首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
Simultaneous TG-DTG-DTA studies on [Co(NH3)5Cl]Cl2 under non-isothermal conditions were carried out in dynamic air and argon atmospheres in the temperature range 293–1273 K. Thermogravimetric measurements under quasi-isothermal conditions were also made. On the basis of the experimental data (weight loss, X-ray diffraction, reflectance spectroscopy and chemical analysis), the probable decomposition sequences are presented. The data indicate that the thermal decomposition of [Co(NH3)5Cl]Cl2 occurs in three stages in argon and four stages in air.The changes in the morphology of crystalline [Co(NH3)5Cl]Cl2 powder in the course of its thermal decomposition in air were followed by scanning electron microscopy.
Zusammenfassung In dynamischer Luft- und ArgonatmosphÄre wurden im Temperaturbereich 293–1273 K unter nichtisothermen Bedingungen simultane TG-DTG-DTA Untersuchungen an [Co(NH3)5Cl]Cl2 durchgeführt, ebenso auch thermogravimetrische Untersuchungen unter quasi-isothermen Bedingungen. Auf der Grundlage der experimentellen Daten (Gewichtsverlust, Röntgendiffraktion, Reflexionsspektroskopie und chemische Analyse) wurde eine wahrscheinliche Zersetzungssequenz erstellt. Es zeigte sich, da\ die thermische Zersetzung in Argon in drei Schritten, in Luft dagegen in vier Schritten verlÄuftDie VerÄnderung der Morphologie kristallinen [Co(NH3)5Cl]Cl2-Pulvers im Verlaufe seiner thermischen Zersetzung in Luft wurde durch Scanning-Elektronenmikroskopie verfolgt.
  相似文献   

2.
The Structures of some Hexaammine Metal(II) Halides of 3 d Metals: [V(NH3)6]I2, [Cr(NH3)6]I2, [Mn(NH3)6]Cl2, [Fe(NH3)6]Cl2, [Fe(NH3)6]Br2, [Co(NH3)6]Br2 and [Ni(NH3)6]Cl2 Crystals of yellow [V(NH3)6]I2 and green [Cr(NH3)6]I2 were obtained by the reaction of VI2 and CrI2 with liquid ammonia at room temperature. Colourless crystals of [Mn(NH3)6]Cl2 were obtained from Mn and NH4Cl in supercritical ammonia. Colourless transparent crystals of [Fe(NH3)6]Cl2 and [Fe(NH3)6]Br2 were obtained by the reaction of FeCl2 and FeBr2 with supercritical ammonia at 400°C. Under the same conditions orange crystals of [Co(NH3)6]Br2 were obtained from [Co2(NH2)3(NH3)6]Br3. Purple crystals of [Ni(NH3)6]Cl2 were obtained by the reaction of NiCl2 · 6H2O and NH4Cl with aqueous NH3 solution. The structures of the isotypic compounds (Fm3 m, Z = 4) were determined from single crystal diffractometer data (see “Inhaltsübersicht”). All compounds crystallize in the K2[PtCl6] structure type. In these compounds the metal ions have high-spin configuration. The orientation of the dynamically disordered hydrogen atoms of the ammonia ligands is discussed.  相似文献   

3.
Metal Ampoules as Mini‐Autoclaves: Syntheses and Crystal Structures of [Al(NH3)4Cl2][Al(NH3)2Cl4] and (NH4)2[Al(NH3)4Cl2][Al(NH3)2Cl4]Cl2 The salts [Al(NH3)4Cl2]+[Al(NH3)2Cl4]–≡AlCl3 · 3 NH3 ( 1 ) and (NH4+)2[Al(NH3)4Cl2]+[Al(NH3)2Cl4]–(Cl–)2≡ AlCl3 · 3 NH3 · (NH4)Cl ( 2 ) have been obtained as single crystals during the reactions of aluminum and aluminum trichloride, respectively, with ammonium chloride in sealed Monel metal containers. The crystal structure of 1 was determined again [triclinic, P‐1; a = 574.16(10); b = 655.67(12); c = 954.80(16) pm; α = 86.41(2); β = 87.16(2); γ = 84.89(2)°], that of 2 for the first time [monoclinic, I2/m; a = 657.74(12); b = 1103.01(14); c = 1358.1(3) pm; β = 103.24(2)°].  相似文献   

