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1.
Transport numbers for potassium and rubidium cations in solid electrolytes (K1 – x Rb x )3.8M0.1P2O7(M = Ca, Cd, Ba) are measured, and the co-cation nature of the electrolytes" conduction is confirmed. The concentration dependences of transport numbers are used to draw a conclusion about the ratio between mobilities of potassium and rubidium cations. The presence of an extremum in the concentration dependence of the activation energy for the rubidium-cation constituent of conduction is confirmed by the NMR method. The obtained results are explained by assuming that the polyalkaline effect is largely due to an ordering of mobile alkali cations.  相似文献   

2.
Abstract

Infrared and Raman spectra of dipotassium zinc bis(dihydrogendiphosphate) dihydrate, K2Zn(H2P2O7)2 .2H2O have been collected and interpreted using factor group analysis. Noncoincidence of the Raman and infrared spectra bands confirms a centrosymmetric structure for K2Zn(H2P2O7)2 .2H2O previously investigated by X-ray structural study, as well as the joint appearance of νas POP and νs POP point to a bent POP configuration.  相似文献   

3.
Zusammenfassung Einkristalle von GeP2O7 werden hergestellt und röntgenographiert. Die Elementarzelle erweist sich, entgegen einer früheren Annahme1, als kubisch, jedoch mita=22,854Å, und entspricht somit der 27fachen Zelle von ZrP2O7 nach dem Strukturvorschlag vonG. R. Levi undG. Peyronel 2. Auf Diffraktometeraufnahmen werden auch für die analogen Verbindungen mit Si, Sn, Pb, Ti, Zr, Hf, Th und U zusätzlich sehr schwache Reflexe nachgewiesen, welche durch die gegenüber der einfachen Zelle niedrigere Symmetrie hervorgerufen werden. Danach besitzen offensichtlich alle Verbindungen Me(IV)P2O7 die große Zelle; die in der Literatur angegebenen Werte für die Gitterkonstante beziehen sich daher auf die Unterzelle. Bei CeP2O7 lassen sich wegen ungenügender Homogenität und mäßig kristallimen Zustandes die Überstrukturlinien nicht beobachten. Die Zugehörigkeit zu den übrigen Vertretern (Isotypie) ist aber wahrscheinlich. Die vonL. M. Borlera undA. Burdese 3 für die Unterzelle von CeP2O7 und GeP2O7 angegebenen Gitterparameter können nicht bestätigt werden. Die 6er-Koordination von Silicium sowie die Winkelung der P-O-P-Bindung in der P2O7-Gruppe werden diskutiert. Die Existenz der Unterzelle in anderen Temperaturbereichen ist möglich.Mit 2 Abbildungen  相似文献   

4.
This article deals with the insoluble compounds, formed in CuSO 4 -(NH 4 ) 4 P 2 O 7 -H 2 O system. The solutions were analyzed by means of chemical analysis, the precipitate--by means of x-ray diffraction, chemical and thermal analysis, and FTIR spectroscopy. We have established that at least three poorly soluble compounds can form in the system CuSO 4 -(NH 4 ) 4 P 2 O 7 -H 2 O. Their chemical formulae are Cu 2 P 2 O 7 ;5H 2 O and polymorphic Cu 3 (NH 4 ) 2 (P 2 O 7 ) 2 ;3H 2 O. The first modification is most stable when |Cu + P 2 O 7 | = 0.25 M ( n = 1.0), and, in a matter of days, Dimorph A transforms to Dimorph B, which has not been described in any publications.  相似文献   

5.
低温水热合成是水热化学一个活跃的研究方向,在氧化物粉末的合成方面具有潜在的应用价值.La2M2O7(M=Ti,Zr)陶瓷材料的优良特性使其多晶粉末的合成倍受关注[1,2].  相似文献   

