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1.
The preparation, identification and some properties of three new clathrate compounds Cd(mea)[Pd(CN)4] · 2C6H6, Cd(mea)2[Pd(CN)4] · C4H4S and Cd(mea)2[Pd(CN)4] · C4H4NH (mea = HO-CH2-CH2-NH2) are described.
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2.
Zusammenfassung Antimon(III)- und Antimon(V)-Verbindungen lassen sich nach Überführung in Na3[SbS4] durch Fällung mit [Cr en3]Cl3·3 1/2H2O als [Cr en3] [SbS4]·2 H2O quantitativ bestimmen. Es wird eine Arbeitsvorschrift angegeben, die es gestattet, in 5 bis 10 ccm Lösung 1 bis 2 mg Sb mit hinreichender Genauigkeit zu bestimmen.
Summary After being converted to Na3[SbS4], antimony(III) and antimony(V) compounds can be determined quantitatively by means of [Cr en3]Cl3·3 1/2 H2O which gives a precipitate of the formula [Cr en3][SbS4]·2 H2O. Directions are given for a technique which allows to determine in 5–10 cc. of solution, 1–2 mg. Sb with sufficient accuracy.

Résumé On peut doser quantitativement des combinaisons d'antimoine(III) et d'antimoine(V), après les avoir transformé par précipitation avec [Cr en3]Cl3· 3 1/2 H2O en [Cr en3][SbS4]·2 H2O. L'auteur indique une méthode d'analyse, permettant de doser avec une exactitude suffisante 1–2 mg de Sb dans 5–10 ccm de solution.
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3.
We present a comprehensive study of the structural properties and the thermal expansion behavior of 17 different Prussian Blue Analogs (PBAs) with compositions MII3[(M′)III(CN)6]2·nH2O and MII2[FeII(CN)6nH2O, where MII=Mn, Fe, Co, Ni, Cu and Zn, (M′)III=Co, Fe and n is the number of water molecules, which range from 5 to 18 for these compounds. The PBAs were synthesized via standard chemical precipitation methods, and temperature-dependent X-ray diffraction studies were performed in the temperature range between −150 °C (123 K) and room-temperature. The vast majority of the studied PBAs were found to crystallize in cubic structures of space groups Fm3?m, F4?3m and Pm3?m. The temperature dependence of the lattice parameters was taken to compute an average coefficient of linear thermal expansion in the studied temperature range. Of the 17 compounds, 9 display negative values for the average coefficient of linear thermal expansion, which can be as large as 39.7×10−6 K−1 for Co3[Co(CN)6]2·12H2O. All of the MII3[CoIII(CN)6]2·nH2O compounds show negative thermal expansion behavior, which correlates with the Irving–Williams series for metal complex stability. The thermal expansion behavior for the PBAs of the MII3[FeIII(CN)6]2·nH2O family are found to switch between positive (for M=Mn, Co, Ni) and negative (M=Cu, Zn) behavior, depending on the choice of the metal cation (M). On the other hand, all of the MII2[FeII(CN)6nH2O compounds show positive thermal expansion behavior.  相似文献   