4.
Preparation and Crystal Structure of (NH4)2[V(NH3)Cl5]. The Crystal Chemistry of the Compounds (NH4)2[V(NH3)Cl5], [Rh(NH3)5Cl]Cl2, and M2VXCl5 with M = K, NH4, Rb, Cs and X ? Cl, O (NH4)2[V(NH3)Cl5] crystallizes like [Rh(NH3)5Cl]Cl2 in the orthorhombic space group Pnma with Z = 4. The compounds are built up by isolated NH4+ or Cl? and complex MX5Y ions. The following distances have been observed: V? N: 213.8, V? Cl: 235.8–239.1, Rh? N: 207.1–208.5, Rh? Cl: 235.5 pm. Both structures differ from the K2PtCl6 type mainly in the ordering of the MX5Y polyhedra. The compounds M2VCl6 and M2VOCl5 with M = K, NH4, Rb, and Cs crystallize with exception of the orthorhombic K2VOCl5 in the K2PtCl6 type. The ordering of the MX5Y polyhedra in the compounds (NH4)2[V(NH3)Cl5], [Rh(NH3)5Cl]Cl2 and K2VOCl5 enables a closer packing.  相似文献   

5.
The values of the kinetic parametersE andA were determined by Kissinger's method on the basis of the DTA, DTG and DSC curves of particular stages of the thermal decomposition of [Co(NH3)6]2(C2O4)3· 4H2O in air and argon atmospheres. It is shown that the use of Kissinger's method for different kinds of experimental curves (DTA, DSC, DTG) leads to close results.
Zusammenfassung Für verschiedene Schritte der thermischen Zersetzung von [Co(NH3)6]2(C2O4)3· 4H2O in Luft bzw. Argon wurden nach dem Kissinger-Verfahren auf der Basis von DTA-, DTG- und DSC-Kurven Werte für die kinetischen ParameterE undA ermittelt. Es wurde gezeigt, daß das Kissinger-Verfahren für die verschiedenen Arten von experimentellen Kurven (DTA, DSC, DTG) genaue Ergebnisse liefert.
  相似文献   

6.
Binary complex salts of M(NH3)5Cl]2[IrCl6]Cl2 composition, where M = Co(III), Rh(III), or Ir(III), have been studied. All phases are isostructural with [M(NH3)5Cl]2[PtCl6]Cl2 complexes [M = Rh(III) and Ir(III)]; Xray structural and crystallochemical analysis have been performed.  相似文献   

7.
Single crystals of the organic‐inorganic arsenate(III): [(CH3)2NH2]3[As2Cl9] and [(CH3)2NH2][AsOCl2] have been grown from aqueous hydrochloric acid solution. The crystals [(CH3)2NH2]3[As2Cl9] have been investigated by X‐ray diffraction (at 253 K), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dilatometric and dielectric methods. They undergo two structural phase transitions of first order at 228/235 and 298/307 K (on cooling/heating), respectively, which are classified as an "order‐disorder" type. The trigonal [(CH3)2NH2]3[As2Cl9] structure (at 253 K, intermediate phase (II)) refined in the space group R3c, consists of isolated [As2Cl9]3‐ bioctahedral units and dimethylammonium cations hydrogen bonded to the bridging Cl atoms of the anions. The crystals of [(CH3)2NH2][AsOCl2] at 100 K are orthorhombic, space group Cmca. The structure contains one‐dimensional chains formed by strong distorted [AsO2Cl4] octahedra. The dimethylammonium cations reveal distinct disorder.  相似文献   

