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1.
An integrated Xray diffraction study was performed on polycrystals and single crystals of three new isostructural phases with general formula Ag4A2[M(NO2)4]3 (M = Pd, Pt; A = K, Rb). Data on the crystal structure solution (CAD4 diffractometer, MoK radiation, graphite monochromator = 2–30° are presented. In one crystallographically independent [M(NO2)4]2- complex anion, the planar square coordination of the central atom is completed to 4 + 2 by two oxygen atoms at a distance of 3.02–3.12 in the other anion, it is completed to 4 + 1 + 1 by an oxygen atom at a distance of 3.12–3.30 and an Ag+ cation at a distance of 3.04–3.11 . Part of the Ag+ cations form Ag - Ag dimers with a distance of 3.03–3.07. Crystalchemical analysis of known structures containing [Pd(NO2)4]2- complex anions was performed. It has been established that in none of the cases do any of the possible limiting configurations occur.  相似文献   

2.
Procedures for synthesis of the first nitrochloride complex of nitrosoruthenium(II), fac-K2[RuNO(NO2)2Cl3], are described and the mechanism of its formation is suggested. The compound was investigated by IR spectroscopy and X-ray phase and X-ray diffraction analyses. Crystal data for Cl3N3O5K2Ru: a = 7.050(1), b = 7.524(2), c = 10.125(2) , = 90.44(3), = 103.17(3), = 90.51(3)°, V = 522.9 3, space group , Z = 2, d calc = 2.589 g/cm3. The structure consists of the complex anions fac-[RuNO(NO2)2Cl3]2– and K+ cations. The complex crystallizes as triclinic plates and red orange prisms; it is well soluble in water, not readily soluble in KCl solutions, and insoluble in ethanol and acetone; the complex is stable when stored in air.  相似文献   

3.
Palladium clusters Pd4(SEt)4(OAc)4(I) and Pd6(SEt)12(II) were synthesized and studied. Their structure was determined by X-ray diffraction analysis. For I, a= 9.774(2) Å, b= 10.821(2) Å, c= 13.061(3) Å, = 92.88(3)°, V= 1379.6(5) Å3, (calcd.) = 2.182 g/cm3, space group P21/n, Z= 4, N ref= 1558, and R= 0.031; for II, a= 10.581(1) Å, b= 10.584(2) Å, c= 11.478(2) Å, = 101.62(1)°, = 104.95(1)°, = 106.74(1)°, V= 1135.2(4) Å3, (calcd) = 2.007 g/cm3, space group P1, Z= 1, N ref= 2828, and R= 0.022. In cluster I, four Pd atoms form a planar cycle. The neighboring palladium atoms are bound by two acetate or by two mercaptide bridges, the Pd···Pd distances being 3.036–3.195 Å. In cluster II, Pd atoms form a planar six-membered cycle with Pd···Pd distances of 3.083–3.127 Å. The neighboring palladium atoms are bound by two mercaptide bridges. The formation of analogous clusters in solution was confirmed by IR spectroscopy.  相似文献   

