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1.
Benzophenone analog 3 has been synthesized and characterized by the X-ray diffraction (XRD) method. The compound crystallizes in a monoclinic space group P21/c with cell parameters a = 7.701(8) Å, b = 7.151(5) Å, c= 28.323(3) Å, = 104.639(4)°, Z = 4. The structure exhibits intra- and intermolecular hydrogen bonding of the type N–HO, C–HO, and N–HN. The molecules are interlinked through hydrogen bonds forming an infinite chain. This polymeric-like structure may play an important role in biological activity.  相似文献   

2.
The reactions of TMA4Ge4S10 (TMA=tetramethylammonium), Cu(NO3)23H2Oand 4,4-bipy under hydrothermal environment result in the formation of (H2bipy)2Ge4S10(bipy)7H2O (1), which has been structurally characterized by single crystal X-ray analysis. The 3-D structure of 1 can be viewed as an inorganic-organic hybrid supramolecular hydrogen-bonding (hydrogen bonds: O–HO, N–HN, C–HO, N–HO, and O–HS) and - stacking network containing Ge4S4– 10 clusters and novel [H2bipybipyH2bipy] trimers.  相似文献   

3.
The tetranuclear Au(I) pyrazolate complex, [(dppm)2Au4(3,5-Ph2Pz)2](NO3)2  H2O, 1, has been synthesized and structurally characterized. It is the first tetranuclear pyrazolate of Au(I) to have been found, although the trinuclear pyrazolates of Au(I) are well known. Complex 1 exhibits luminescence at 77 K when excited at 333 nm with an emission maximum at 454 nm. The emission has been assigned to ligand to metal charge transfer, LMCT, based upon the vibronic structure that is observed. The complex crystallizes in the monoclinic space group P21/c, with a=19.33(3) Å, b=20.26(3) Å, c=19.80(3) Å, =106.74(2)°, V=7425(17) Å3, Z=8, and R=0.058. The Au    Au distances are Au(1)    Au(4)=3.185(3) Å, Au(1)    Au(2)=3.230(3) Å, Au(2)    Au(3)=3.079(3) Å, and Au(3)    Au(4)=3.280(3) Å.  相似文献   

4.
Compounds of the compositions [2(18-crown-6)6(H2O)2(C2H4Cl2){Pt2+(C2H4)}(Pt2Cl10)2–], [4(18-crown-6)2(OH3)+2(OH2)2(NH3)(Pt2Cl10)2–], [(dibenzo-18-crown-6)6(H2O){Pt2+(C2H4)}(Pt2Cl10)2–], and [4(dibenzo-18-crown-6)2(OH3)+2(OH2)2(NH3)Pt2Cl10)2–] were prepared by reactions of H2PtCl6 with 18-crown-6 and dibenzo-18-crown-6.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 10, 2004, pp. 1593–1599.Original Russian Text Copyright © 2004 by Guseva, Busygina, Khasanshin, Polovnyak, Yarkova, Yusupov.This revised version was published online in April 2005 with a corrected cover date.  相似文献   

5.
The crystals of [Co6H2O][Co4H2O2Gly]2SO4 were studied by X-ray diffraction analysis (triclinic, P , a = 5.975(5), b = 15.469(5), c = 6.765(5) , =120.71(5), =83.23(5), =98.77(5)°). The structure contains complex cations of two types: [Co6H2O]2+ and [Co4H2O2Gly]2+ and SO 4 2– anions linked by hydrogen bonds and electrostatic forces. Three chemically nonequivalent charged layers can be distinguished in the structure: one layer is formed by cobalt hexaaqua complexes, another by [Co4H2O2Gly]2– complexes, and the third layer consists of sulfate anions interlaying the former two. The layers alternate along the b axis and are connected by a 3D system of hydrogen bonds.  相似文献   

6.
Redox reactions of disulfiram (DSF) were studied in aqueous solutions using the pulse-radiolysis technique. Reactions of DSF with one-electron oxidants Br2 - and N3, generated pulse radiolytically in aqueous solution at pH 7, yielded a transient (max = 480 nm) which exhibited the characteristics of a disulphide cation radical and decayed by second-order kinetics. Reactions of DSF with halogenated peroxyl radicals CCl3O2, CHCl2O2, CH2ClO2 and CBr3O2 led to the formation of an adduct absorbing at 580 nm. The reduction potential was estimated to be 1.24 ± 0.06 V vs. NHE.  相似文献   