8.
Crystal Structures of the Hexachlorometalates NH4[SbCl6], NH4[WCl6], [K(18‐crown‐6)(CH2Cl2)]2[WCl6]·6CH2Cl2 and (PPh4)2[WCl6]·4CH3CN The crystal structures of the title compounds were determined by single crystal X‐ray methods. NH4[SbCl6] and NH4[WCl6] crystallize isotypically in the space group C2/c with four formula units per unit cell. The NH4+ ions occupy a twofold crystallographic axis, whereas the metal atoms of the [MCl6]— ions occupy a centre of inversion. There exist weak interionic hydrogen bridges. [K(18‐crown‐6)(CH2Cl2)]2[WCl6]·6CH2Cl2 crystallizes in the orthorhombic space group R3¯/m with Z = 3. The compound forms centrosymmetric ion triples, in which the potassium ions are coordinated with a WCl3 face each. In trans‐position to it the chlorine atom of a CH2Cl2 molecule is coordinated so that, together with the oxygen atoms of the crown ether, coordination number 10 is achieved. (PPh4)2[WCl6]·4CH3CN crystallizes in the monoclinic space group P21/c with Z = 4. This compound, too, forms centrosymmetric ion triples, in which in addition the acetonitrile molecules are connected with the [WCl6]2— ion via weak C—H···Cl contacts.  相似文献   

9.
Trans-[Cr(NH3)4(H2O)Cl]Cl2 (A) crystallizes in the monoclinic space group P21/m (No. 11) with a = 6.556(1), b = 10.630(5), c = 6.729(2) Å and β = 96.15(3)°. Trans-[Cr(NH3)4Cl2]I (B) has monoclinic C2/m (No. 12) space group and a = 9.877(2), b = 8.497(2), c = 6.047(2) Å and β = 108.98(2)°. Both unit cells contain two formula units. Cr? Cl, Cr? O(H2O) and three independent Cr? N(NH3) distances for A are 2.98(1), 2.023(2), 2.067(2), 2.086(3) and 2.064(3) °. Cr? Cl and Cr? N(NH3) bonds in B are 2.325(1) and 2.071(2) °. All octahedral angles are close to 90 and 180°. Both structures were refined to very low R values. Water molecule from trans-[Cr(NH3)4(H2O)Cl]2+ is hydrogen bonded to both ionic chlorides. Cation and two anions form the motive which repeats itself in the crystal. Cations and anions of the second structure are distributed in layers. Each cation and anion have coordination number eight.  相似文献   

10.
Preparation and Crystal Structure of (CH3NH3)8[NdCl6][NdCl4(H20)2]2Cl3 (CH3NH3)8[NdCl6][NdCl4 (H2O)2]2Cl3 is for the first time prepared and investigated by X-ray, single crystal work. It crystallizes in the monoclinic system (space group C2/m, Z = 2) with a = 9.358(5), b = 17.424(9), c = 15.360(8) Å, β = 108.30(4)°. The structure contains besides isolated Cl? ions distorted [NdCl6]3? octahedra and [NdCl4(H2O)2]? chains.  相似文献   

11.
Summary The solubility isotherms of the systems Cd(HCOO)2-CS(NH2)2-CH3OH and Cd-(CH3COO)2-CS(NH2)2-CH3OH have been investigated at 25°C. Reagents for the equilibrium existence of the salts Cd(HCOO)2, Cd(HCOO)2·2CS(NH2)2, CS(NH2)2, Cd(CH3COO)2, Cd(CH3COO)2·CS(NH2)2, and Cd(CH3COO)2·2CS(NH2)2 are found. The preparation of CdS by thermal decomposition of double salts and from saturated solutions by the dip technique are discussed.
Herstellung von CdS durch thermische Zersetzung von Doppelsalzen und gesättigten Lösungen der Systeme Cd(HCOO)2-CS(NH2)2-CH3OH und Cd(CH3COO)2-CS(NH2)2-CH3OH
Zusammenfassung Untersucht werden die Löslichkeitsisothermen der Systeme Cd(HCOO)2-Cs(NH2)2-CH3OH und Cd(CH3COO)2-CS(NH2)2-CH3OH bei 25 °C. Die Kristallisationsfelder der Salze Cd(HCOO)2, Cd(HCOO)2·2CS(NH2)2, CS(NH2)2, Cd(CH3COO)2, Cd(CH3COO)2·CS(NH2)2 und Cd(CH3COO)2·2CS(NH2)2 werden bestimmt. Die Herstellung von CdS durch thermische Zersetzung von Doppelsalzen und gesättigten Lösungen anhand des Tauchverfahrens wird diskutiert.
  相似文献   

