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1.
The MCl/AlCl3/SO2 Systems (M = Li, Na, K, NH4) Phase diagrams of the ternary systems of the type MCl/AlCl3/SO2 were determined by measurement of SO2 pressure, solubilities, and by thermal analysis. The complete phase diagram in the range from ?30 to +50°C is given for the case M = Na, partial diagrams for M = Li, K, NH4. There exist solid compounds of the type MAlCl4 · nSO2 (M = Li, Na; n = 1.5 and 3) (M = K; n = 1.5 and 5) (M = NH4; n = 5). Liquid phases can be obtained at room temperature and atmospheric pressure in the NaCl or LiCl containing systems.  相似文献   

2.
Crystal Structure, Conductivity, and Magnetic Susceptibility of Er2Te3 Via a chemical vapour transport reaction with ErCl3 as transporting agent, single crystals of Er2Te3 up to a size of 1.5 mm are available. X-ray structure analysis revealed for the compound the Sc2S3-type with the space group Fddd and the lattice parameters a = 1212.7(2) pm, b = 858.1(2) pm and c = 2572.8(4) pm (Z = 16). According to measurements of the fundamental absorption (DRIFT) the compound is a semiconductor with a band gap of 0.77(5) eV. Magnetic susceptibility measurements revealed paramagnetic behaviour in the temperature range 5–300 K with μp = 9.07 B.M. and θp = –4.3 K.  相似文献   

3.
Crystal Structure and Electric Conductivity of Spinel-Type Li2–2xMn1+xCl4 Solid Solutions The electric conductivity of the fast lithium ion conductors Li2–2xMn1+xCl4 was measured by impedance spectroscopic methods. The conductivities obtained, e.g. ~ 4 × 10?1 Ω?2 cm?1 at 570 K, depend only little on the lithium content. The crystal structure of Li1.6Mn1.2Cl4 was determined by neutron powder and X-ray single crystal diffraction (space group Fd3 m, Z = 8, a = 1 049.39(6) pm, Rw = 1.4% on the basis of 170 reflections). The lithium deficient chloride crystallizes in an inverse spinel structure like the stoichiometric compound Li2MnCl4 according to the formula (Li0,8)[Li0,4Mn0,6]2Cl4 with vacancies ( ) at the tetrahedral sites. The decrease of the Moct? Cl distances with the increase of x reveals that the ionic radius of Mn2+ in chlorides is equal or even smaller than that of Li+ opposite to fluorides and oxides. The ? Cl distances of spinel type chlorides are 237 ( tet) and 274 pm ( oct), respectively. The mechanism of the ionic conductivity is discussed.  相似文献   

4.
RbHg2 and CsHg2 — Preparation, Crystal Structures, and Electrical Conductivities Preparation, crystal structures and electrical conductivities of the new compounds RbHg2 and CsHg2 are described. Both compounds form reddish-black, air sensitiv single crystals with a metallic lustre and crystallize isotypically to the orthorhombic KHg2 in the space group Imma (No. 74). The specific electrical resistivity of pressed powder pellets shows a metallic behaviour between 1.4 K and room temperature. From an analysis of crystal structures and electrical properties one can suggest a formula M+(Hg2)0e? to describe the chemical bonding in these compounds qualitatively.  相似文献   