4.
Summary Solid complexes of 3-acetyl-1,5-diaryl and 3-cyano-1,5-diaryl formazans were prepared and characterized by elemental analysis, IR, NMR, TGA and DTA analyses. Based on these studies, the suggested general formula for the complexes is [M(HL) m (OH) n or (NO 3 or Cl) x ·(H2O) y or (C2H5OH orDMSO) z , where HL=formazanM=Ce3+, Th4+, and UO 2 2+ ,m=1–2,n=0–3,x=0–3,y=0–4 andz=0–3. The metal ions are expected to have coordination numbers 6–8.
Strukturuntersuchungen an 3-Acetyl-1,5-diaryl- und 3-Cyan-1,5-diaryl-formazan-Chelaten mit Cer(III), Thorium(IV) und Uran(VI)
Zusammenfassung Die hergestellten Chelate wurden mittels Elementaranalyse, IR, NMR, TGA und DTA charakterisiert. Darauf basierend wird die generelle Formel [M(HL) m (OH) n bzw. (NO 3 oder Cl) x ·(H2O) y oder (C2H5OH bzw.DMSO) z ] vorgeschlagen, wobei HL=Formazan,M=Ce3+, Th4+ oder UO 2 2+ ,m=1–2,n=0–3,x=0–3,y=0–4 undz=0–3. Die Metallionen haben Koordinationszahlen von 6–8.
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5.
Liu  Jie  Mei  Wen-Jie  Xu  An-Wu  Tan  Cai-Ping  Ji  Liang-Nian 《Transition Metal Chemistry》2003,28(5):500-505
A series of novel heteropoly blues, Ln2H2[SiMo11Ni(H2O)O39] · nH2O (Ln = La, Ce, Pr, Nd, Sm, or Gd), had been prepared and characterized by elemental analysis, i.r., u.v., c.v., t.g.–d.t.a., XPS, 29Si-n.m.r., electrochemistry and magnetic susceptibility. Compared with non-reduced heteropolyoxometallates, the heteropoly blue anion in Ln2H2[SiMo11Ni(H2O)O39] · nH2O still retains the -Keggin structure but with a slight distortion, with Ni and Mo atoms distributed statistically in the crystal. The antiviral activities of these complexes have been studied using tomato mosaic virus. Ln2H2[SiMo11Ni(H2O)O39] · nH2O show excellent antivirus activities, and the cure rate reaches to 80–90%.  相似文献   

6.
A number of polynuclear mixed carboxylates of nickel(II) with the general composition [Ni(OOCCH3)2–n (OOCR) n ] x (whereR=C13H27, C15H31, C17H35 and C21H43 andn=1 or 2) have been synthesized by the transacylation reactions of anhydrous nickel acetate with higher carboxylic acids in refluxing toluene. On recrystallization from benzene-alcohol mixtures, mono-alcoholate complexes, Ni(OOCCH3)2–n (OOCR) n ·ROH (whereR=CH3 and C2H5) have been isolated. All these derivatives have been characterized by the molecular weight determinations, infra-red and electronic reflectance spectra and magnetic susceptibility measurements.
Synthese und Eigenschaften einiger gemischter Carboxylat-Komplexe von Nickel(II)
Zusammenfassung Komplexe des Typs [Ni(OOCCH3)2–n (OOCR) n ] x (mitR=C13H27, C15H31, C17H35 und C21H43,n=1 oder 2) wurden aus wasserfreiem Nickelacetat mit höheren Carbonsäuren in siedendem Toluol erhalten. Bei der Kristallisation aus Benzol-Alkohol-Mischungen wurden Monoalkoholate Ni(OOCCH3)2–n (OOCR) n ·ROH (mitR=CH3 und C2H5) isoliert. Die Charakterisierung der Komplexe erfolgte mittels Molekulargewichtsbestimmung, Infrarot- und Elektronenspektren und der Messung der magnetischen Susceptibilität.
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7.
Kou  Hui-Zhong  Gao  Dong-Zhao  Bu  Wie-Ming  Fan  Yu-Guo  Liao  Dai-Zheng  Cheng  Peng  Jiang  Zong-Hui  Yan  Shi-Ping  Wang  Geng-Lin  Li  Tian-Jian  Tang  Jin-Kui 《Transition Metal Chemistry》2001,26(4-5):457-460
Two CrIII–FeIII complexes, K2[Cr(salen)(H2O)][Fe(CN)6]·H2O (1) and [trans-Cr(tn)2Cl2]3[Fe(CN)6]·6H2O (2), have been prepared. Crystal structure determination shows that complex (2) possesses an ionic salt structure. General physical measurements and magnetic studies indicate that (1) assumes a cyanide-bridged dinuclear structure, and that the CrIII–FeIII magnetic coupling through the cyanide bridge is antiferromagnetic, which can be rationalized by the overlap of magnetic orbitals of the same symmetry.  相似文献   