12.
The thermal decomposition of [Co(NH3)5Cl]Cl2 was studied under non-isothermal conditions, in dynamic air and argon atmospheres. The kinetics of the particular stages of [Co(NH3)5Cl]Cl2 thermal decomposition were evaluated from the dynamic weight loss data by means of the modified Coats-Redfern method. TheD n andR n models were selected as the models best fitting the experimental TG curves. These models suggest that the kinetics and macromechanism of [Co(NH3)5Cl]Cl2 decomposition can be governed by diffusive and/or phase boundary processes. The values of the activation energy,E a, and the pre-exponencial factor,A, of the particular stages of the thermal decomposition were calculated.  相似文献   

13.
On the Crystal Structures of the Cyano Complexes [Co(NH3)6][Fe(CN)6], [Co(NH3)6]2[Ni(CN)4]3 · 2 H2O, and [Cu(en)2][Ni(CN)4] Of the three title compounds X‐ray structure determinations were performed with single crystals. [Co(NH3)6][Fe(CN)6] (a = 1098.6(6), c = 1084.6(6) pm, R3, Z = 3) crystallizes with the CsCl‐like [Co(NH3)6][Co(CN)6] type structure. [Co(NH3)6]2[Ni(CN)4]3 · 2 H2O (a = 805.7(5), b = 855.7(5), c = 1205.3(7) pm, α = 86.32(3), β = 100.13(3), γ = 90.54(3)°, P1, Z = 1) exhibits a related cation lattice, the one cavity of which is occupied by one anion and 2 H2O, whereas the other contains two anions parallel to each other with distance Ni…Ni: 423,3 pm. For [Cu(en)2][Ni(CN)4] (a = 650.5(3), b = 729.0(3), c = 796.5(4) pm, α = 106.67(2), β = 91.46(3), γ = 106.96(2)°, P1, Z = 1) the results of a structure determination published earlier have been confirmed. The compound is weakly paramagnetic and obeys the Curie‐Weiss law in the range T < 100 K. The distances within the complex ions of the compounds investigated (Co–N: 195.7 and 196.4 pm, Ni–C: 186.4 and 186.9 pm, resp.) and their hydrogen bridge relations are discussed.  相似文献   

14.
Zusammenfassung In Einkristallen von trans- [Cr en2 Cl2] Cl · HCl · xH2O und trans- [Co en2 Cl2] Cl · HCl · xH2O wurden die Kernquadrupolkopplungstensoren am komplex gebundenen und am ionischen Chlor mit der Methode der konstanten Frequenzen aus der magnetischen Kernresonanz bestimmt. Die Ergebnisse wurden zur Abschätzung des Ionencharakters der Metall-Halogen-bindung verwendet.
The nuclear quadrupole coupling tensor was determined for all chlorine nuclei in single crystals of trans-[Cr en2 Cl2] Cl · HCl · xH2O and trans- [Co en2 Cl2] Cl · HCl · xH2O from nuclear magnetic resonance data by the method of constant frequencies. The results were used to determine the approximate ionic character of the metal halogen bonds.
Résumé Appliquant la méthode des fréquences constantes aux résonances magnétiques nucléaires nous avons déterminé les tenseurs de couplage quadripolaire nucléaire du Cl complexé et ionique dans les monocristaux de trans- [Cr en2 Cl2] Cl · HCl · xH2O et trans- [Co en2 Cl2] Cl · HCl· xH2O. A l'aide des résultats le caractère ionique des liaisons métal-chlore est évalué.
  相似文献   