4.
Conventional thermoanalytical curves provide little information on the thermal decomposition of Ca(NO3)2 · CO(NH2)2 · 3 H2O. In contrast from quasi-isothermal-quasi-isobaric thermogravimetric curves the mechanism can easily be interpreted. After the complex melts at 60°C, the solution formed is weight constant up to 135°C in the labyrinth crucible. The solution begins to boil at 135°C and gradually loses water, its boiling point increasing. The solution becomes saturated at 200°C. Thereafter, Ca(NO3)2 · CO(NH2)2 separates out while the boiling point does not change. After the departure of the water, the CO(NH2)2 immediately decomposes and Ca(NO3)2 remains.In an open crucible the above transformation is complicated by decomposition of typeAB (s)=A (s)+B (g) solution evaporation drying of solid residue, surface crust formation, etc. In conventional thermoanalysis the latter processes accompany the above processes (melting-solution formation-loss of water during boiling) which hampers interpretation of the conventional curve.
Zusammenfassung Herkömmliche thermoanalytische Kurven liefern wenig Informationen über die thermische Zersetzung von Ca(NO3)2 · CO(NH2)2 · 3 H2O. Quasi-isotherme/quasi-isobare thermogravimetrische Kurven dagegen ermöglichen leicht eine Interpretation des Mechanismus. Nach dem Schmelzen des Komplexes bei 60°C bleibt das Gewicht der Lösung im Labyrinthtiegel bis 135°C konstant. Die Lösung beginnt bei 135°C zu sieden und verliert zunehmend an Wasser, wobei der Siedepunkt ansteigt. Die Lösung erreicht den Sättigungspunkt bei 200°C. Danach scheidet sich Ca(NO3)2 · CO(NH2)2 ohne weitere Veränderung des Siedepunktes ab. Nach Entfernung des Wassers zersetzt sich das CO(NH2)2 sofort und Ca(NO3)2 bleibt zurück.In einem offenen Tiegel wird die obige Umwandlung durch Zersetzung des TypesAB (s)= =A (s)+B(g), durch Verdampfung der Lösung, durch Trocknung des festen Rückstandes, durch Oberflächenverkrustung usw. kompliziert. Diese Prozesse begleiten bei der herkömmlichen Thermoanalyse die oben erwähnten Vorgänge (Schmelzen-Lösungsbildung-Wasserverlust durch Sieden), wodurch die Interpretation der herkömmlichen Kurven erschwert wird.

(N3)2·(N2)2·3 2O . , - , . 60° 135°. 135° . - 200°. , (N3)2 · (N2)2 . , . , ABpac.=Apac + Bpac., , , .. : — — , .


The authors are indebted to Prof. E. Bulewicz and Prof. E. Pungor for valuable discussions.They thank Mrs. M. Kiss and Miss I. Fábián for technical assistance.  相似文献   

5.
The crystal and molecular structure of (BzlMe3N) 2 + [Fe2OCl6]2- has been determined. The asymmetric unit contains two benzyltrimethylammonium cations and two half -oxo-bis(trichloro-iron(III)) anions. The bridging -oxygen atoms of these anions are located over crystallographic symmetry elements. Therefore, the two anions resulting from the symmetry operations correspond to two different conformers presenting angular and linear dispositions of the Fe-O-Fe bond angle. Mössbauer spectrum consists of two asymmetric lines that are adequately simulated by two equally populated quadrupole doublets associated with the two iron sites.  相似文献   

6.
Synthesis of the complex [Rh(NO2)3(NH3)3] is described. The compound crystallizes as monoclinic colorless plates. Crystal data: a = 7.176(10), b = 10.407(2), c = 10.989(2) , = 93.27°, V = 819.3(2) 3, space group , Z = 4, d calc = 2.367 g/cm3. The structure is molecular and built of neutral complexes having cis-facial configuration. The unit cell of the crystal contains two independent complexes.  相似文献   

7.
Photobromination of SiH4 under uv-irradiation at various wavelengths has been studied. Rate constants for the elementary reactions Br(2P3/2)+SiH4HBr+SiH3 (k=3.2×10–11 exp(–21.8±2.5)/RT, cm3/s) and Br* (2P1/2)+SiH4HBr+SiH3 (k*=(3±1)×10–13 cm3/s) have been determined in the temperature range from 300 to 415 K.
- . Br(2P3/2)+SiH4HBr+SiH3, k=3,2×10–11 exp (–21,8±2,5)/RT 3/ Br*(2P1/2)+SiH4HBr+SiH3, k*=(3±1)×10–13 3/ 300–415 K.
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8.
Kinetic parameters for the decomposition of 8-pentadecanone ketohydroperoxides in the oxidized ketone medium and the effect of caprylic acid on the rate and mechanism of hydroperoxide decomposition have been studied. The decomposition of hydroperoxide into molecular products follows mainly the ionic mechanism.
8- . . , .
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9.
This paper describes a new method for the synthesis of the -iminoketonate complex Pt(ktf)2 using 1,1,1-trifluoro-4-iminopentan-2-one as a bidentate ligand. An X-ray study has been performed on the polycrystals and single crystals of the compound. The single crystal X-ray diffraction analysis was carried out on a CAD-4 diffractometer (MoK radiation, /2 scan mode). Crystal data: a = 10.217(2), b = 10.231(2), c = 10.924(2) , = 83.12(3), = 63.38(3), = 70.77(3)°, V = 963.4(3) 3, space group P1, Z = 2, d calc = 1.721 g/cm3. The Pt atom has a distorted planar square environment; the average lengths of Pt–N and Pt–O coordination bonds coincide (1.97 ). The mean value of the chelate angle is 94.2°. The environment of Pt is completed to bipyramid by the hydrogen atoms of the neighboring molecules. The structure of the compound is molecular. The differently oriented molecules of the complex are linked into chains down the x axis with Pt...Pt distances of 5.10 . A comparative crystal-chemical analysis of the structures of Pt(ktf)2 and Pd(ktf)2 and their O,O-chelate analogs — Pt(II) and Pd(II) trifluoroacetylacetonates — has been carried out. An X-ray study of Pt(tfa)2 and Pd(tfa)2 has been accomplished, and crystal data are given.  相似文献   