8.
The reaction of alkali metal hexacyanoferrate(II/III) with (CH2)6N4 (hexamethylenetetramine, abbreviated HMT) in an acidic medium yielded crystalline compounds of stoichiometries HK2[Fe111(CN)6]·2HMT·4H2O, H2K2[Fe11(CN)6]·2HMT·4H2O, and HNa2[Fe111(CN)6]· 2HMT·5H2O. Their crystal structures are based on a packing of three molecular components: neutral and/orprotonated HMT, hexacyanoferrate, and an alkali metal ion-water cluster. The resulting three-dimensional supramolecular framework is constructed from the coordination of the alkali metal ion by aqua ligands as well as [Fe(CN)6]{n–} and HMT units, and further stabilization is achieved by hydrogen bonding between water molecules and the noncoordinated nitrogen atoms of HMT and hexacyanoferrate.  相似文献   

9.
Zusammenfassung Es wurden die elektrochemischen Eigenschaften des Redox-Systems K4[Fe(CN)6]-K3[Fe(CN)6] in Ameisensäure-Wasser-, Essigsäure-Wasser-, Propionsäure-Wasser- und n-Buttersäure-Wasser-Gemischen untersucht. Die Veränderungen des Redoxpotentials, der Leitfähigkeit und der Dielektrizitäts-konstante wurden studiert.Es wurde bewiesen, daß die Potentialveränderung des Redox-Systems bei kleiner Säurekonzentration (n s<0,6–0,7) vor allem durch die Wasserstoffionen-Konzentration der Lösung bestimmt wird. Mit der Zunahme der H+-Konzentration nimmt die Aktivität des [Fe(CN)6]4– in größerem Maße ab als die des [Fe(CN)6]3–.Bei großer Säurekonzentration beeinflußt dagegen hauptsächlich die Anionsolvatation durch das Lösungsmittelgemisch die Verschiebung des Redoxpotentials. Die Solvatation ruft eine Strukturveränderung hervor, wodurch die Elektronen-population der Lösungsmittelmoleküle in der Nähe der Cyanoferrat-Ionen abnimmt, die Elektronen-Acceptor-Wirkung des Lösungsmittels wächst. Dieser Prozeß bewirkt in bekannter Weise die Zunahme des Redoxpotentials.
The electrochemical behaviour of redox systems in mixed solvents, II.: TheK 4[Fe(CN) 6]-K 3[Fe(CN) 6] system in fatty acid-water mixtures
The electrochemical behaviour of the K4[Fe(CN)6]-K3[Fe(CN)6] system has been investigated in mixtures of water with formic, acetic, propionic and n-butyric acid, resp. The change of the redox potential, the conductivity and the dielectric constant has been studied. It has been proved that the change of the redox potential of the system at low acid concentration (n s<0.6–0.7) is determined by the H+ concentration. Increasing the H+ concentration, the activity of the [Fe(CN)6]4– decreases in a higher extent than the activity of [Fe(CN)6]3–.On the other hand, at high acid concentration the shift in the redox potential is influenced first of all by the anion solvating effect of the solvent. The solvation causes such a change in the structure, that the electron population of the solvent molecules around the [Fe(CN)6]4– ions decreases, the acceptor strength of the solvent increases. It is well known that this process causes an increase in the redox potential.