15.
The Crystal Structures of (NH4)2[ReCl6], [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN and [ReCl4(18)(Crown-6)] Brown single crystals of (NH4)2[ReCl6] are formed by the reaction of NH4Cl with ReCl5 in a suspension of diethylether. [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN crystallizes as brown crystal plates from a solution of ReCl5 in acetonitrile. Lustrous green single crystals of [ReCl4(18-crown-6)] are obtained by the reaction of 18-crown-6 with ReCl5 in a dichloromethane suspension. All rhenium compounds are characterized by IR spectroscopy and by crystal structure determinations. (NH4)2[ReCl6]: Space group Fm3 m, Z = 4, 75 observed unique reflections, R = 0.01. Lattice constant at ?70°C: a = 989.0(1) pm. The compound crystallizes in the (NH4)2[PtCl6] type, the Re? Cl distance is 235.5(1) pm. [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN: Space group P1, Z = 1, 2459 observed unique reflections, R = 0.12. Lattice dimensions at ?60°C: a = 859.0(1), b = 974.2(7), c = 1287.3(7) pm, α = 102.69(5)°, b? = 105.24(7)°, γ = 102.25(8)°. The structure consists of two symmetry-independent [ReCl2(CH3CN)4]+ ions with trans chlorine atoms, [ReCl6]2? ions, and included acetonitrile molecules. In the cations the Re? Cl bond lengths are 233 pm in average, in the anion they are 235 pm in average. [ReCl4(18-crown-6)]: Space group P21/n, Z = 4, 3 633 observed unique reflections, R = 0.06. Lattice dimensions at ?70°C: a = 1040.2(4), b = 1794.7(5), c = 1090.0(5) pm, b? = 108.91(4)°. The compound forms a molecular structure, in which the rhenium atom is octahedrally coordinated by the four chlorine atoms and by two oxygen atoms of the crown ether molecule.  相似文献   

16.
Thiochloro Anions of Molybdenum (IV). Crystal Structure of (NEt4)3[Mo3(μ3-S)(μ-S2)3Cl6]Cl μ CH2Cl2. Crystal Structure, Magnetic Properties, and EPR-Spectrum of (NEt4)2 [Mo2(μ-S2)(μ-Cl)2Cl6] From molybdenum pentachloride and tetraethylammonium hydrogensulfide in CH2Cl2 an insoluble product of composition (NEt4)2[Mo2S3Cl9] was obtained along with a brown solution, from which (NEt4)2[Mo2(S2)Cl8] was crystallized. The insoluble product and NEt4Cl react in CH2Cl2 to yield, among others, (NEt4)3[Mo3(S)(S2)3Cl6]Cl · CH2Cl2. The latter crystallizes in the orthorhombic space group Pnma, a = 2495.8, b = 1501.2, c = 1295.6 pm, Z = 4. According to the crystal structure determination (3070 observed reflexions, R = 0.049) the [Mo3(S)(S2)3Cl6]2? ion consists of an Mo3 triangle with Mo? Mo bonds, each side of the triangle is bridged by disulfido groups and one sulfur atom is capped over the Mo3 triangle; the single chloride ion is looseley associated to three S atoms. (NEt4)2[Mo2(S2)Cl8] also crystallizes in the space group Pnma, a = 1425.6, b = 1129.9, c = 2004.7 pm, Z = 4; structure determination with 1703 observed reflexions, R = 0.061. In the [Mo2(S2)Cl8]2? ion the Mo atoms are bridged via one disulfido group and two chlorine atoms. There is a Mo? Mo bond, but according to the magnetic properties and the EPR spectrum each Mo atom still possesses one unpaired electron.  相似文献   

