeO3F, M being a trivalent cation. As was true for the previous members, they are characterized by an unusually high thermal and chemical stability in relation to the absence of direct Te—F bonds.  相似文献   

5.
The crystal structures of two new diphosphates, sodium hexamanganese bis­(diphosphate) triphosphate, NaMn6(P2O7)2(P3O10), and potassium hexacadmium bis­(diphosphate) triphosphate, KCd6(P2O7)2(P3O10), confirm the rigidity of the M6(P2O7)2(P3O10) matrix (M is Mn or Cd) and the relatively fixed dimensions of the tunnels extending in the a direction of the unit cell. The compounds are isomorphous; the P2O74? anion and the alkali metal cations lie on mirror planes. Bond‐valence analysis of the bonding details of the atoms found within the tunnels permits a prediction of the conductivity.  相似文献   

6.
IntroductionThesynthesisandsorptionpropertiesofopenframe worksolidssuchaszeolites1andmetalmolybdenumphos phate2 ,3withlargecavitiesprovokedenormousinterestbe causeoftheirpotentialapplicationincatalysis .One ,two andthree dimensionalsolidcompoundsconsistingo…  相似文献   

7.
The title compound, dilithium(I) trizinc(II) bis[diphosphate(4−)], is the first quaternary lithium zincopyrophosphate in the Li–Zn–P–O system. It features zigzag chains running along c, which are built up from edge‐sharing [ZnO5] trigonal bipyramids. One of the two independent Zn sites is fully occupied, whereas the other is statistically disordered by Zn2+ and Li+ cations, although the two Zn sites have similar coordination environments. Li+ cations occupy a four‐coordinated independent site with an occupancy factor of 0.5, as well as being disordered on the partially occupied five‐coordinated Zn site with a Zn2+/Li+ ratio of 1:1.  相似文献   

8.
9.
Single crystals of Na3Li(TiF6)2 were synthesized and studied by X-ray diffraction analysis (DAR-UMBk diffractometer, MoK radiation, graphite monochromator); space group P 21 c, a = 5.130(1), c = 18.046(4) Å. The structure was solved by the heavy-atom method and refined by the full-matrix least-squares method in anisotropic approximation to R = 0.053 and wR = 0.048 for 468 independent reflections with I > 3(I). The Madelung's constant for the lattice energy was calculated and the structure was compared to structures of other hexafluoro complexes of Group IV elements.  相似文献   

10.
11.
Li6Zr2O7 was obtained by annealing an intimate mixture of LiOH · H2O and freshly prepared ZrO2 in a stream of argon. It is monoclinic: C2/c, a = 1 044.5(1), b = 598.9(1), c = 1 020.0(1) pm, β = 100.26(1)°, Z = 4, R = 0.016 for 1 218 F values and 55 variables. The structure is closely related to that of NaCl with an ordered distribution of the metal atoms on the sodium sites while the oxygen atoms occupy seven eighths of the chlorine positions. Li has square pyramidal, Zr octahedral oxygen coordination. The corresponding Hf compound is isotypic: a = 1 040.2(1), b = 596,2(1), c = 1 015.0(1) pm, β = 100.36(1)°. 7Li nuclear magnetic resonance spectra of this compound give no indication for a high mobility of the Li+ ions.  相似文献   

12.
4-羟基吡啶-2,6-二甲酸铽配合物的制备及其晶体结构   总被引:2,自引:1,他引:2  
以丙酮和草酸二乙酯为原料 ,经过 3步反应合成了 4 羟基吡啶 2 ,6 二甲酸 (HDPA)。HDPA与硝酸铽在水溶液中反应 ,得到标题配合物 ;用X射线衍射法确定其晶体结构 ,分子式为Na3Tb(HDPA) 3·9H2 O ,属三斜晶系P 1空间群 ;晶胞参数 :a =1.10 3 9(5 )nm ,b =1.2 3 83(3 )nm ,c =1.42 5 3 (8)nm ,α =96.10° ,β =10 9.14°,γ =92 .810 (10 )° ,V =1.82 2 9(14 )nm3;Z =2 ;Dc=1.64 4g·cm- 3;μ =2 0 2 1mm- 1 ,R =0 .0 3 74,wR =0 .0 994。配合物较相应配位体吸收带变宽 (2 10~ 3 40nm) ,吸收峰位置出现明显红移 ,而且摩尔吸光系数都有所增加。 4 羟基吡啶 2 ,6 二甲酸铽配合物有很强的黄绿色特征荧光 ,荧光峰 491,5 43 ,5 82 ,62 0nm分别属于 5D4 →7F6 ,5D4 →7F5,5D4 →7F4 ,5D4 →7F3,发射带中最强的是 5D4 →7F5。  相似文献   

