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1.
DSC measurements were carried out for [Ni(H2O)6](ClO4)2 (sampleH) and [Ni(D2O)6](ClO4)2 (sampleD) in the temperature range 300–380 K. For both compounds two anomalies on the DSC curves were detected. The results for sampleH are compared to those previously obtained using adiabatic calorimetry method. For both compounds studied in this work the high-temperature transition appears at the same temperature while the low-temperature one is shifted towards higher temperatures in sampleD. Disorder connected with H2O or D2O groups is suggested in the intermediate phase between the low- and high-temperature transitions.  相似文献   

2.
Reaction of the N-(2-pyridyl)carbonylaniline ligand (L) with Cu(NO3)2, Cu(ClO4)2, Zn(ClO4)2, Ni(NO3)2 and PdCl2 gives complexes with stoichiometry [Cu(L)2(H2O)2](NO3)2, [Cu(L)2(H2O)2](ClO4)2, [Zn(L)2(H2O)2] (ClO4)2, [Ni(L)2(H2O)Cl](NO3) and PdLCl2. The new complexes were characterized by elemental analyses and infrared spectra. The crystal structures of [Cu(L)2(H2O)2](NO3)2, [Cu(L)2(H2O)2](ClO4)2, and [Zn(L)2(H2O)2](ClO4)2 were determined by X-ray crystallography. The cation complexes [M(L)2(H2O)2] contain copper(II) and zinc(II) with distorted octahedral geometry with two N-(2-pyridyl)carbonylaniline (L) ligands occupying the equatorial sites. The hexa-coordinated metal atoms are bonded to two pyridinic nitrogens, two carbonyl oxygens and two water molecules occupying the axial sites. Both the coordinated water molecules and uncoordinated amide NH groups of the N-(2-pyridyl)carbonylaniline (L) ligands are involved in hydrogen bonding, resulting in infinite hydrogen-bonded chains running in one and two-dimensions.  相似文献   

3.
The family of compounds [M(dapdoH2)2](ClO4)2 (dapdoH2 = diacetylpyridine dioxime; M = Mn, Co, Fe, Ni, Cu and Zn) were prepared and their properties studied and compared with the literature. The X-ray crystal structures of [Mn(dapdoH2)2](ClO4)2, (1), and [Cu(dapdoH2)2](ClO4)2, (5), are reported. Both exhibit the expected coordination sphere with six nitrogen atoms coordinated to the central metal, but each shows deformation from pseudo-octahedral geometry. In the case of (1), this takes the form of a significant tilting of one ligand, while in (5) the ligands are twisted toward each other, reducing the dihedral angle between them to 72°. In both cases, hydrogen bonding between the perchlorate ions and the oxime O–H groups links the units into chains. Attempts to prepare and crystallize the corresponding anions led to isolation of the oxidized products.  相似文献   

4.
《Polyhedron》1987,6(5):897-905
Homo- and heterodinuclear complexes of composition [M2L2](ClO4)2·4H2O, [CuML2](ClO4)2·nH2O (M = Ni, Co or Mn; L = L1 or L2) and [CuML2Cl2]·2H2O (M = Ni or Co) have been synthesized with the dinucleating ligands 2-hydroxy-5-methyl- benzene-1,3-dicarbaldehyde (HL1) and 1,3-diacetyl-2-hydroxy-5-methylbenzene (HL2). These compounds have been characterized and their chemical reactivities investigated. The electrochemical behaviour of [M2L22](ClO4)2·4H2O and [CuML22](ClO4)2·nH2O complexes have been examined in acetonitrile and dimethyl sulfoxide using Hg and Pt electrodes. The cyclic voltammograms obtained with a Hg electrode show quasi-reversible electron transfers for both metal centres that often get complicated due to decomplexation of metal ions and adsorption phenomena. On a Pt electrode irreversible electron transfers occur at more negative potentials.  相似文献   