17.
Anhydrous Lanthanum Acetate, La(CH3COO)3, and its Precursor, ·NH4)3[La(CH3COO)6] · 1/2 H2O: Synthesis, Structures, Thermal Behaviour Single crystals of (NH4)3[La(CH3COO)6] · ½ H2O are obtained by refluxing La2O3in (CH3COO)3 · 1.5 H2O with an excess of NH4CH3COO in methanol. The crystal structure (trigonal, R3 , Z = 6, a = 1 365.0(3) pm, c = 2 360(1) pm, R = 0.088, Rw = 0.061 exhibits the coordination number of nine for La3+, which is surrounded by three chelating-type bidentate and three unidentate acetate groups. Characteristic are monomeric units of [La(CH3COO)6]3? which are connected to a three-dimensional network by hydrogen bonds with the NH ions. Thermal decomposition consists of four steps with La(CH3COO)3, La2(CO3)3 and La2O2CO3 as intermediates and La2O3 as the final Product. Single crystals of La(CH3COO)3 are obtained from La2O3 in a melt of NH4CH3COO (molar ratio 1:12) in a sealed glass ampoule. The crystal structure (trigonal, R3 , Z = 18, a = 2 203.0(5) pm; c = 987.1(3) pm, R = 0.027, Rw = 0.023) shows the coordination number of ten for La3+. These are three-dimensionally connected by oxygen atoms of the acetate groups with two tetradentate double-bridging and one Z,Z-type-bridging bidentate acetate group.  相似文献   

18.
Preparation, Crystal Structure, Thermal Decomposition, and Vibrational Spectra of [Co(NH3)6]2[Be4O(CO3)6] · 10 H2O [Co(NH3)6]2[Be4O(CO3)6] · 10 H2O is a suitable compound for the quantitative determination of beryllium. It can be obtained by reaction of aqueous solutions of carbonatoberyllate with [Co(NH3)6]Cl3. The crystal structure (trigonal‐rhombohedral, R3c (Nr. 161), a = 1071,6(1) pm, c = 5549,4(9) pm, VEZ = 5519(1) · 106 pm3, Z = 6, R1(I ≥ 2σ(I)) = 0,037, wR2(I ≥ 2σ(I)) = 0,094) contains [Co(NH3)6]3+‐ and [Be4O(CO3)6]6–‐ions, which are directly hydrogen bonded as well as with water molecules. The complex cations and anions occupy the positions of a distorted anti‐CaF2‐type. The thermal decomposition, IR and Raman spectra are presented and discussed.  相似文献   

19.
Synthesis and Crystal Structures of (PPh4)2[In(S4)(S6)Cl] and (PPh4)2[In(S4)Cl3] InCl and PPh4Cl yield (PPh4)2[In2Cl6] in acetonitrile. This reacts with Na2S4 in presence of PPh4Cl, forming (PPh4)2[In(S4)(S6)Cl]. Its crystal structure was determined by X-ray diffraction (R = 0.075, 2 282 observed reflexions). It is isotypic with (PPh4)2[In(S4)(S6)Br] and contains anions with trigonal-bipyramidal coordination of In, Cl occupying an axial position, and the S4 and S6 groups being bonded in a chelate manner. The reaction of (PPh4)2[In2Cl6] and sulfur in acetonitrile yielded (PPh4)2[InCl5] and (PPh4)2[In(S4)Cl3]. The crystal structure analysis of the latter (R = 0.072, 4 080 reflexions) revealed an anion with distorted trigonal-bipyramidal coordination of In, the S4 group occupying one axial and one equatorial position; the S4 group shows positional disorder.  相似文献   

20.
The Chlorooxoarsenates(III) (PPh4)2[As4O2Cl10] · 2 CH3CN and (PPh4)2[As2OCl6] · 3 CH3CN (PPh4)2[As2Cl8] can be prepared from As2O3, SOCl2 and PPh4Cl in acetonitrile. Its oxidation with chlorine yields PPh4[AsCl6]. This was also obtained directly from arsenic, chlorine and PPh4Cl, (PPh4)2[As4O2Cl10] · 2 CH3CN being a side product; the latter was obtained with high yield from AsCl3, As2O3 and PPh4Cl in acetonitrile. By addition of PPh4Cl it was converted to (PPh4)2[As2OCl6] · 3 CH3CN. According to their X-ray crystal structure analyses, both crystallize in the triclinic space group P 1. The [As4O2Cl10]2– ion can be regarded as a centrosymmetric association product of two Cl2AsOAsCl2 molecules and two Cl– ions, each Cl– ion being coordinated with all four As atoms. In the [As2OCl6]2– ion the As atoms are linked via the O atom and two Cl atoms.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号