10.
Summary Dichloro complexes of PdII, [Pd(L–L)Cl2], where L–L=1-(thiomethyl)-2-(diphenylarsino)ethane (S–As) or 1-(thiomethyl)-2-(diphenylphosphino)ethane (S–P) andtrans-[PdL2Cl2], where L=diphenyl(2-phenylethyl)-phosphine (PE), diphenyl(1-naphthyl)phosphine (PN) orN-methyl-2-thiophenealdimine (SN), have been prepared and characterized. The reactions of these complexes with MeLi were investigated. The dimethyl complexes [Pd(L–L)Me2] (L–L=S–As, S–P) and [Pd(PE)Me2] were isolated and characterized. Reaction of [Pd(L–L)Me2] (L–L=S–As, S–P) with HCl affords the monomethyl derivatives [Pd(L–L)Me(Cl)]. In contrast to the Pt analogues, [Pd(L–L)Me2] and [Pd(L–L)Me(Cl)] are relatively less stable than [Pt(L–L)Me2] and [Pt(L–L)Me(Cl)].  相似文献   

11.
A new molybdenum(VI) complex, Li2[Mo2O6(C2O4)] · 2 H2O (LMO), was prepared and characterized by chemical analysis and IR spectral studies. Its thermal decomposition was studied by using TG and DTA techniques. LMO loses its two moles of water between 75 and 170° to give the anhydrous product, which decomposes in three stages between 240 and 380°. The first two stages occur in the temperature ranges 240–280° and 280–305°, to give intermediates with the tentative compositions Li6[Mo6O19(C2O4)2] and Li6[Mo6O20(C2O4)], respectively. In the third stage, which extends up to 380°, Li6[Mo6O20(C2O4)] decomposes to give the end-product, Li2Mo2O7.
Zusammenfassung Ein neuer Molybdän(VI)-Komplex der Formel Li2[Mo2O6(C2O4)] · 2 H2O (LMO) wurde dargestellt und durch chemische Analyse und IR-spektroskopisch charakterisiert. Die thermische Zersetzung dieses Komplexes wurde mittels TG und DTA untersucht. LMO verliert die zwei Wassermoleküle zwischen 75 und 170° unter Bildung des wasserfreien Produktes, das zwischen 240 und 380° in drei Stufen zersetzt wird. Die in den Temperaturbereich von 240–280° und 280–305° verlaufenden ersten zwei Reaktionsschritte ergeben Intermediäre der tentativen Zusammensetzung Li6[Mo6O19(C2O4)2] bzw. Li6[Mo6O20(C2O4)]. In dem sich bis 380° erstreckenden dritten Reaktionsschritt wird Li6[Mo6O20(C2O4)] unter Bildung des Endproduktes Li2Mo2O7 zersetzt.

Li2[MO2O6(C2O4] · 2 2 . . - 70–170° , , 240–380°. 240–280° 280–305° - Li6[Mo6O19(C2O4)2] Li6[Mo6O20(C2O4)]. - 380° Li2Mo2O7.


