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1.
Five chloroanilato-bridged manganese(II) binuclear complexes, [Mn2(CA)L4](ClO4)2, where L = 4,4′-dimethyl-2,2′-bipyridine (Me2-bpy), 5-methyl-1,10-phenanthroline (Me-phen), 5-chloro-1,10-phenanthroline (Cl-phen), 5-nitro-1,10-phenanthroline (NO2-phen) and 2,9-dimethyl-1,10-phenanthroline (Me2-phen), and CA represents the dianion of chloroanilic acid, have been synthesized and characterized by elemental analyses, molar conductivity and room temperature magnetic moment measurements, and by spectroscopy. It is proposed that these complexes have CA-bridged structures and consist of two manganese(II) ions in a distorted-octahedral environment. The complexes [Mn2(CA)(Me2-bpy)4](ClO4)2 (1) and [Mn2(CA)(Me-phen)4](ClO4)2 (2) were characterized by variable temperature magnetic susceptibility measurements (4–300 K) and the observed data were successfully simulated by an equation based on the spin Hamiltonian operator, Ĥ = −2 1 Ŝ 2, giving the exchange integral J = −1.98 cm−1 for (1) and J = −2.41 cm−1 for (2). This result indicates that there is a weak antiferromagnetic spin-exchange interaction between the two MnII ions within each molecule. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

2.
Six new μ-terephthalato iron(III) binuclear complexes have been prepared and identified: [Fe2(TPHA)(L)4]-(ClO4)4 [L = 2,2′-bipyridine (bpy); 1,10-phenanthroline (phen); 4,4′-dimethyl-2,2′-bipyridine (Me2bpy); 5-methyl-1,10-phenanthroline (Me-phen); 5-chloro-1,10-phenanthroline (Cl-phen) and 5-nitro-1,10-phenanthroline (NO2-phen)]; where TPHA = the terephthalate dianion. Based on the elemental analyses, molar conductance and magnetic moments of room-temperature measurements, and spectroscopic studies, extended TPHA-bridged structures consisting of two iron(III) ions, each in an octahedral environment, are proposed for these complexes. The [Fe2(TPHA)(Me-phen)4](ClO4)4 (1) and [Fe2(TPHA)(phen)4](ClO4)4 (2) complexes were characterized by variable temperature magnetic susceptibility (4–300 K) measurements and the observed data were successfully simulated by the equation based on the spin Hamiltonian operator, Ĥ = −2 1 Ŝ 2, giving the exchange integrals J = −1.05 cm−1 for (1) and J = −9.28 cm−1 for (2). This result indicates the presence of a weak antiferromagnetic spin-exchange interaction between the metal ions within each molecule. The influence of the terminal ligand methyl substituents on magnetic interactions between the metals is also discussed. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

3.
Cu11 complexes of 1,10-phenanthroline, disubstituted at the 2 and 9 positions or monosubstituted at the 2 position by phenyl moieties possessingortho substituents, were prepared and investigated by spectroscopic and electrochemical methods. The electronic spectral d-d band position varies from 14 500 to 13 200 cm−1. E.s.r. g values are between 2.256 to 2.283 and A between 164 to 117×10−4 cm−1. Thebis[2,9-di(o-substituted phenyl)-1,10-phenanthroline]Cu11 complexes undergo reversible one-electron electrochemical reduction (Cu11/Cu1) in the +0.536 to +0.825 V potential range versus s.c.e., whereas thebis[2-mono(o-substituted phenyl)-1,10-phenanthroline]Cu11 complexes undergo reduction in the +0.360 to +0.405 V range; the redox couple is found to be quasireversible. Emission studies on copper(I) complexes show that onlybis[2,9-di(o-tolyl)-1,10-phen]Copper(I) complex exhibits emission properties. Emission behaviour of other structurally similar compounds is explored. TMC 2555  相似文献   