5.
Ternary Halides of the A3MX6 Type. III [1, 2]. Synthesis, Structures, and Ionic Conductivity of the Halides Na3MX6 (X = Cl, Br) The bromides Na3MBr6 crystallize with the stuffed LiSbF6-type structure (type I; M = Sm? Gd) or with the structure of the mineral cryolite (type II; M = Gd? Lu). The structure types were refined from single crystal X-ray data (Na3SmBr6: trigonal, space group R3 , a = 740.8(2) pm, c = 1 998.9(8) pm, Z = 3; Na3YBr6: monoclinic, space group P21/n, a = 721.3(4) pm, b = 769.9(2) pm, c = 1 074.8(4) pm, β = 90.60(4)°, Z = 2). Reversible phase transitions from one structure to the other occur. The phase transition temperatures were determined for the bromides as well as for the chlorides Na3MCl6 (M = Eu? Lu). The refinement of both structures for one compound was possible for Na3GdBr6 (I: trigonal, space group R3 , a = 737.1(5) pm, c = 1 887(2) pm, Z = 3; II: monoclinic, space group P21/n, a = 725.2(1) pm, b = 774.1(3) pm, c = 1 080.1(3) pm, β = 90.76(3)°, Z = 2). All compounds exhibit ionic conductivity of the sodium ions which decreases with the change from type I to type II. The conductivity of the bromides is always higher when compared with the respective chlorides.  相似文献   

6.
Novel Fast Ion Conductors of the Type M MIIICl6 (MI = Li, Na, Ag; MIII = In, Y) The ternary chlorides Li3InCl6, Na3InCl6, Ag3InCl6, and Li3YCl6 have been studied by difference scanning calorimetry, high-temperature X-ray, infrared, and high-temperature Raman methods. Impedance spectroscopic measurements exhibit fast ionic conductivity increasing in the sequence Na3InCl6 < Li3YCl6 < Ag3InCl6 < Li3InCl6. In the range of 300°C, Li3InCl6 is the best lithium ion conductor known so far (σ = 0,2 Ω?1 cm?1 at 300°C). With the exception of Na3InCl6, the chlorides exhibit complicated order-disorder phase transitions.  相似文献   

7.
Synthesis and Crystal Structure of the Ternary Rare Earth Chlorides Na2MCl5 (M = Sm, Eu, Gd) Single crystals of Na2EuCl5 were obtained from the melt of NaCl and EuCl3 in a 2:1.2 molar ratio by slow cooling. It crystallizes in the orthorhombic crystal system (space group Pnma) with the structure of K2PrCl5 with a = 1 204.0(3) pm, b = 833.9(3) pm, c = 768.2(3) pm, Z = 4. Pure powder samples of the compounds Na2MCl5 (M = Sm? Gd) are available by heating mixtures of the binary components below the melting point.  相似文献   

8.
Contributions to the Properties of Titanates with Ilmenite Structure. II. Study on the Thermodynamics and the Electrical Conductivity of NiTiO3 and Other Phases with Ilmenite Structure NiTiO3 shows a phase transition at high temperatures (Tc = 1290°C). The standard enthalpy and entrop of the reaction NiO + TiO2 = NiTiO3 was estimated for temperatures above and below the transition temperature using emf-measurements based on the following solid state galvanic cell: Ni,TiO2, NiTiO3|ZrO2(+CaO)|Ni,NiO. The transition enthalpy was found to be 18 ± 2 kJmol?1, The transition entropy is 12 ± 1 JK?1mol?1. This is in good agreement with the calculated entropy change for an order-disorder transition (11.5 JK?1mol?1). The influence of other cations like Mg2+ and Co2+ on the transition temperature was investigated by measurements of the electrical conductivity as a function of composition. Ni1?xMgxTiO3 shows a strong shift of the transition to higher temperatures if a small part of the Ni2+ was replaced by Mg2+. A linear correlation between the temperature shift and the amount of Co2+ was found for Ni1?xCoxTiO3. Thermoanalytical investigations reveal an endothermic peak during the heating period some degrees below the melting point of CoTiO3. The substitution of Ge4+ for Ti4+ is without any influence on the transition temperature. By doping the NiTiO3 with Ga2O3, the anomalous increase of the electrical conductivity with temperature is shifted to lower temperatures.  相似文献   