The authors are grateful to Prof. S. N. Tandon, Head of the Chemistry Department, for providing the research facilities.  相似文献   

12.
Summary 2-Mercaptoquinoline is introduced as a sensitive and selective reagent for copper and palladium. Spot test detections and spectrophotometric determinations of these metals have been carried out. 0.03 g Cu at a limiting concentration of 1 430,000 can be detected by the spot technique on a filter paper, and 0.025 g Cu at a limiting concentration of 1 106 by means of the spot plate method. Palladium was determined by measuring the optical density of the orange-yellow colour at 450 m developed in alcoholic medium at pH 1.4–2.8. The sensitivity is 0.009 g Pd per cm2 (Sandell).The author feels deeply indebted to Professor P. Rây, Director and Professor (Hony) of Inorganic Chemistry, for his helpful suggestions, and to Dr. P. C. Banerjee for his kind interest in the work.  相似文献   

13.
The reduction of NO by carbon monoxide on SnO2 has been studied in the temperature range from 90 to 450°C. The complicated temperature dependence of the reaction rate is due to the interaction of CO an CO2 with the catalyst.
NO SnO2 90–450°C. , CO CO2 .
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14.
The dehydrogenation and hydrogenolysis of n-butane (n-C4) over a Ru–Al2O3 catalyst (0.849 w/w% Ru) have been studied at 490°C at different time factors. Some runs have also been made on pure -Al2O3 at 490°C and on Ru-black at temperatures between 100 and 490°C, feeding n-butane and hydrogen. The analysis of the selectivity vs. time factor allows to prove that the initial reactions taking place are n-C4 dehydrogenation to 1-butene and 2-butenes and skeletal isomerization to isobutane. The initial molar selectivity to the n-butenes reaches about 70%. A qualitative reaction scheme is proposed.
- (-C4) Ru–Al2O3 (0,849 .% Ru) 490°C . -Al2O3 490°C Ru- 100–490°C - . , -C4 1- 2- . - 80%. .
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15.
The reactions of half-sandwich diselenolate Mo and W complexes Cp#M(NO)(SePh)2 (M = Mo; Cp# = Cp (1a), MeCp (1b); M = W; Cp# = Cp (1c)) with (Norb)Mo(CO)4, Ni(COD)2 and Fe(CO)5 have been investigated. Treatment of (1a), (1b) and (1c) with (Norb)Mo(CO)4 in PhMe gave the bimetallic complexes: CpMo(NO)(-SePh)2Mo(CO)4 (2a), MeCpMo(NO)(-SePh)2Mo(CO)4 (2b) and CpW(NO)(-SePh)2Mo(CO)4 (2c) in moderate yields. Irradiation of (1a) and (1c) in the presence of Fe(CO)5 gave heterobimetallic complexes CpMo(CO)(-SePh)2Fe(CO)3 (3a) and CpW(NO)(-SePh)2Fe(CO)3 (3c). Ni(COD)2 reacts with two equivalents of (1a), (1b) and (1c) to give [CpMo(NO)(-SePh)2]2Ni (4a), [MeCpMo(NO)(-SePh)2]2Ni (4b) and [CpW(NO)(-SePh)2]2Ni (4c) in good yields. The new heterobimetallic complexes were characterized by i.r., 1H-n.m.r., 13C-n.m.r. and EI-MS spectroscopy.  相似文献   