4.
A novel asymmetric dinuclear gold(I) complex with 3,6-diethynylphenanthroline, 3,6-bis{(PPh3)–Au–C≡C}2-phen, has been synthesized from Au(PPh3)Cl (PPh3 = triphenylphosphine) and 3,6-diethynyl-1,10-phenanthroline. The asymmetrical dinuclear gold(I) complex, 3,6-bis{(PPh3)–Au–C≡C}2-phen, demonstrated a weak phosphorescence assignable to the metal-perturbed 3 ππ* transition in the long wavelength region compared to an intense emission of the symmetrical dinuclear complex with 3,8-diethynylphenanthroline, 3,8-bis{(PPh3)–Au–C≡C}2-phen. A similar tendency of phosphorescent bands for the mononuclear gold(I) complexes with 5-ethynylphenanthroline, 5-{(PPh3)–Au–C≡C}-phen, and 3-ethynylphenanthroline, 3-{(PPh3)–Au–C≡C}-phen was observed. The absorption bands assignable to the ππ*(C≡Cphen) transition and phosphorescent emission assignable to the metal-perturbed 3 ππ* transition for these four gold(I) complexes were reasonably consistent with the results calculated by DFT and TD-DFT.  相似文献   

5.
Three novel heterobinuclear complexes have been prepared and identified as [Cu(oxap)Ni(L)2](ClO4)2·ξH2O, where oxap denotes theN,N′-bis(2-aminopropyl)oxamido dianion and L denotes 2,2′-bipyridine (bipy), 1,10-phenanthroline (phen) or 5-nitro-1,10-phenanthroline (NO2-phen). The crystal structure of [Cu(oxap)Ni(phen)2]-(ClO4)2·2H2O has been determined. Crystal data: triclinic, space group , a=12.079 (6), b=12.409 (4), c=17.261 (8) ?, α=70.91 (2), β=86.72 (4), γ=89.19 (3)o. At room temperature, Z=2. The CuII is in a square planar environment and the NiII is in an octahedral environment. The Cu−Ni distance is 5.292 ?. The temperature dependences of the magnetic susceptibilities of [Cu(oxap)Ni(phen)2]-(ClO4)2·2H2O and [Cu(oxap)Ni(bipy)2](ClO4)2 have been studied in the 4.2–300 K range, giving the exchange integral J=−92.4 cm−1 for bipy and J=−94.3 cm−1 for phen. These results are commensurate with antiferromagnetic interactions between the adjacent metal ions.  相似文献   

6.
Three cyanide-bridged dodecanuclear macrocyclic wheel-like complexes [Cr(bpmb)(CN)2]6[Mn(5-Brsalpn)]6·12H2O (1), [Co(bpmb)(CN)2]6[Mn(5-Brsalpn)]6·12H2O (2) and [Co(bpmb)(CN)2]6[Mn(5-Clsalpn)]6·24H2O·8CH3CN (3) [bpmb2−= 1,2-bis(pyridine-2-carboxamido)-4-methylbenzenate dianion; 5-Brsalpn2− = N,N′-propylenebis(5-bromosalicylideneaminato) dianion; 5-Clsalpn2− = N,N′-propylenebis(5-chlorosalicylideneaminato) dianion] have been synthesized and their crystal structures and magnetic properties have been investigated. The three compounds are structurally isomorphous and consist of alternating Mn(III)-Schiff base cations and [M(bpmb)(CN)2] anions, generating cyanide-bridged nanosized dodecanuclear macrocyclic structures with an approximate diameter of 2 nm. The study of the magnetic properties of complex 1 reveals an antiferromagnetic interaction between the Cr(III) and Mn(III) ions through the cyanide bridges. A best-fit to the magnetic susceptibility of the complex leads to a magnetic coupling constant of J CrMn = −2.65(6) cm−1 on the basis of a one-dimensional alternating chain model with the Hamiltonian $ H = - J_{CrMn} \sum\limits_{i = 0}^N {S_i \cdot S_{i + 1} } $ H = - J_{CrMn} \sum\limits_{i = 0}^N {S_i \cdot S_{i + 1} } .  相似文献   