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10.
Summary The crystal structure of (PPh4)2[ReO(OH)(CN)4]·5H2O has been determined from three-dimensional x-ray diffraction data. The light brown crystals are monoclinic, space group P21/n, with cell dimensionsa=16.753(2),b=19.928(2),c=15.338(2) Å and =101,894(1)°,z=4, Dm=1.45(1) g cm–3. The anisotropic refinement of the 6088 observed reflections converged to R=0.077.The [ReO(OH)(CN)4]2– ion has a distorted octahedral geometry. Bond distances: Re =1.70(1), Re–OH=1.90(1) and ReCav=2.12(2) Å. The Re atom is displaced by 0.08 Å out of the plane formed by the four carbon atoms towards the terminal oxo ligand.  相似文献   

11.
The properties of a series of lanthanide hexacyanoferrate(II) n-hydrates were studied by thermal analysis, IR spectroscopy and X-ray diffraction. Thermal analysis results show that there are three kinds of complexes in this series, KLn[Fe(CN)6]·4 H2O (Ln=La-Nd), KSm[Fe(CN)6]·3H2O and KLn[Fe (CN)6]·3.5H2O (Ln=Eu-Lu). On the basis of IR spectra, only two different types of complexes show obvious differences. Indeed for the tetrahydrates, there is one OH stretching band; on the other hand, for the samarium phase and the 3.5 hydrates a splitting of HOH stretching mode is observed. The splitting of the H2O band is correlated to a symmetry modification. The crystal structures of the three complexes KLn[Fe(CN)6]·3.5H2O (Ln=Eu, Er and Lu) were determined; they belong to orthorhombic symmetry (space group Cmcm). Heat-treated powders have been investigated by X-ray analysis which show the formation of thin needles of LnFeO3 at 600°C.  相似文献   

12.
The crystal structure of [Zn(en)2- (NC)2Ni(CN)2 Zn(en)][Ni(CN)4]· 3 H2O consists of infinite positively charged wave-shaped layers of composition [Zn(en)2-(NC)2Ni(CN)2- Zn(en)] n 2n+ with the [Ni(CN)4]2– anions and water molecules included between them. Both Ni atoms exhibit square-planar coordination. The chelate bonded en (=ethylenediamine) and N-bonded cyano ligands around two independent zinc atoms form a deformed tetrahedron and a deformed octahedron, respectively. Yellow needles of the complex belong to the orthorhombic space groupPbcm witha = 6.977(1),b = 25.407(4),c = 14.876(2)Å,Z = 4,D m = 1.74(1) g cm–3 andD c = 1.739 g cm–3. The structure was refined toR = 6.31 %.  相似文献   

13.
The synthesis, spectral properties and crystal structures of Cs2[W(bpy)(CN)6]·2H2O and (AsPh4)2[W(bpy)(CN)6]·3.5H2O are described. The anions of both salts show distorted antiprismatic geometry with very similar bond lengths and angles. The structure of the [W(bpy)(CN)6]2– anion is independent of the type of cation, in contrast to the octacyanotungstate(IV).  相似文献   

14.
Zusammenfassung Die chemischen Effekte des isomeren Überganges von80mBr wurden bei Temperaturen von–78° C und–196° C an mit80mBr markierten Proben von [Co(NH3)5 X]Br3.2 nH2O und [Co(en)2 X 2']Br3.1 nH2O untersucht (X=NH3, NCS, NO2, OH2, ONO, ONO2, F, Cl, Br, I, undX'=en, NH3, NCS, Cl, Br). Es zeigte sich, daß die Ligandenausbeute an80Br, in den Komplexen mit abnehmender Frequenz des Maximums in der ersten Absorptionsbande des [Co(NH3)5 X] und des [Co(en)2 X 2'] zunimmt. Mit anderen Worten, weniger stabile, Liganden werden leichter von Radiobrom ersetzt als Folge des isomeren Überganges in festen Komplexen.
Chemical effects of the isomeric transition of80mBr in pentammincobalt(III) and bisethylenediaminecobalt(III) bromides
The chemical effects of the isomeric transition of80mBr were investigated at temperatures of–78° C and–196° C with80mBr-labeled samples of [Co(NH3)5 X]Br3.2 nH2O and [Co(en)2 X 2']Br3.1 nH2O (X=NH3, NCS, NO2, OH2, ONO, ONO2, F, Cl, Br, I, andX'=en, NH3, NCS, Cl, Br). The ligand yield of80Br in the complexes was found to increase with the decrease in the frequency of the maximum in the first absorption band of [Co(NH3)5 X] and [Co(en)2 X 2']. In other words, less stable ligands were more easily replaced by radiobromine as a consequence of isomeric transition in solid complexes.