7.
Mercury(II) halides, HgX2 (X = Cl, Br, I) react with 1,3-benzothiazole-2-thione (btztH) in methanol solutions giving the HgX2(btztH) and HgX2(btztH)2 types of compounds. Mercury(II) acetate gives the thiolato compound Hg(btzt)2 because of the deprotonation of btztH. Hg(btzt)2 reacts with 2,2-bipyridine (bipy) giving a 1:1 complex. IR, 1H, and 13C NMR spectral studies indicate that btztH acts as a monodenatate ligand through the S thione donor atom in all complexes. The X-ray crystal structure determinations of [HgI2(btztH)]2, HgBr2(btztH)2, Hg(btzt)2, and Hg(btzt)2(bipy) have been carried out revealing tetrahedrally coordinated mercury atom in [HgI2(btztH)]2 and HgBr2(btztH)2, while in Hg(btzt)2(bipy) 2 + 2 coordination is achieved through strong Hg (N(bipy) contacts. A linear coordination in Hg(btzt)2 is not affected by the Hg N contacts, which are longer than in Hg(btzt)2(bipy), but still shorter than the van der Waals sum of mercury and nitrogen covalent radii. [HgI2(btztH)]2 exists as centrosymmetrical dimer with a Hg2I2 bridging core. The dimeric molecules are linked by the intermolecular hydrogen bonds between the terminal iodine atom and the NH group [3.63(1) Å] into infinite chains along the z-axis. There are N–H Br(bridging) intermolecular hydrogen bonds in HgBr2(btztH)2 joining molecules into endless chains along the x-axis. The Br(bridging) atom acts as double proton acceptor and two NH groups as proton donors [NH Br(bridging) 3.278(9) and 3.338(7) Å]. The mercury to sulfur and mercury to halogen bond distances in [HgI2(btztH)]2 and HgBr2(btztH)2 are discussed in relation to the analogous compounds, revealing strong influence of hydrogen bonds on their relative strengths as well as crystal packing requirements of the ligand. The sulfur and halogen atoms are more tightly bound to mercury implicating severe distortion of the coordination polyhedron in the structures in which they do not take part in hydrogen bonds formation. The influence of steric requirements of the ligands in Hg(btzt)2 and Hg(btzt)2(bipy) on the distortion of the mercury coordination polyhedra accompanied with the relative strength of Hg N contacts is considered.  相似文献   

8.
The hydration of the sulphatealuminate phase Ca4(Al6O12)(SO4) at room temperature was observed by means of differential calorimetry and quantitative X-ray diffraction phase analysis in situ. The results were used to evaluate the kinetics of the hydration process and to explain the causes of the exothermic effects: an initial surface reaction, the formation of a highly dispersed system, and the crystallization of monosulphate, Ca4(Al2O6)(SO4) · 12H2O, and gibbsite, Al(OH)3. The experiments showed an increase in efficiency of hydration with a higher mass ratio of water to solid phase (from 143.8 kJ/mol) atw/s=1 to 170.0 kJ/mol atw/s=10).
Zusammenfassung Die Hydration der Sulfat-aluminat-Phase Ca4(Al6O12)(SO4) bei Zimmertemperatur wurde mittels Differentialkalorimetrie und quantitativer in-situ-Röntgenbeugungs-Phasenanalyse verfolgt. Ein vergleich der Ergebnisse erlaubte die Kinetik des Hydratationsprozesses abzuschätzen und die Ursache der exothermen Effekte zu klären: Anfängliche Oberflächenreaktion, Bildung eines hochdispersen Systems, Kristallisation von Monosulfathydrat Ca4(Al2O6)SO4·12H2O und Hydrargillit Al(OH)3. Die Versuche zeigten eine Zunahme der Hydratationseffektivität mit steigendem Verhältnis Wasser: Feststoff (w/s) von 143,8 kJ mol–1 beiw/s=1 auf 170,0 kJ mol–1 beiw/s=10.

in situ 4(l6)(S4). , , 4(l26)(S4) · 122 l()3. : 143,8 –1 1 170,0 · –1 10.
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9.
Spin traps, which are diamagnetic centers (SiO)2Si, are used to register low-molecular radicals OH, NH2, and H formed by the reactions of H2O and NH3 molecules with the radicals (Si–O)3Si and (Si–O)3Si–O stabilized on the silica surface. The experimental data and the results of quantum-chemical calculations for model systems are used to determine the mechanism and thermochemical characteristics of these reactions. A new paramagnetic center (Si–O)2SiNH2 was identified on the silica surface, and its radiospectroscopic characteristics are determined.  相似文献   