7.
Two multidentate ligands: N,N′-di-(propionic acid-2′-yl-)-2,9-diaminomethyl-1,10-phenanthroline (L1) and N,N′-di-(3′-methylbutyric acid-2′-yl-)-2,9-diaminomethyl-1,10-phenanthroline (L2) were synthesized. The hydrolytic kinetics of p-nitrophenyl phosphate (NPP) catalyzed by complexes of L1 and L2 with La(III), Gd(III) have been studied. Both LnL and LnLH−1 have been examined as catalysis for the hydrolysis of NPP in aqueous solution at 298 K, I = 0.10 mol dm−3 KNO3 at the pH range 7.4–9.1, respectively. Kinetic studies show that both LnL and LnLH−1 have catalytic activity, but LnLH−1 is more active than LnL in the hydrolysis of NPP. The second-order rate constants for the hydrolysis of NPP are kGdL1H−1 = 0.01399 mol−1 dm3 s−1, kGdL1 = 0.0000110 mol−1 dm3 s−1 for complexes GdL1H−1 and GdL1, respectively. A new mechanism was proposed for the hydrolysis of NPP catalyzed by LnL and LnLH−1.  相似文献   

8.
We have synthesized high-spin mixed-ligand Mn2+ complexes Mn(S2COR)2L where R=i−C3H7, i−C4H9; [L=1,10-phenanthroline (Phen), 2,2′-bipyridyl (2,2′-Bipy), 4,4′-bipyridyl (4,4′-Bipy)]. As solids, the compounds are stable to oxidation by atmospheric oxygen. An X-ray structural study of the [Mn(S2COC3H7−i)2(2,2′-Bipy)] complex was carried out. The structure is composed of discrete monomeric molecules. The corrdination polyhedron of the Mn atom is a distorted [4S+2N] octahedron. The molecules are bonded by van der Waals interactions. Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 2, pp. 106–111, March–April, 1994. Translated by T. Yudanova  相似文献   

9.
A new inorganic-organic hybrid solid, [Cd(phen)(H2O)4](ClO4)Cl · H2O (phen = 1,10-Phenanthroline), has been synthesized under reflux conditions and characterized by single-crystal X-ray diffractions, ICP analysis, elemental analysis and electrical analysis. The compound crystallizes in the orthorhombic, space group a = 0.88361(10) ?, b = 1.8492(2) ?, c = 2.2157(2) nm, Z = 8, Dc = 1.899 g cm−3. Furthermore, electrical studies for complex have also been reported in this article.  相似文献   

10.
The water-soluble Ni(II) complex, [Ni(bipy)2(phen-dione)](OAc)2·2H2O (bipy = 2,2′-bipyridine and phen-dione = 1,10-phenanthroline-5,6-dione) has been synthesized and characterized by physico-chemical and spectroscopic methods. The binding interactions of this complex with calf thymus DNA (CT-DNA) were investigated using fluorimetry, spectrophotometry, circular dichroism and viscosimetry. In fluorimetric studies, the enthalpy and entropy of the reaction between the complex and CT-DNA showed that the reaction is exothermic (ΔH = −123.9 kJ mol−1; ΔS = −323.5 J mol−1 K−1). The competitive binding studies showed that the complex could not release methylene blue completely. The complex showed absorption hyperchromism in its UV–Vis spectrum with DNA. The calculated binding constant, K b obtained from UV–Vis absorption studies was 2 × 105 M−1. Moreover, the complex induced detectable changes in the CD spectrum of CT-DNA, as well as changes in its viscosity. The results suggest that this nickel(II) complex interact with CT-DNA via a groove-binding mode.  相似文献   