9.
Ternary Halides of the A3MX6 Type. VI. Ternary Chlorides of the Rare-Earth Elements with Lithium, Li3MCl6 (M ? Tb? Lu, Y, Sc): Synthesis, Crystal Structures, and Ionic Motion Single crystal X-ray studies on the ternary chlorides Li3ErCl6, Li3YbCl6 and Li3ScCl6 show that they crystallize in three different structure types. Li3ErCl6 (trigonal, P3 ml, Z = 3, a = 1117.7(2); c = 603.6(2) pm; the chlorides with M ? Tb? Tm, Y are isotypic) and Li3YbCl6 (orthorhombic, Pnma, Z = 4, a = 1286.6(1); b = 1113.2(1); c = 602.95(8) pm; Li3LuCl6 is isotypic) have very similar structures that may be derived from hexagonal closest packings of chloride ions with the cations occupying octahedral holes in part statistically. Li3ScCl6 (monoclinic, C2/m, Z = 2, a = 639.8(1); b = 1104.0(2); c = 639,1(1) pm; β = 109.89(1)°) crystallizes isotypic with Na3GdI6 and Li3ErBr6, structures that may be derived from a cubic closes packings of anions. The ionic movement in Li3YCl6 and Li3YbCl6 has been investigated by impedance and 7Li-NMR spectroscopy.  相似文献   

10.
New Mixed‐Valence Ternary Bromides and Iodides of Dysprosium and Thulium of the Type A5M3X12 The new ternary mixed‐valence bromides and iodides of dysprosium and thulium Rb5Dy3Br12, Rb5Tm3Br12, K5Dy3I12, K5Tm3I12, Rb5Dy3I12 and Rb5Tm3I12 were obtained by metallothermic reduction of DyBr3, TmBr3, DyI3 and TmI3, respectively, with potassium and rubidium in the presence of the respective alkali metal halides in sealed niobium containers. The crystal structure was determined for the example of K5Dy3I12 (hexagonal, P 6 2m, Z = 1; a = 1446.7(2), c = 473.3(1) pm): DyI6 octahedra are connected via common trans edges to chains. Magnetic measurements on X‐ray pure samples show Curie‐Weiss behaviour at sufficiently high temperatures. Antiferromagnetic coupling occurs at low temperatures.  相似文献   

11.
The liquid-solid phase diagram of the binary systems AlPO4?M3PO4(M=Li, Na, K) have been established. The additional compounds Na3Al(PO4)2, Na3Al2(PO4)3 and K3Al2(PO4)3 have been found again. A new compound K3Al(PO4)2 is observed. The melting point of Na3PO4 is 1545°C and K3PO4 does not melt up to 1700°C.  相似文献   

12.
13.
The reactions of Au(OH)3, M2CO3 (M = Li, Na, Rb), and methanesulfonic acid at elevated temperatures in sealed glass ampoules lead to single crystals of M[Au(CH3SO3)4] (M = Li, Na, Rb). In the crystal structures of Li[Au(CH3SO3)4] (tetragonal, I$\bar{4}$ , Z = 2,a = 938.64(2) pm, c = 917.01(3) pm, V = 807.93(4) Å3) and Rb[Au(CH3SO3)4] (tetragonal, P$\bar{4}$ 21c, Z = 2, a = 946.7(1) pm,c = 889.9(1) pm, V = 797.6(2) Å3) the complex aurate anions are linked by the M+ ions in three dimensions. Contrastingly, in the structure of Na[Au(CH3SO3)4] (triclinic, P$\bar{4}$ , Z = 1, a = 540.04(2) pm,b = 863.75(2) pm, c = 973.29(3) pm, α = 72.694(2)°, β = 75.605(2)°, γ = 77.687(2)°, V = 415.05(2) Å3) the complex anions are connected into layers that are further connected by weak hydrogen bonds. The thermal decomposition of Li[Au(CH3SO3)4] was monitored up to 500 °C and leads in a multi‐step process to elemental gold and Li2SO4.  相似文献   