13.
Te(OH)6 · 2Na3P3O9 · 6H2O, is hexagonal (P63/m) with a = 11,67(1), c = 12,12(1) Å, Z = 2 and Dx = 2,225 g/cm3. Te(OH)6 · K3P3O9 · 2H2O, is monoklin (P21/c) with a = 19,61(5), b = 7,456(1), c = 14,84(6) Å, = 108,01(4), Z = 4 and Dx = 2,506 g/cm3. Both compounds are the first examples of phosphate tellurates in which the anion phosphate is condensed to the ring anion P3O9. As in phosphate tellurates already described the phosphate groups are independent of the TeO6 octahedra.  相似文献   

14.
The structure of [B6H9NaO14, H3BO3, 6H2O] was determined by single‐crystal X‐ray diffraction and further analyzed by FTIR spectroscopy and differential thermal/thermogravimetric analysis. The asymmetric unit contains Na–O polyhedra (distorted octahedron), [B6O8(OH)3] fundamental building blocks, one free water molecule and one free H3BO3 molecule. In the hexaborate anion, three B3O3 rings are linked by a common oxygen atom with five trigonal and one tetrahedral boron atoms. The hexaborate group is also linked to the oxygenated environment of the sodium atom by three other six‐membered rings, each of which involve two boron atoms, three oxygen atoms, and sodium as the joint atom.  相似文献   

15.
A new layered phosphate, Na7Y2(P2O7) 2(P3O10), containing both [P2O7]4? and [P3O10]5? groups, has been prepared. It crystallizes in the monoclinic space group P2/c with a = 16.205(4), b = 5.3746(9), c = 12.309(4) Å, β = 97.96(2)°, V = 1061.7(5) Å3 and Z = 2. The structure was solved and refined to R1 = 0.0298 and wR2 = 0.0698 for 1844 independent reflections with I > 2σ(I). It consists of layers of corner and edge-sharing YO7 polyhedra, P2O7 and P3O10 groups. Each layer is built up from two parallel [YP2O7] slabs, held together by the P3O10 groups. This arrangement gives rise to intersecting tunnels within the layer. The Na+ cations are located in the tunnels and between the layers. Both P2O7 and P3O10 groups contain unshared oxygen atoms directed toward the interlayer space and toward the tunnels. The P2O7 groups show a staggered configuration. In addition to this original layered framework, the title compound provides the third example of a compound containing a mixed anion of [P2O7]4? and [P3O10]5?. The structure was compared with the two previously reported ones, containing such a mixed anion: NH4Cd6(P2O7) 2(P3O10) [6] and Cs2Mo5O2(P2O7)3 · (P3O10) [7].  相似文献   

16.
17.
A new uranium(V) silicate, K3(U3O6)(Si2O7), and the germanate analogue, Rb3(U3O6)(Ge2O7), have been synthesized under high-temperature, high-pressure hydrothermal conditions and characterized by single-crystal X-ray diffraction. Their structures contain uranate columns formed of triple octahedral chains of the alpha-UF5 type linked by disilicate (or digermanate) units to form a 3-D framework structure. The valence state of uranium is confirmed by X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and magnetic susceptibility.  相似文献   

18.
《Solid State Sciences》2001,3(5):587-592
Two members of a new family of inorganic phosphates of general formula AIBII6(P2O7)2P3O10; KMn6(P2O7)2P3O10 (a=5.405(2), b=26.918(11), c=6.660(5), β=107.31(3)°, V=925.1(9) Å3, space group P21/m, Z=2, Dcalc=3.481 Mg m−3, R=0.0377 for 2235 observed reflections) and AgMn6(P2O7)2P3O10 (a=5.424(7), b=26.97(4), c=6.627(9), β=106.81(7)°, V=928(2) Å3, space group P21/m, Z=2, Dcalc=3.716 Mg m−3, R=0.0594 for 1577 observed reflections) have been synthesized and identified by single crystal X-ray diffraction. The isostructural complexes present an interesting comparison of silver and potassium bonding.  相似文献   

19.
Phase equilibria in the partial system Mg2P2O7?Na8Mg6(P2O7)5?NaPO3?Mg(PO3)2 were examined by differential thermal analysis and powder X-ray diffraction. It was found that there are six sections in the composition range under investigation.  相似文献   

20.
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