10.
Indium complex of 13,17-dibutyl-2,3,7,8,12,18-hexamethyl-5-azaporphyrin (Cl)InMAP was synthesized, and acid-base interactions of the meso-nitrogen atoms in (Cl)InMAP and its diaza analog (Cl)InDAP with acetic and trifluoroacetic acids were studied by 1H NMR and electronic spectroscopy. Depending on the medium, the complexes and proton-donor species HA give rise to acid solvates >N(HA)n which are converted to final acid-base interaction products, H-complexes >NH+A(HA)m or ionic associates >NH+A(HA)l , as the acidity of the medium rises. In acetic acid solution, the acid solvates derived from more basic (Cl)InMAP exist in equilibrium with the H-associates (pK a1 = 4.45±0.03). From (Cl)InDAP, the corresponding H-associates are formed only in the presence of H2SO4 (pK a1 = 2.10±0.03). In more polar media (solutions of trifluoroacetic acid in methylene chloride), ionic associates are formed, which involve one [(Cl)InMAP, pK 1 = 2.46±0.02] or two meso-nitrogen atoms [(Cl)InDAP, pK 1 = 2.11±0.03, pK 2 = 0.41±0.04).Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 9, 2004, pp. 1546–1556.Original Russian Text Copyright © 2004 by Stuzhin, Ivanova, Migalova.This revised version was published online in April 2005 with a corrected cover date.  相似文献   

11.
The double malonates of gadolinium, terbium and holmium with sodium, of the type Na5Ln(C3H2O4)4.7.5H2O, have been studied by means of thermal analysis. A mechanism of thermal dehydration and decomposition has been proposed on the basis of the results obtained.
Zusammenfassung Doppelmalonate von Gadolinium, Terbium und Holmium mit Natrium des Typs Na5Ln(C3H2O4)4.7,5 H2O wurden mittels thermischer Analyse untersucht. Für die thermische Dehydratisierung und Zersetzung wird ein auf den erhaltenen Ergebnissen basierender Mechanismus vorgeschlagen.

, Na5Ln(C3H2O4)4.7.5H2O. .


Part II. Communicated  相似文献   

12.
Novel pyridoxal oxime derivatives were prepared and characterized by means of IR, 1H and 13C NMR spectroscopy. The crystal structures of the 3-hydroxy-4-hydroxyiminomethyl-5-hydroxymethyl-1,2-dimethylpyridinium iodide 1 and 3-hydroxy-4-hydroxyiminomethyl-5-hydroxymethyl-1,2-dimethylpyridinium chloride monohydrate 2 were determined by X-ray analysis. The both compounds crystallize in the triclinic crystal system, space group P . Crystal data: 1 a = 6.286(2) Å, b = 8.748(4) Å, c = 11.736(4) Å, = 104.02(3)°, = 94.70(3)°, = 107.44(6)°, V = 589.0(4) Å3, Z = 2, R = 0.0526; 2 a = 6.8980(5) Å, b = 8.6409(6) Å, c = 11.1777(6) Å, = 111.138(5)°, = 93.114(6)°, = 105.158(5)°, V = 591.57(7) Å3, Z = 2, R = 0.0492. The bond distances and angles in both structures agree very well. The main difference between these structures was observed in the orientation of the hydroxymethyl group with respect to the pyridinium ring. In the both structures intramolecular hydrogen bond forming six-membered ring were observed. The intermolecular OsI hydrogen bonds in the crystal structure of the compound 1 form dimers. In the crystal structure of compound 2, the water molecules and chlorines build eight-membered rings, which are also connected to pyridinium cations by OsCl and OsO intermolecular hydrogen bonds forming a three-dimensional network.  相似文献   

13.
Sodium iodide complexes of 13-membered azo-(I)and azoxycrown ethers (II) have been synthesized. Compound I[Na(L1 trans)2]IH2O is triclinic witha = 11.53(2), b = 15.74(2), c = 19.17(2) Å, = 98.93(9), = 105.51(9), = 89.20(9) deg.; Z = 4, space groupP1. Compound II [Na(L2)2]I is orthorhombic witha = 12.451(2), b = 13.796(3), c = 18.667(4)Å; Z = 4, space group P212121. In bothcomplexes the cation is coordinated tochain oxygen atoms and to one nitrogen atom of the azoor azoxy unit. The ability of bothligands to form complexes in relation to thegeometry of the azo or azoxy subunit of themacrocycle is discussed.  相似文献   