5.
The reaction of Cu(ClO4)2·6H2O and Cd(ClO4)2 with di-(2-picolyl)sulfur (dps) leads to the formation of mononuclear complexes [Cu(dps)(H2O)(ClO4)](ClO4) (1) and [Cd(dps)2](ClO4)2 (2). The crystal structure of 1 exhibits a distorted square pyramidal geometry, coordinated by one sulfur and two nitrogen atoms from the dps ligand, one water molecule and one perchlorate oxygen atom. For 2, the environment around cadmium atom is in a distorted octahedron with four nitrogen and two sulfur atoms from the dps ligand. Cyclic voltammetric data show that complexes undergo two waves of a one-electron transfer corresponding to M(II)/M(III) and M(II)/M(I) processes. Spectral and electrochemical behaviors of the complexes are also discussed.  相似文献   

6.
Polysulfonylamines. LXXXIV. Isotypic Structures in the Dimesylamide Complex Series [M(H2O)4{(CH3SO2)2N}2] (M?Mg, Ca, Ni, Cu, Zn, Cd) and [M(py)4{(CH3SO2)2N}2] (M?Ni, Cu, Zn, Cd) The crystal structures of the trans-octahedral complexes [M(H2O)4{(CH3SO2)2N}2] (M?Ca, Cd), in which the dimesylamide anion acts as a monodentate O-ligand and a tetrafunctional hydrogen bond acceptor, were determined by low-temperature X-ray diffraction. Both belong to an isotypic series (triclinic, space group P1 , Z = 1) that had previously been characterized for M?Mg, Ni, Cu and Zn (Z. Anorg. Allg. Chem. 1996 , 622, 1065). In this structure there exists an extended network of strong hydrogen bonds which is probably the underlying reason why the structure type surprisingly persists across the whole series. To support this explanation by indirect evidence from comparison with suitable structures devoid of strong hydrogen bonding, the analogous trans-octahedral complexes [M(py)4{(CH3SO2)2N}2] (M?Mn, Co, Ni, Cu, Zn, Cd) were prepared by treating M[(CH3SO2)2N]2 with pyridine, and the crystal structures of the Ni, Cu, Zn and Cd compounds were studied by low-temperature X-ray crystallography. As anticipated, the four pyridine complexes do not form an isotypic series but instead two isotypic pairs consisting of the Ni and Zn compounds (monoclinic, space group P21/n, Z =2) and of the Cu and Cd complexes (triclinic, space group P1, Z = 1). All molecules of the aqua and the pyridine complexes display crystallographic centrosymmetry. In the hydrates, the mean M? OH2 and the M? O(anion) distances are 232.6 and 232.7 pm for M ? Ca, 225.5 and 230.3 pm für M ? Cd. The mean M? N and the M? O(anion) bond lengths of the pyridine species amount to 211.8 and 213.1 pm for M ? Ni, 217.0 and 218.5 pm for M ? Zn, 232.8 and 234.4 pm for M ? Cd; the corresponding values for the severely Jahn-Teller distorted Cu complex are 203.6 and 254.5 pm. In the crystals of the pyridine complexes, each methyl group is connected through a weak C? H…?O bond to a sulfonyl oxygen atom of an adjacent molecule.  相似文献   

7.
水热条件下,合成了三个新的配合物[Ni(en)3] (ndt) ·H2O 1, [Co(en)3] (ndt) ·H2O 2 和[Mn(en)3] (ndt) ·H2O 3。晶体结构通过X-射线单晶衍射进行了表征。三个配合物均属于单斜晶系,Cc空间群。[M(en)3]2+阳离子、ndt阴离子和结晶水分子通过氢键自组装出相同结构的三维网。通过紫外-可见-近红外漫反射光谱对这三个配合物的光吸收性能和能带进行了测定。  相似文献   

8.
IR spectra of Mn(en)M(CN)4·2C6H6 (M=Cd or Hg), and IR and Raman spectra of Cd(en)M(CN)4·2C6H6 (M=Cd or Hg) clathrates are reported. The spectral features suggest that the first two compounds are similar in structure to the later two Td-type clathrates.  相似文献   