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Herrn Prof. Dr.E. Broda zum 60. Geburtstag gewidmet.  相似文献   

15.
Zusammenfassung Für die Bestimmung von Vanadinspuren eignet sich die Bromat-Ascorbinsäure-Reaktion vom Landolt-Typ, für die das Gesehwindigkeitsgesetz in folgender Form Gültigkeit hat: –d[BrO3 ]/d=[BrO3 K 1([(6H8O6+K v[v]+K 2 [Br][H+]2). Die Verfasser bestimmten auf Grund der Daten für die Reaktionszeit der Landolt-Reaktion den Wert vonK 1 und die Aktivierungsenergie der Bromat-Ascorbinsäure-Reaktion.K 1=2,5·10/Mol–1 · min–1 (25° C) bzw. 15,408 Kcal/Mol.
Catalytic reactions in trace analysis and investigation of their mechanisms. VII
Summary The bromate-ascorbic acid reaction of the Landolt type is suited to the determination of traces of vanadium. The velocity law is valid in the following form: –d[BrO3 ]/d=[BrO3 K 1([(6H8O6+K v [v]+K 2[Br][H +]2). Using the data for the reaction time of the Landolt-reaction, the authors determined the value ofK 1 and the activation energy of the bromate-ascorbic acid reaction.K 1=2.5 · 10–2/mol–1 · min–1 (25° C) or 15.408 kcal/mol.
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16.
Strain measurement and quasiequilibrium thermogravimetry were used to study the dissociation processes of two clathrates, [Ni(MePy)4(NCS)2]·(MePy) and [Cu(MePy)4(NCS)2]·2/3(MePy), accompanied by the liberation of MePy into the gaseous phase. In the Ni clathrate dissociation process in the temperature range 298–368 K the liberated MePy was redistributed between the solid clathrate and gaseous phases; the MePy vapour pressure over the clathrate is a function of temperature and the guest contenty, which agrees with the presence in the MePy-[Ni(MePy)4(NCS)2] system of a wide range of -clathrate solutions, [Ni(MePy)4(NCS)2y(MePy). The same methods used to study the Cu clathrate dissociation resulted in conclusions different from those obtained for the dissociation process of the above clathrate: the process is described by the equation [Cu(MePy)4(NCS)2]·2/3(MePy)solid =[Cu(MePy)2(NCS)2]solid+22/3(MePy)gas; the temperature dependence of the Mepy vapour pressure over the solid sample does not depend on its composition, which points to the absence from the system of solid solutions based on the clathrate. Standard changes of the enthalpy, entropy, and isobaric-isothermal reaction potential for the temperature range 292–325 K are equal to 178.6±1.7 kJ (mole of clathrate)–1, 463±5.6 J (mole of clathrate)–1 K–1, and 40.4±2.4 kJ (mole of clathrate)–1, respectively.  相似文献   