16.
The structure of bis(ethylenediamine)nickel(II)tetracyanopalladate(II), Ni(NH2CH2CH2NH2)2Pd(CN)4, has been determined from three-dimensional X-ray data, using Weissenberg photographs. The compound crystallizes with two molecules in the monoclinic space group P21/n with a=7.174(10), b=10.740(15), c=10.135(15) Å, =115.0(5)°. The measured and the calculated density is 1.83 g/cm3. Anisotropic refinement gave a finalR factor of 10.2%. The structure consists of infinite chains, -Pd-C-N-Ni-N-C-, parallel to thec-axis. Two trans-nitrogen atoms of the square Pd(CN) 4 2– are linked to Ni, leading thus to a polynuclear compound with an octahedral [NiN6] group in agreement with visible and infrared spectra. The trans-Ni(NH2CH2CH2NH2)2(NC)2-group has an asymmetric gauche ()-conformation. Average distances are: Pd-C: 1.96 Å, CN: 1.15 Å, Ni-N: 2.08 Å.
Zusammenfassung Die Struktur von Bis(äthylendiamin)nickel(II)-tetracyanopalladat(II), Ni(NH2CH2CH2NH2)2Pd(CN)4, wurde mit Hilfe von Weissenbergaufnahmen ermittelt. Die Substanz kristallisiert mit zwei Formeleinheiten in der monoklinen Raumgruppe P21/n mit den Zelldimensionen a=7,174(10), b=10,740(15), c=10,135(15) Å, =115,0(5)°. Die gemessene und die berechnete Dichte betragen beide 1,83 g/cm3. Die, Verfeinerung unter Berücksichtigung anisotroper Temperaturfaktoren führte zu einem. R-Wert von 10,2%. Unendlich lange-Pd-C-N-Ni-N-C-Ketten sind parallel derc-Achse angeordnet. In Übereinstimmung mit den Spektren im sichtbaren und infraroten Bereich handelt es sich um einen polynuklearen Komplex, indem die trans-Cyanidgruppen von Pd(CN) 4 2– als ambidente Liganden zu einer oktaedrischen [NiN6]-Koordinationseinheit führen. Die trans-Ni(NH2CH2CH2NH2)2(NC)2-Gruppe weist eine asymmetrische gauche ()- Konformation auf. Mittlere Atomabstände betragen: Pd-C=1,96 Å. CN=1,15 Å, Ni-N=2,08 Å.

Résumé La structure du tétracyanopalladate (II) de bis (éthylènediamine) nickel (II) a été déterminée à partir de données tri-dimensionnelles aux rayons X, avec des photographies de Weissenberg. Le composé cristallise avec deux molécules dans le groupe spatial monoclinique P21/n avec les param ètres a=7.174 (10), b=10.740 (15), c=10.135 (15) Å, =115.0 (5)°. La densité mesurée et calculée est 1,83 g/cm3. L'amélioration anisotrope donne un facteurR final de 10,2%. La structure se présente comme des chaînes infinies -Pd-C-N-Ni-N-C, parallèles à l'axec. Deux atomes d'azote trans du groupe carré Pd(CN) 4 2– sont liés à Ni, conduisant ainsi à un composé polycyclique avec un groupe [NiN6] octaédrique, ce qui est en accord avec le spectre visible et infra-rouge. Le groupe trans-Ni (NH2CH2CH2NH2)2(NC)2 a une conformation assymétrique gauche (). Les distances moyennes sont Pd-C: 1,96 Å, CN:1,15 Å, Ni-N: 2,08 Å.


Dedicated to the memory of Professor Hans-Ludwig Schläfer.  相似文献   

17.
The thermal treatment of the pentafluorophenyl derivativesM(C6F5)2Dxn [M=Pd (n=2, 3) or Pt (n=2); Dx=dioxane] leads to the formation of the new dioxane adducts M(C6F5)2Dx (M=Pd, Pt) and Pt(C6F5)2Dx1.5. Calculations of the order of reaction and the activation energy of some of the decomposition reactions are described. The values were determined by the Coats-Redfern and Freeman-Carroll methods. Structural data on the isolated intermediates were obtained by infrared spectroscopy and magnetic susceptibility measurements.
Zusammenfassung Die thermische Behandlung der PentafluorphenylderivateM(C6F5)2Dxn [M=Pd (n=2, 3) oder Pt (n=2); Dx=Dioxan] führt zu der Bildung der neuen DioxanaddukteM(C6F5)2Dx (M=Pd, Pt) und Pt(C6F5)2Dx1.5. Die Berechnungen der Reaktionsordnung und der Aktivierungsenergie einiger Zersetzungsreaktionen werden beschrieben. Die Werte wurden durch die Methoden von Coats-Redfern und Freeman-Carroll bestimmt. Die Strukturangaben der isolierten Zwischenprodukte wurden durch Infrarotspektroskopie und Messung der magnetischen Suszeptibilität erhalten.