9.
Synthesis and Crystal Structure of Hydrogen Selenates of Divalent Metals – M(HSeO4)2 (M = Mg, Mn, Zn) and M(HSeO4)2 · H2O (M = Mn, Cd) New hydrogen selenates M(HSeO4)2 (M = Mg, Mn, Zn) and M(HSeO4)2 · H2O (M = Mn, Cd) have been synthesized using MSeO4 (M = Mg, Mn, Zn, Cd) and 90% selenic acid as starting materials. The crystal structures have been determined by X-ray single crystal crystallography. The compounds M(HSeO4)2 (M = Mg, Zn) belong to the structure type of Mg(HSO4)2, whereas Mn(HSeO4)2 forms a new structure type. Both hydrogen selenate monohydrates are isotypic to Mg(HSO4)2 · H2O. In all compounds the metal atoms are octahedrally coordinated by oxygen atoms of different HSeO4-tetrahedra. In the HSeO4-tetrahedra the Se–OH-distances (mean value 1.70 Å) are about 0.1 Å longer than Se–O-distances (mean value 1.62 Å). In the structure of M(HSeO4)2 (M = Mg, Zn) there are zigzag chains of hydrogen bonded HSeO4-tetrahedra. The structure of Mn(HSeO4)2 is characterized by chains of HSeO4-tetrahedra in form of screws. Hydrogen bonds from and to water molecules connect double layers of MO6-octahedra and HSeO4-tetrahedra in the structures of M(HSeO4)2 · H2O.  相似文献   

10.
Polysulfonyl Amines. LXXIII. Metal(II) Dimesylamide Tetrahydrates: The Dimesylamide Anion as a Monodentate O-Ligand and a Tetrafunctional Hydrogen Bond Acceptor in the Isotypic Complexes [M(H2O)4{(CH3SO2)2N}2], where M = Magnesium, Nickel, Copper, or Zinc By treating aqueous HN(SO2CH3)2 solutions with the appropriate metal hydroxides, oxides, or carbonates, the crystalline tetrahydrates M[(CH3SO2)2N]2 · 4 H2O (M = Mg, Ca, Mn, Co, Ni, Cu, Zn, Cd) were obtained and analytically characterized. The crystal structures of the Mg, Ni, Cu and Zn compounds, as determined by single-crystal X-ray diffraction at low temperatures, reveal an isotypic series (triclinic, space group P1 , Z = 1). The structures consist of centrosymmetric trans-octahedral [M(H2O)4{(CH3SO2)2N}2] molecules in which the anionic ligand acts as a monodentate O-donor. For the Mg, Ni and Zn complexes, the M? OH2 and M? O(anion) distances lie in the ranges 203–206 pm and 209–214 pm, respectively. The copper compound features a marked Jahn-Teller distortion with Cu? OH2 = 195.8 and 197.7 pm and Cu? O(anion) = 232.5 pm. The cis-angles O? M? O of the four molecules do not deviate appreciably from 90°. The complex units are associated through a highly organized three-dimensional hydrogen bond network in which all the water protons act as donors and the non-coordinating oxygen atoms and the nitrogen atom of the anionic ligand are involved as acceptors. The H-bond pattern is subjected to a graph-theoretical analysis at the first and second levels.  相似文献   

11.
A series of homo‐, heterodinuclear and homotrinuclear copper(II) complexes containing a new Schiff base ligand and 1,10‐phenanthroline were synthesized. Based on results of elemental analyses, FTIR, 1H‐ and 13C‐NMR spectra, conductivity measurements and magnetic susceptibility measurements, the complexes had general compositions {[Cu(L)(H2O)M(phen)2](ClO4)2 [M = Cu(II), Mn(II), Co(II)]} and {[Cu3(L)2(H2O)2](ClO4)2}. The metal:L:phen ratio is 2:1:2 for the dinuclear copper(II) complexes and the metal:L ratio was 3:2 for the trinuclear copper(II) complex. The liquid–liquid extraction of various transition metal cations [Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Pb(II), Cd(II), Hg(II)] from the aqueous phase to the organic phase was carried out using the diimine–dioxime ligand. It was concluded that the ligand can effectively be used in solvent extraction of copper(II) from the aqueous phase to the organic phase. Furthermore, catalytic activitiy of the complexes for the disproportionation of hydrogen peroxide was also investigated in the presence of imidazole. Dinuclear copper(II)–manganese(II) complex has some similarity to manganese catalase in structure and activity. The interaction between these complexes and DNA has also been investigated by agarose gel electrophoresis; we found that the homo‐ and heterodinuclear copper complexes can cleave supercoiled pBR322 DNA to nicked and linear forms in the presence of H2O2. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