6.
Summary Crystals of Co2(X 2O7)·2H2O,X=P/As were synthesized under hydrothermal conditions. Their crystal structures were determined by single crystal X-ray diffraction:a=6.334(1)/6.531(2),b=13.997(2)/14.206(4),c=7.637(1)/7.615(2)Å, =94.77(2)/94.74(2)°, space group P21/n,R=0.032/0.046,R w=0.028/0.034 for 2423/2042 reflections and 131/119 variables. Within the twoXO4 tetrahedra connected via a common corner to anX 2O7 group the average P-O bond lengths are approximately equal (1.540 and 1.543 Å), but As-O differs significantly (1.685 and 1.696 Å). A comparison with the isotypic Mn and Mg pyrophosphates shows a correlation between the ratio Me-O/X-O and the angle O-X-O.
Vergleich der Kristallstrukturen von Co2(X 2O7)·2H2O,X=P und As
Zusammenfassung Kristalle von Co2(X 2O7)·2H2O,X=P/As wurden unter Hydrothermalbedingungen synthetisiert. Ihre Kristallstrukturen wurden mittels Röntgenbeugung an Einkristallen bestimmt:a=6.334(1)/6.531(2),b=13.997(2)/14.206(4),c=7.637(1)/7.615(2) Å, =94.77(2)/97.74(2)°, Raumgruppe P21/n,R=0.032/0.046,R w=0.028/0.034 für 2423/2042 Reflexe und 131/119 Variable. In den beiden über eine gemeinsame Ecke zuX 2O7-Gruppen verknüpftenXO4-Tetraedern sind die mittleren P-O-Abstände ungefähr gleich (1.540 und 1.543 Å), hingegen differiert As-O signifikant (1.685 und 1.696 Å). Ein Vergleich mit den isotypen Mn- und Mg-Pyrophosphaten zeigt eine Korrelation zwischen dem Quotienten Me-O/X-O und dem WinkelX-O-X.
  相似文献   

7.
The bis(cyclopropylammonium)dihydrogenodiphosphate monohydrate is a new diphosphate associated with the organic molecule C3H5NH2. We report the chemical preparation and the crystal structure of this organic cation diphosphate. (C3H5NH3)2H2P2O7.H2O is orthorhombic (S.G. : P212121), with Z = 4 and the following unit-cell parameters : a = 4.828(1) Å, b = 11.011(1) Å, c = 25.645(2) Å. The P2O7 groups and H2O water molecules form a succession of bidimensional layers perpendicular to the c axis. The organic cations ensure the three-dimensional cohesion by NH-O hydrogen bonds.  相似文献   

8.
The composition and structure of (M,Cu)(Sr,Ln)2(Ln,Ca,Sr)Cu2O8– phases, where M = B, Al, Cr, Pb, Bi, Ru, or Mo (1212 type), and (M,Cu)(Sr,Ln(2(Ln,Ce4+)2Cu2O10– phases, where M = V, Cr, Mn, Ru, or Mo (1222 type), have been determined. The role of the M cation in the formation of the crystal structures and the superconductivity phenomenon was analyzed. The relationship between the type of M cation and structural parameters was discovered.  相似文献   

9.
The complexes [Cd(H2O)6](C5HN2O6)2 · 2H2O (I) and [Co(H2O)6](C5HN2O6)2 · 2H2O (II) were obtained in the crystalline state by reactions of cobalt chloride and cadmium chloride with ammonium 4-nitro-2,3,5,6-tetraoxopyridinate, (NH4)2 · (C5HO6N2)2. Their cocrystallization gave the heterometallic complex [Cd0.32Co0.68(H2O)6](C5HN2O6)2 · 2H2O (III). The crystal and molecular structures of complexes I-III were determined by X-ray diffraction. It was demonstrated that the complexation reactions occur by replacement of two ammonium cations 4-nitro-2,3,5,6-tetraoxopyridinate by the complex cations [M(H2O)6]2+. The tetraoxopyridinate anions and the complex cations are hydrogen-bonded through the coordinated and crystallization water molecules as well as through the O atoms of the organic anion. The thermolysis of complexes I and II was examined by TGA.  相似文献   

10.
The crystal structure determination of the title compounds showed that they are isomorphous, revealing the general formula [M(H2O)4(py)2](sac)2·4H2O. Their structures are built up of [M(H2O)4(py)2]2+ cations, saccharinato anions and non-coordinated water molecules. The metal atom lies on the inversion center and is octahedrally coordinated by four water oxygens and two pyridine nitrogen atoms. The crystal structure packing is achieved through the hydrogen bonds of Ow⋯Ow, Ow⋯O and Ow⋯N type. Coordinated water molecules are hydrogen bonded to non-coordinated ones at the same time participating in hydrogen bonding with carbonyl oxygen and nitrogen atom from the saccharinato anions. Non-coordinated water molecules participate in hydrogen bonding with the oxygen atoms belonging to the saccharinato CO and SO2 groups. The hydrogen bond network between the oxygen atoms belonging to the SO2 group of the saccharinato anions and one of the non-coordinated water molecules (OW3) constructs the centrosymmetric cavity in the structure.  相似文献   