(6F5)2, M=Pd n=2, 3 Pt n=2, - , -M(C6F5)2 (=Pd, Pt) (6F5)21,5. , — —. .
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18.
Zusammenfassung Die Kristalldaten der- und der-Modifikation des KH(JO3)2 wurden bestimmt; die von früheren Autoren angegebene rhombische-Modifikation konnte nicht aufgefunden werden. Bei der thermischen Zersetzung ergeben beide Kristallarten zunächst Wasser, dann I2O5 und O2; es bleibt KI zurück. Als Zwischenstufe entsteht K2I4O11. Die Temperaturen der DTA- und DTG-Spitzen zeigen bei der- und der-Modifikation sicher nachweisbare Unterschiede.
The crystal data of the- and-modifications of KH(IO3)2 were determined. The rhombic-modification which has been described by earlier authors could not be obtained. In the course of thermal decomposition both crystal types release water, then I2O5 and O2, leaving a residue of KI. As an intermediate, K2I4O11 is formed. The temperatures of the DTA and DTG peaks of the- and-modifications, were found to be different.

Résumé On a déterminé les données cristallographiques des modifications et de KH(IO3)2. On n'a pas pu retrouver la modification mentionnée par d'autres auteurs dans des travaux plus anciens. Lors de la décomposition thermique, les deux modifications cristallographiques perdent d'abord de l'eau, puis I2O5 et O2; le résidu est constitué par KI. On décèle K2I4O11 comme intermédiaire. Les températures des pics ATD et TGD des deux modifications montrent des différences marquées.

- (IO3)2.- , . , I25 2, KI. 2I411. - , , .
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19.
The behavior of some supported Ni catalysts for methane synthesis from CO and steam in correlation with the specific metal-support interactions is discussed.
CO . .
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20.
TheSomogyi-Nelson colorimetric method is applied in a new manner more suitable for evaluating the kinetics of the enzyme hydrolysis of sodium carboxymethylcellulose (Na-CMC) catalyzed by the cellulase complex. By means of selective inhibition of a chosen enzyme from the cellulase complex it became possible to trace the effect of the other enzymes included in its composition.
Kinetik und Mechanismus der Hydrolyse von Natriumcarboxymethylcellulose (Na-CMC) durch einen Cellulase-Komplex
Zusammenfassung Die kolorimetrische Methode nachSomogyi undNelson wird nach einem neuen Verfahren zur Verfolgung der Kinetik der hydrolytischen Spaltung von Natriumcarboxymethylcellulose (Na-CMC), katalysiert durch den Cellulase-Komplex, angewandt. Durch selektive Inhibierung eines bestimmten Enzyms des Cellulase-Komplexes kann man die Wirkung der anderen zu seiner gesamten Zusammensetzung gehörenden Enzyme verfolgen.

Symbols Used E enzyme (E—cellulase;E—exo-cellobiohydrolase;E—-glucosidase) - [E] w weight concentration of enzymeE - S substrate (Na-CMC—sodium carboxymethylcellulose) - [S]0 weight concentration of substrateS - I inhibitor (I—lactose;I—calcium chloride;I—condurrite-B-epoxide) - P product (P—oligosaccharides;P—cellobiose;P—D-glucose) - P end product (K , K , K ) - DP degree of polymerization - DS degree of substitution - ES enzyme-substrate complex (E S, E S, E S) - EP enzyme-product complex (E P, E P) - EI enzyme-inhibitor complex (E I, E I, E I) - M s molecular mass of substrateS - K s substrate constant (K s , K s , K s ) - K I inhibitor constant (K I , K I , K I ) - K m Michaelis-Menten constant - k +1,k +2 (k +2 ,k +2 ,k +2 ) forward rate constants - k –1 reverse rate constant - 0 initial rate of reaction - V maximal reaction rate - A change in absorbance - molar absorption coefficient - wavelength Herrn Prof. Dr.Hans Tuppy zum 60. Geburtstag herzlichst gewidmet.  相似文献   

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