12.
IR spectra of Mn(adenine)2M(CN)4.C6H6 (M=Cd or Hg), andIR and Raman spectra of Cd(adenine)2M(CN)4.C6H6(M=Cd or Hg) are reported. The spectral data suggest thatthe host frameworks of these compounds are similarto those of the Hofmann-Td-type and the adeninecoordination is via N(10).  相似文献   

13.
IR spectra of Mn(NH3)2M(CN)4·2C6H6 (M=Cd or Hg), and IR and Raman spectra of Cd(NH3)2M(CN)4·2C6H6 (M=Cd or Hg) are reported. The spectral data suggest that the former two compounds are similar in structure to the latter two Td-type clathrates.  相似文献   

14.
The tetrafluoroborate of hexadimethylsulfoxidenickel(II) was synthesized and studied by differential scanning calorimetry. Seven solid phases of [Ni(DMSO)6](BF4)2 were revealed. Specifically, six phase transitions of the first order were detected between the following solid phases: stable KIb → stable KIa at T C6 = 335 K, metastable KIIb → metastable KIIa at T C5 = 368 K, metastable KIII → overcooled phase KI at T C4 = 378 K, metastable KIIa → overcooled phase KI at T C3 = 396 K, stable KIa → stable KI at T C2 = 415 K and stable KI → stable K0 at T C1 = 433 K. [Ni(DMSO)6](BF4)2 begins decomposition at 440 K with loss of one DMSO molecule per formula unit forming [Ni(DMSO)5](BF4)2 (phase L0) which melts next in two steps in the temperature range 550–593 K. From the entropy changes connected both with melting and with phase transitions, it can be concluded that phases KI, overcooled KI and K0 are orientationally dynamically disordered (ODIC) crystals. Stable phases KIb, KIa and metastable phase KIII are ordered solid phases. Metastable phase KIIa and metastable phase KIIb are more or less ordered solid phases.  相似文献   

15.
The methods of TG, DTA and DSC were used to study the thermal decompositions of [Ni(H2O)6](NO3)2 and [Ni(D2O)6](NO3)2 in an atmospheric air medium. Intermediates were isolated at 145, 230 and 245°, and were identified by quantitative analysis and IR spectroscopy. The following phase transitions were observed under the conditions of the experiment: melting of the salts, partial dehydration to the tetrahydrate, formation of basic nickel nitrate hydrate stable within a narrow temperature interval, and formation of NiO.
Zusammenfassung Mittels TG, DTA und DSC wurde die thermische Zersetzung von [Ni(H2O)6](NO3)2 und [Ni(D2O)6](NO3)2 in Luft untersucht. Bei Temperaturen von T=145°C, 230°C un 245°C konnten Intermediäre festgestellt werden, welche mittels quantitativer Analyse und IR-Spektroskopie identifiziert wurden. Unter den gegebenen experimentellen Bedingungen wurden folgende Phasenumwandlungen beobachtet: Schmelzen der Salze, partielle Dehydratation zu Tetrahydrat, Bildung von basishem Nickelnitrat-hydrat (stabil innerhalb eines schmalen Temperaturintervalles), schließliche Bildung von NiO.Aus den DSC-Daten wurden die Enthalpien der Phasenumwaldungen berechnet. DTA- und DSC-Daten zeigen, daß die Phasenunwandlungen bei [Ni(H2O)6](NO3)2 bei etwas niedrigeren Temperaturen liegen als bei [Ni(D2O)6](NO3)2.
  相似文献   

16.
Reactions between nickel(II) and copper(II) salts [M(L) n ](ClO4)2 [L: 2-(pyrazole-1-ylmethyl)pyridine; n = 3 for Ni(II) and n = 2 for Ni(II) and Cu(II)] and LiTCNQ or mixture of LiTCNQ/TCNQ and Et3NH(TCNQ)2 yielded [Ni(L)3](TCNQ)2 · H2O, [Ni(L)2(TCNQ)2], [Ni(L)3](TCNQ)3, [Ni(L)2(TCNQ)3], and [Cu(L)2(TCNQ)3] · 3H2O. These complexes were characterized by infrared, electronic absorption, variable temperature magnetic moments and electron paramagnetic studies. Magnetic moments increase with increase in temperature attributed to contribution from TCNQ, which has also been examined by electron paramagnetic resonance.  相似文献   