14.
Ternary Bromides and Iodides of Divalent Lanthanides and Their Alkaline-Earth Analoga of the Type AMX3 and AM2X5 Metallothermic reduction of the tribromides and -iodides MX3 (M = Sm, Dy, Tm, Yb) with alkali metals as well as with indium and thallium (A = Cs, Rb, K, In, Tl) results in most cases in ternary compounds with the composition AMX3 and AM2X5, respectively. Analogous compounds with M = Ba, Sr, Ca were synthesized from the binary components. The AMX3 compounds crystallize with the following types of structure: the perovskite-type and its distorted variants, the NaNbO3-II- and the GdFeO3-type, the NH4CdCl3- and the stuffed PuBr3-type. These structure types differ by a gain of condensation of the [MX6] octahedra (three-dimensional connection via corners within the variants of the perovskite-type, double chains of edge- and face-connected octahedra within the NH4CdCl3-type, and layers of corner- and edge-connected octahedra within the stuffed PuBr3-type of structure). This comes along with a reduction of the coordination number of A+ from 12 (“ideal” perovskite) to 8 + 2 (GdFeO3-type), 9 (NH4CdCl3-type), and 8 (stuffed PuBr3-type). Thus, the A/[MX6] size ratio determines which AMX3 type of structure is adopted. If the M2+ ion is large enough, ternary compounds with the composition AM2X5 occur either in addition to the AMX3 compounds or exclusively. They crystallize with the TlPb2Cl5 type of structure (C.N.(M2+) = 7 and 8). All of the AMX3 and AM2X5 compounds are summarized in a structure field diagram.  相似文献   

15.
Ternary Bromides of Aluminium, Gallium, and Indium of the Formula Type AIMIIIBr4 (AI = Na, Ga, K, In, Rb). An Overview The fourteen possible bromides AIMIIIBr4 with AI = Na, Ga, K, In, Rb and MIII = Al, Ga, In are obtained from mixtures of the binary components, ABr and MBr3. Six different structure types are observed: NaGaBr4-, NaAlCl4-, GaCl2-, β-GaBr2-, KAlBr4-, and BaSO4-type. Singlecrystal data are reported for the examples of NaGaBr4, KGaBr4, and InGaBr4. Without exception, slightly distorted tetrahedra [MBr4]? occur. The structural variety must be sought in the adjustment of the coordinational needs of the counter cations A+ (coordination numbers between six and twelve).  相似文献   

16.
Synthesis and Crystal Structure of (NH4)3Cu4Ho2Br13. Further Bromides of the (NH4)3Cu4M2Br13 Type (M = Dy? Lu, Y) and on Rb3Cu4Ho2Br13 Single crystals of (NH4)3Cu4Ho2Br13 were obtained for the first time from the reaction of CuBr with HoBr3 which was contaminated with NH4Br: cubic, space group Pn3 , Z = 2, a = 1101.71(5) pm. The crystal structure may be considered as a variant of the fluorite type according to [(HoBr6)4][(NH4)6(Cu4Br)2] ? Ca4F8. Pure products can be prepared from the binary halides in glass ampoules at 350°C. The bromides (NH4)3Cu4M2Br13 (M = Dy? Lu, Y) and Rb3Cu4Ho2Br13 are isotypic with (NH4)3Cu4Ho2Br13.  相似文献   

17.
On Ruthenium perovskites of type Ba2BRuO6 and Ba3BRu2O9 with B = Indium, Rhodium The black perovskites Ba2InRu5+O6 and Ba3InRu2O9 (mean oxydation state of ruthenium: +4.5) adopt the hexagonal BaTiO3 structure and form a continuous series of mixed crystals. According to the intensity calculations and analysis of the vibrational spectroscopic data an ordered distribution between indium and ruthenium is present: 1:1 order in Ba2InRuO6 (space group P3 m1 ? D; R′ = 5.3%); 1:2 order in Ba3InRu2O9 (space group P63/mmc ? D; R′ = 4.6%). The corresponding black Rh compounds, Ba2RhRuO6 and Ba3RhRu2O9, crystallize in the rhombohedral 9 L type of BaRuO3.  相似文献   