14.
The methods of optical, ESR, and IR spectroscopy were used to obtain data on the structure and mechanism for the formation of the products in the reaction of dioxasilirane groups (Si–O)2Si 2 (DOSG) stabilized on the silica surface. Depending on the regime of the reaction (temperature and methane pressure), the process is accompanied by the formation of various products: methoxy (–O–CH3) and ethoxy (–O–C2H5) groups. The process mechanism is elucidated: this is a free-radical reaction in which paramagnetic sites are generated in the reaction between DOSG and methane molecules. The formation of final products is due to the reactions >Si(O)(OCH3) + CH4 >Si(OH)(OCH3) + CH3 and >Si(O–CH2)(OH) + CH3 >Si(OH)(OC2H5). The ratio of the rate constants of methyl radical addition to (Si–O)2Si: and (Si–O)2Si 2 at room temperature was determined experimentally (4.6 ± 1.0).  相似文献   

15.
HREELS studies of NO molecular adsorption on clean and hydrogen covered Pt(111) have revealed that a reversible transition between bridge (1) and on-top (2) states of NOads is realized in the (NO+H2)/Pt(111) system. In the presence of Hads the adsorption of NO in the 1 state is inhibited and the main state of NOads is 2. Upon heating the layer (2-NOads+Hads) hydrogen desorption is accompanied by on-top to bridge state conversion.
NO Pt(III). , (NO+H2)/Pt(III) (1) (2) NO. H NO 1 , , 2 NO. (2-NO+H) NO .
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16.
Nitrate radical (NO3) reactions with benzene (R-1), toluene (R-2), p-xylene (R-3), p-cresol (R-4) and mesitylene (R-5) have been studied by laser photolysis/long path laser absorption (LP-LPLA) in aqueous solution. Rate constants of k1=(4.0±0.6) 108, k2=(1.2±0.3)109, k3=(1.6±0.1)109, k4= (8.4±2.3)108 and k5=(1.3±0.3)109 lmol-1s-1 were obtained at T=298 K. In addition, reaction rate coefficients for SO-5+Fe2+prod. (R-6) and SO-5+Mn2+prod. (R-7) of k6=(4.3±2.4) 107 lmol-1s-1 and k7=(4.6±1.0)106 lmol-1s-1 (T=298 K, I0) have been obtained by the application of laser photolysis/UV-VIS broadband diode array spectroscopy. A new laser photolysis/UV-long path laser absorption experiment has been applied to study the reaction of the Cl-2 radical anion with dissolved sulfur(IV). For the reactions Cl-2+HSO-32Cl-+H++SO-3 (R-8) and Cl-2+SO2-32Cl-+SO-3 (R-9) rate coefficients of k8=(1.7±0.2)108 lmol-1s-1 (T=298 K, I0) and of k9=(6.2±0.3)107 lmol-1s-1 (T=279 K, I0) were obtained.  相似文献   

17.
Zusammenfassung Die thermische Zersetzung von Lithiumhexacyanoferrat (III) in Luft führt in drei Temperaturbereichen, d.h. zwischen 250 und 400°, 500 und 650° und 925 und 1000° zur Bildung ferromagnetischer Produkte. Durch Röntgendiffraktionsuntersuchung und magnetische Messungen wurde bewiesen, daß im ersten Temperaturbereich-Fe2O3 die für die ferromagnetischen Eigenschaften der Zersetzungsprodukte verantwortliche Phase ist, während in den anderen Bereichen diese Eigenschaften durch Lithiumferrit der Formel Li0.5Fe2.5O4 verursacht werden.
The thermal decomposition of lithium hexacyanoferrate (III) in air leads to the formation of ferromagnetic products in three temperature ranges, namely 250–400°, 500–650° and 925–1000°. By X-ray diffraction studies and magnetic measurements it has been proved that in the first temperature region-Fe2O3 is the phase responsible for the ferromagnetic properties of the decomposition products, whereas in the other regions these properties are due to the presence of the lithium ferrite Li0.5Fe2.5O4.