11.
《Solid State Sciences》2000,2(4):489-493
The partial system Mg3(PO4)2Mg4Na(PO4)3Na4P2O7Mg2P2O7 in the ternary system MgONa2OP2O5 was investigated using thermal and X-ray diffraction analyses and microscopy, and its phase diagram has been determined. In this range of composition, two binary phosphates occur: Mg4Na(PO4)3 and Mg6Na8(P2O7)5. The former melts incongruently (at 1155°C) and the latter does congruently (at 808°C). In the partial system of interest, the two sections Mg4Na(PO4)3Mg2P2O7 and Mg4Na(PO4)3Mg6Na8(P2O7)5 are studied, and their phase diagrams are established. The partial system is divided into three partial ternary systems in which two ternary eutectics and one ternary peritectic occur.  相似文献   

12.
Fourteen bis(citrato)germanates(IV) and bis(citrato)stannates(IV) were prepared, in particular, [M(H2O)6][Ge(HCit)2] · 4H2O (M = Mg (I), Mn (II), Fe (III), Co (IV), Ni (V), Cu (VI), Zn (VII)) and [M(H2O)6][Sn(HCit)2] · nH2O (M = Mg, n = 4 (VIII); Mn, n = 2 (IX); Fe, n = 4 (X); Co, n = 4 (XI); Ni, n = 4 (XII); Cu, n = 4 (XIII); Zn, n = 3 (XIV)) (H4Cit is citric acid). The purity and the composition of the products were determined by a set of physicochemical methods including elemental analysis, thermogravimetry, and IR spectroscopy. The structures of I, II, IV, VI, VII, VIII, XI, and XII were determined by X-ray diffractometry. All eight crystals composed of centrosymmetrical octahederal [M(H2O)6]2+ cations, [Ge(HCit)2]2? (or [Sn(HCit)2]2?) anions, and crystal water molecules are isostructural. The structural units in I, II, IV, VI, VII, VIII, XI, and XII are connected by systems of hydrogen bonds to form a three-dimensional framework.  相似文献   

13.
许多化学工作者对单齿膦配体(PPh3,PBun3,PEt2Ph,P(OEt)3,P(OC6H5)3)与母体簇合物FeCo2(CO)9(μ3-S)的取代反应进行过详细研究[1-3],但对双齿膦配体与母体簇合物的取代反应研究报导较少.Aime[4]合成了含双齿膦配体的簇合物FeCo2(CO)7(μ3-S)(Ph2PCH2PPh2),并用13CNMR和IR光谱方法对其结构进行了表征.到目前为止,含双齿膦配体的该类簇合物的晶体与分子结构还未见报导.RosannaRossetti[2]通过研究母体簇合物与…  相似文献   

14.
The infrared (IR), Raman and 57Fe-M?ssbauer spectra of SrFe2(P2O7)2, BaFe2(P2O7)2 and PbFe2(P2O7)2 were recorded and discussed on the basis of the structural peculiarities of the compounds.  相似文献   

15.
合成了3个超分子化合物[M(4,4'-bipy)2(H2O)4]·(4,4'-bipy)2·(3,5-diaba)2·8H2O(M=Co(1),Ni(2),Cd(3);4,4'-bipy=4,4'-联吡啶;3,5-diaba=3,5-二氨基苯甲酸阴离子),用红外光谱、元素分析及X-射线单晶衍射进行了表征。3个化合物的晶体都属于单斜晶系,空间群为P2/c。晶体学参数:化合物1:a=0.9389(2)nm,b=0.7751(1)nm,c=3.9284(6)nm,β=90.14(2)°,V=2.85880(69)nm3,Z=4,Dc=1.397g·cm-3,F(000)=1266,μ=0.380mm-1,R1=0.0349,wR2=0.0829;化合物2:a=0.9383(2)nm,b=0.7753(1)nm,c=3.9218(6)nm,β=90.09(1)°,V=2.85280(68)nm3,Z=2,Dc=1.399g·cm-3,F(000)=1268,μ=0.420mm-1,R1=0.0366,wR2=0.0805;化合物3:a=0.94091(13)nm,b=0.77885(11)nm,c=3.9712(5)nm,β=90.10°,V=2.9102(7)nm3,Z=2,Dc=1.433g·cm-3,F(000)=1308,μ=0.454mm-1,R1=0.0468,wR2=0.0964。3,5-diaba未参与配位,在配位阳离子[M(4,4'-bipy)2(H2O)4]2 中,金属离子M髤与来自2个4,4'-bipy的2个氮原子和4个水分子的氧原子配位,呈八面体的几何构型。分子中还存在未配位的4,4'-bipy。通过配位阳离子、游离4,4'-bipy及未配位的3,5-diaba间的丰富氢键,构建成具有三维结构的超分子化合物。  相似文献   