17.
Summary New complex salts of lanthanide thiocyanates with hexamethylenetetramine of the general formulaLn(NCS)3·2[N4(CH2)6·nH2O, whereLn=La,Pr,Nd,Sm,Gd,Dy,Er andn=0–10, have been analyzed. IR spectra have been obtained in the range of 200–4000 cm–1, frequencies of vibrations of low and high hydration state compounds have been analyzed, and differences between the structures of the coordination speheres of these salts are demonstrated. Diffractometric examinations and measurements of the magnetic susceptibility of several salts have been performed.
Synthese und spektroskopische, diffraktometrische und magnetische Untersuchungen von Verbindungen der Lanthaniden mit Rhodanid und Hexamethylentetramin
Zusammenfassung Neue Komplexsalze der Lanthaniden mit Rhodanid und Hexamethylentetramin mit der allgemeinen FormelLn(NCS)3·2[N4(CH2)6nH2O (Ln=La,Pr,Nd,Sm,Gd,Dy,Er;n=0–10) wurden untersucht. Die IR-Spektren der Verbindungen im Bereich von 200–4000 cm–1 wurden aufgenommen. Die Schwingungsfrequenzen hoch- und niederhydrierter Verbindungen wurden analysiert und die Unterschiede in der Struktur der Koordinationssphäre bestimmt. An einigen Komplexen wurden diffraktometrische Untersuchungen und Messungen der magnetischen Suzaptibilität durchgeführt.
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18.
Summary The cluster compound H4[Ta6Cl12(CN)6] · 12H2O was prepared and identified by potentiometric titrations, i.r. and visible spectra and by three-dimensional single-crystal x-ray diffraction methods. Discrete [Ta6Cl12(CN)6]4– ions contain a linear Ta–CN unit with Ta–C=2.21(4) and C–N=1.16(5) Å, respectively. Each nitrogen atom is hydrogen bonded [2.63(12)Å] to two oxygen atoms.  相似文献   

19.
Zusammenfassung Die Wechselstrompolarographie ist für die Messung der Geschwindigkeitskonstanten der Elektrodenprozesse im Bereich von 5·10–3–5·10–2 cm sec–1 anwendbar. Das bestätigen auch die Ergebnisse, die für ein Modellsystem erhalten wurden. Experimentell wurde die Anwendbarkeit der Methode am Redoxsystem [CrCl2(H2O)4]+–[CrCl2(H2O)4] in sauren 4–9n-LiCl-Lösungen nachgeprüft, und zwar durch den Vergleich der Resultate mit den Ergebnissen der Messungen derFaraday-impedanz und der Methode der überlagerten Spannung.
Application of alternating current polarography for the measurement of rate constants
The method of alternating current polarography is known to be applicable to the measurement of rate constants of electrode reactions within the range of 5·10–3 to 5·10–2 cm sec–1. This follows also from the results obtained with model systems. The applicability of the method has been studied in the redox-system [CrCl2(H2O)4]+–[CrCl2(H2O)4] in acid solutions of 4N to 9N LiCl. The results were compared with those obtained by measuring the faradaic impedance and with the results of the method of periodically changed rectangular voltage.


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20.
The crystal structures of four novel Hofmann-diam-type clathrates [Cd(tn)Ni(CN)4]·1.72(o-MeC6H4NH2),3-o, [Cd(tn)Ni(CN)4]·0.5(m-ClC6H4NH2),3-m, [Cd(daptn)Ni(CN)4]·1.5(p-MeC6H4NH2),5-p and [Cd(dahpn)Ni(CN)4]·1.5(2-MeC9H6N),7-q have been determined by single crystal X-ray diffraction method [tn:n=3, daptn:n=5, dahpn:n=7 for NH2(CH2) n NH2.3-o crystallizes in the monoclinic space groupP2/m,a=7.538(2),b=9.314(5),c=7.670(2) Å, =91.03(2)°,Z=1,R=0.047 for 1252 reflections;3-m: orthorhombicPbam,a=12.1714(7),b=15.798(1),c=7.737(1) Å,Z=4,R=0.044 for 1871;5-p: monoclinicP21/a,a=13.736(3),b=22.014(4),c=7.762(3) Å, =91.04(3)°,Z=4,R=0.047 for 5281; and7-q: orthorhombicPbam,a=13.599(2),b=27.938(4),c=7.619(2) Å,Z=4,R=0.054 for 3098. Their host structures are topologically the same to those of the previously reported Hofmann-diam-type clathrates: the two-dimensional [CdNi(CN)4] networks are spanned by NH2(CH2) n NH2 at every Cd atom to build up the three-dimensional hosts. The number of cavities available for the guest is regulated by the deformation of the 2D networks and the diamine ligand in the host structure. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82192 (37 pages).  相似文献   

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