Résumé La décomposition thermique du ferricyanure de lithium dans l'air conduit à des produits ferromagnétiques dans trois intervalles de température: 250–400°, 500–650° et 925–1000°. Par diffraction des rayons X et mesures magnétiques, on montre que lors de la première étape de décomposition c'est l'oxyde-Fe2O3 qui est responsable des propriétés ferromagnétiques des produits de décomposition, tandis que pour les deux autres étapes, le ferromagnétisme est dû à la présence de ferrite de lithium de formule Li0.5Fe2.5O4.

-()- : 250–400°, 500–650° 925–1000°. - , , , , -Fe2O3. Li0.5Fe2.5O4.
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18.
Simultaneous TG/DTG/DTA studies under non-isothermal conditions have been carried out in air and nitrogen on some halo-dithiocarbamates of the general formula XM[S2CN(CH2)5]2 (X=Cl, Br and I; andM=As, Sb and Bi).E* values for the 1st stage of decomposition were determined by graphical methods and the TTN temperatures were calculated from the TG profiles. A possible mechanism of the decomposition reaction is suggested, based on the thermoanalytical and pyrolysis results and the mass spectral data. The kinetic analysis data on five of the above dithiocarbamates and nine complexes of the general formula M[S2CN<]3 (M=As, Sb and Bi; and N<=NEt2, N(CH2)5 and N(CH2)4O) were studied by the QIA (quasi-isothermal analysis) technique in air atmosphere. An example of kinetic parameter (k andn) estimation for the first decomposition stage is given for Bi[S2CN(CH2)5]3, with the assumption of different kinetic equations.
Zusammenfassung Einige helo-Dithiocarbamate der allgemeinen Formal XM[S2CN(CH2)5]2 (X=Cl, Br und I;M=As, Sb und Bi) wurden mittels simultaner TG/DTG/DTA unter nichtisothermen Bedingungen in Luft und Stickstoff untersucht. Für den ersten Zersetzungsschritt wurden E*-Werte durch graphische Methoden bestimmt und die TIN-Temperaturen aus den TG-Profilen berechnet. Ein auf den Ergebnissen der Thermogravimetrie und Pyrolyse sowie auf massenspektroskopischen Daten beruhender möglicher Mechanismus wird vorgeschlagen. Fünf der angeführten Dithiocarbamate und 9 Komplexe der allgemeinen Formel M[S2CN<]3] (M=As, Sb und Bi;N=NEt2, N(CH2)5 und N(CH2)4O) wurden mittels QIA (quasi-isotherme Analyse) in Luft untersucht. Als Beispiel ist die Bestimmung der kinetischen Parameter (k undn) für den ersten Schritt der Zersetzung von Bi[S2CN(CH2)5]3 unter Annahme verschiedener kinetischer Gleichungen angegeben.

, - XM[S2CN(CH2)5]2, =Cl, r l, a M=As, Sb Bi. a , -. - . M[S2CN<]3, M=As, Sb Bi, a N<=NEt2, N(CH2)5 N(CH2)4O. k 3[S2N(2)5]3.
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19.
In aqueous solution, PM12–nVnO40 –(3+n) (M=Mo,W) hetero-polyanions provide a much faster oxidation of NO than mononuclear VO 2 + ions, yielding HNO2, NO 3 and reduced HPA.
, PM12–nVnO40 –(3+n) (M=Mo,W) , VO 2 + , NO HNO2 NO 3 .
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20.
The kinetics of thermal dehydration of [Ni2Al(OH)6]2SO4.nH2O has been studied through the analysis of isothermal weight loss data. The results obtained seem to indicate that the process is governed by a diffusion mechanism up to an value which is dependent on the temperature. An explanation is provided for this behaviour on the basis of the structural properties of the compound and the nature of the water loss.
Zusammenfassung Die Kinetik der thermischen Dehydratisierung von [Ni2Al(OH)6]2SO4.nH2O wurde mittels isothermer TG untersucht. Die Ergebnisse scheinen darauf hinzudeuten, daß der Prozeß bis zu einem von der Temperatur abhängigen -Wert von einem Diffusionsmechanismus bestimmt wird. Für dieses Verhalten wird basierend auf den strukturellen Eigenschaften der Verbindung und der Natur der Wasserabgabe eine Erklärung gegeben.

, [Ni2Al(OH)6]2SO4.nH2O. , , . , .
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