16.
用水热法合成了3,5-二氨基苯甲酸与Nd(Ⅲ)的配合物Nd(C7H7N2O2)3(H2O)3(1),其结构经IR,元素分析和X-射线单晶衍射仪表征。1为单核结构,属六方晶系,R3空间群,晶胞参数:a=1.887 29(18)nm,b=1.887 29(18)nm,c=0.603 53(12)nm,β=90,°γ=120°,V=1.861 7(4)nm3,Z=3,μ=2.154 mm-1,Dc=1.744 g.cm-3,R1=0.014 3,wR2=0.033 2。1中Nd(Ⅲ)与来自3个3,5-二氨基苯甲酸的6个氧原子及3个配位水的氧原子进行配位,形成9配位化合物。  相似文献   

17.
CIONO2与O(3P)的反应机理   总被引:1,自引:0,他引:1  
采用密度泛函方法B3LYP/6-31G^*研究了反应O(^3P)+ClONO2→ClO+NO3反应O(^3P)+ClONO2→O2+ClONO的反应机。该结果与大部分实验者的推论是一致的,对于后一反应,其两种反应途径的活化势垒较为相近,表明两种反应途径均是可能的。  相似文献   

18.
ClONO2与O(3P)的反应机理   总被引:1,自引:0,他引:1  
采用密度泛函方法B3LYP/6-31G研究了反应O(~(3)P)+CIONO_2→CIO+NO_3和反应O(~(3)P)+ CIONO_2→O_2+ CIONO的反应机理.从动力学角度考察,计算结果表明,由于前一反应的活化势垒较低,因而是主要反应.该结果与大部分实验者的推论是一致的,对于后一反应,其两种反应途径的活化势垒较为相近,表明两种反应途径均是可能的.  相似文献   

19.
The ternary system YPO4Ca3(PO4)2Ca2P2O7 has been investigated by differential thermal analysis, powder X-ray diffraction, and microscopy in reflected light. Its phase diagram and isothermal section at room temperature have been determined. The system contains only one double phosphate which is formed at the 1:1 molar ratio YPO4:Ca3(PO4)2, i.e., Ca3Y(PO4)3.  相似文献   

20.
Two organic–inorganic compounds based on Keggin building blocks have been synthesized by hydrothermal methods, (C7N2H7)3(C7N2H6)?·?PMo12O40?·?2H2O (1) and (C7N2H7)3(C7N2H6)2?·?AsMo12O40?·?3H2O (2) (C7N2H6?=?benzimidazole). Single-crystal X-ray analysis revealed that 1 crystallized in the triclinic system, P-1 space group with a?=?9.8980(4)?Å, b?=?11.2893(4)?Å, c?=?25.8933(9)?Å, α?=?93.307(2)°, β?=?90.630(2)°, γ?=?108.330(2)°, V?=?2740.68(18)?Å3, Z?=?2, R 1(F)?=?0.0740, ωR 2(F 2)?=?0.1511, and S?=?1.037; 2 crystallized in the triclinic system, P-1 space group with a?=?12.3353(4)?Å, b?=?13.2649(4)?Å, c?=?20.2878(6)?Å, α?=?95.6630(10)°, β?=?100.1720(10)°, γ?=?99.3940(10)°, V?=?3195.72(17)?Å3, Z?=?2, R 1(F)?= 0.0329, ωR2 (F 2)?=?0.1236, and S?=?1.088. The two compounds show a layer framework constructed from Keggin-polyoxoanion clusters and benzimidazole via hydrogen bonds and π–π stacking interactions, resulting in a 3-D supramolecular network. Both have high catalytic activity for oxidation of methanol. When the initial concentration of the methanol is 5.37?g?m?3 in air and the flow velocity is 4.51?mL?min?1, methanol is completely eliminated at 150°C for 1 (160°C for 2).  相似文献   

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