17.
Liu  B. P.  Tan  Z. C.  Nan  Z. D.  Liu  P.  Sun  L. X.  Xu  F.  Lan  X. Z. 《Journal of Thermal Analysis and Calorimetry》2003,71(2):623-628
A solid complex of rare-earth compounds with alanine, [ErY(Ala)4(H2O)8](ClO4)6 (Ala=alanine), was synthesized, and a calorimetric study and thermal analysis for it was performed through adiabatic calorimetry and thermogravimetry. The low-temperature heat capacity of [ErY(Ala)4(H2O)8](ClO4)6 was measured with an automated adiabatic precision calorimeter over the temperature range from 78 to 377 K. A solid-solid phase transition was found between 99 and 121 K with a peak temperature at 115.78 k. The enthalpy and entropy of the phase transition was determined to be 1.957 Kj mol-1, 16.90 j mol-1 k-1, respectively. Thermal decomposition of the complex was investigated in the temperature range of 40~550°C by use of the thermogravimetric and differential thermogravimetric (TG/DTG) analysis techniques. The TG/DTG curves showed that the decomposition started from 120 and ended at 430°C, completed in three steps. A possible mechanism of the thermal decomposition was elucidated. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

18.
The synthesis and characterization of cobalt(II), nickel(II) and copper(II) perchlorate complexes containing bis [(diphenylphosphinyl)methyl] [phenylphosphine oxide (RPPH), bis [(diphenylphosphinyl)methyl] ethyl phosphinate (RPOEt), and bis [(diphenylphosphinyl)methyl] phosphinic acid (RPOH) have been studied. The substituent at the central phosphorus atom of the ligand is responsible for the types of complexes formed. The new complexes [M(RPPh)2(ClO4)2.nH2O, [M(RPPh)3](ClO4)2.4H2O, [M(RPOEt)2](ClO4)2.2H2O, and [M(RPOH)3] (ClO4)2.nH2O are characterized as high spin and most of them have an octahedral or distorted octahedral geometry [M = Co(II), Ni(II), or Cu(II); n = 2?5]. The coordination of two P = O groups from one ligand to the metal has been proposed for most of the complexes formed. The coordination of all three P = O groups has been assumed for complexes [M(RPPh)2](ClO4)2.nH2O and [M(RPOEt)2](ClO4)2.2H2O.  相似文献   

19.
The reaction of 8-aminoquinoline (8-aq) with M(NO3)2 and M(ClO4)2 (where M = Zn, Cd and Hg) has synthesized complexes of the composition [M(8-aq)2(H2O)2](X)2 (X = NO3, ClO4) whereas MCl2 has isolated M(8-aq)Cl2 type non-ionic compounds. The reaction of M(OAc)2, 8-aq and NaN3/NH4CNS in a 1:1:2 mole ratio has separated polynuclear complexes of the composition [M(8-aq)(Y)2]n (Y = N3, NCS). The complexes have been characterized by spectroscopic data and have been structurally confirmed by single crystal X-ray diffraction study in some representative cases. The X-ray structure of [Zn(8-aq)2(H2O)2](NO3)2 shows C–H–π, and ππ interactions and forms a H-bonded sheet (with interactions between the oxygen of NO3 and C(9)–H of 8-aq/coordinated H2O). A novel one-dimensional cadmium(II) azido complex, [Cd(8-aq)(N3)2]n (9), in which the azido takes on an end-on (EO) bridging mode, has been synthesized and characterized. The presence of ππ interactions result in a supramolecular two-dimensional behaviour for the structure. The complexes are photoluminescent at room temperature.  相似文献   

20.
NaM2OH(SO3)2 · 1 H2O with M = Mg, Mn, Fe, Co, Ni, and Zn. A New Class of Basic Sulfites Hitherto unknown hydroxide sulfites of the type NaM2OH(SO3)2 · 1 H2O with M = Mg, Mn, Fe, Co, Ni, and Zn have been obtained by crystallization from aqueous sulfite solutions containing Na+ and M2+ ions. Crystal structure, IR and Raman data, and the results of thermoanalytical studies are reported and discussed. The hydroxide sulfites show a strongly anisotropic thermal expansion due to the layer structure and exhibit an unusually high thermal stability compared to other solid hydrates. The magnesium compound, for example, decomposes at 355°C. The crystal data of the triclinic compounds see “Inhaltsübersicht”.  相似文献   

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