18.
Formation and Characterization of Surface Compounds in the Systems (C6H5CH2)4M/γ-Al2O5 (M = Ti, Zr) By O-bridges anchored surface-compounds are formed by protolytic splitting off of benzyl groups if tetrabenzyltitanium and -zirconium are added to γ-alumina. These compounds contain the metal in different oxidation states in dependence on the carrier/substrate ratio and the density of OH groups on the alumina surface. The different kinds of surface compounds are discussed. Furthermore, the products formed by thermal decomposition and hydrogenolysis of the surface compounds were analysed. With regard to catalytic conversion reactions of hydrocarbons systems of the type (C6H5CH2)4M/Pt/γ-Al2O3were involved in the investigations.  相似文献   

19.
Vibrational Spectra of Solid, Liquid, and Soluted Metal Polysulphides. II Polysulphides Rb2Sn (n ? 4) and Na2S4 All compounds have been prepared from the elements in liquid ammonia. Whereas Rb2S4 has no defined composition, the vibrational spectra of Cs2S4 and their structure similar to Na2S4 indicate that Cs2S4 is a well-defined compound in contrast to former suggestions. Rb2S5 and Cs2S6 are the members with the greatest chainlength of their homologe series. While Na2S4 still exists of S42? chains in the melt the other polysulhpides disproportionate to S3? radicals and probably monosulphide. In the melt of Cs2S6, quenched to room temperature, a double branched chain structure, the thio-analogue of dithionite, S2S42?, is suggested. All polysulphides have a mean valence frequency, which is independent of the cation and decreases with increasing chainlength.  相似文献   

20.
Compounds A3M5 (A = alkaline earth, M = triel/tetrel): A Case Study on Structural and Electronic Factors Stabilizing Polar Intermetallics Starting from the non electron precise binary compounds Ca3Ga5/Sr3In5 (Hf3Ni2Si3 type) and Ba3Al5 at one hand and Ba3Pb5 (Pu3Pd5 type) at the other hand, a series of new ternary intermetallics of the general formula A3M5 (A: alkaline earth, M: triel/tetrel) has been synthesized, structurally characterized and studied by band structure calculations. The chemical substitution of M in A3M5 allows, via the continous variation of the radius ratio (rA:rM) and the valence electron number (VE/M) the detection of the geometrically and electronically determined stability ranges of the three structure types formed by the binary compounds. At values of rA:rM between 1.30 and 1.52 in the triel rich region of A3M′xM″5?x the Hf3Ni2Si3 type (orthorhombic, space group Cmcm) is formed: In Ca3Ga5 up to 1.8 Ga can be substituted by Al, in Sr3In5 similar amount of In can be replaced by either Al or Ga. The mixed trielide Sr3Al2.6Ga2.4 (a = 468.4(1), b = 1132.5(1), c = 1570.0(2) pm, R1 = 0.0261) can be obtained, although both corresponding binary phases are not known. At larger values of the ratio rA/rM as in Ba3Al3Ga2 (Ba3Al5 type, hexagonal, space group P63/mmc, a = 598.9(1), c = 1456.0(3) pm, R1 = 0.0353) layers of condensed M5 building blocks with Al‐Al partial bonds are formed. Substituting one In position in Sr3In5 against Pb results in the isotypic, but electron precise Zintl compound Sr3In4Pb (a = 506.1(1), b = 1191.8(3), c = 1650.2(4) pm, R1 = 0.0286), where the Fermi level in shifted into a distinct minimum of the density of states. Conversely, at the tetrele rich end of the series A3InxPb5?x, characterized by compounds of the Pu3Pd5 type (orthorhombic, space group Cmcm) with almost isolated nido clusters M5, a minimum of the DOS can be reached, if Pb is partially substituted by In (A3InxPb5?x with A = Sr/Ba: x = 0.7/0.6; a = 1084.6(2)/1118.6(2), b = 867.1(2)/904.4(1), c = 1104.8(2)/1133.9(2) pm, R1 = 0.0394/0.0434).  相似文献   

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