11.
A new 2D (two-dimensional) coordination polymer, [Fe(μ4-bta)o.5(phen)(OH)]n (1), has been hydrothermally synthesized with FeCl3 6H2, Na4bta (h4bta = 1,2,4,5-benzentetracarboxylic acid), 1,10-phen (1,10-phenanthroline) and H2O as raw materials. The crystals of the compound belong to monoclinic P21/n space group, a = 1.0129(2) nm, b = 0.9265(2) nm, c = 1.5696(3) nm, β=91.37(3)°V=1.4721(5) nm3,Z=3, final R1=0.0292, wR 2=0.0798 for 2572 [/>2σ(/)] observed reflections. The result of structure determination shows that in the compound each bta ligand is connected with four Fe3, forming a new μ4-coordination mode. Four deprotonated carboxylic groups of bta link to Fe3 ions alternatively through monodentate and bidentate coordination fashion, constructing 2D layer network. The measurement of variable temperature magnetic susceptibility indicates that there exist antiferromagnetic interactions between Fe3 ions in the compound. The TGA spectrum displays relatively fine thermal stability of the compound. In addition, IR and UV-Vis spectra of compound 1 have also been measured.  相似文献   

12.
Two novel oxamidato-bridged Mn[Cu(PMoxd)]3(ClO4)2 (1) Ni[Cu(PMoxd)]3(ClO4)2 (2) tetranuclear complexes were prepared and characterized by i.r., e.p.r., electronic spectra, cyclic voltammograms, and magnetic properties. The magnetic analysis was carried out by means of the theoretical expression of the magnetic susceptibility deduced from the spin Hamiltonian H=−2JSM(SCu1+ SCu2 + SCu3) (M=Mn, Ni), leading to J=−20.4 cm−1; −121.1 cm−1 for complexes (1) and (2) respectively. Magnetic measurements indicate that the overall magnetic behavior of the tetranuclear species are antiferromagnetic.  相似文献   

13.
A novel ligand (H2L), diethylenetriamine-N,N′,N′′-triacetylisoniazide N,N′′-bisacetic acid, and its four non-ion transition metal complexes, ML · nH2O (M = Mn, n = 4; M = Co, Ni, n = 2; M = Cu, n = 1), have been synthesized and characterized on the basis of elemental analysis, molar conductivity, 1H-NMR, FAB-MS, TG-DTA analysis and IR spectrum. In addition, relaxivity (R1) of the complexes was determined, the relaxivity of MnL, CoL, NiL, CuL as well as Gd(DTPA)2− used as a control are 6.94, 2.79, 2.52, 1.59 and 4.34 l mmol−1 s−1, respectively. The relaxivity of MnL is larger than that of Gd(DTPA)2−. The results show that the complex of MnL may be a potential MRI contrast agent.  相似文献   

14.
The new binuclear complex [(1,10-phen)2Zn22-OOCR)22-OOCR)2]·4THF (2·4THF, RCOO is the β-naphthoate anion) was synthesized. According to the single-crystal X-ray diffraction study, a one-dimensional supramolecular structure is formed through intra- and intermolecular π-π interactions between the phenanthroline moieties of complex 2. Compound 2 exhibits photoluminescence properties at room temperature.  相似文献   

15.
Summary Reactions of bis(1-oxopyridine-2-thione) NiII or CuII with 2,2-bipyridine (bipy) or 1,10-phenanthroline (phen) yield complexes of stoichiometry: Ni(C5H4NOS)2L {L = bipy, two isomers: (1) and (2), L = phen, one isomer (3)} and Cu(C5H4NOS)2(phen)·0.75CHCl3 (4). The spectroscopy (i.r., u.v.-vis., e.s.r.) and magnetism studies of the above complexes are described. On the basis of conductivity, the CuII-phen complex has been formulated as [Cu(C5H4NOS)(phen)2][Cu(C5H4NOS)3]·1.5CHCl3 (4). The vis. absorption spectra support similar octahedral structures for the minor bipy isomer (2) and for the NiII-phen complex [(3)], whereas the major isomer [(1)] has a different structure. The e.s.r. spectrum of the CuII-phen complex (4) is commensurate with an elongated octahedral structure. New methods for the preparation and spectroscopy of M(C5H4NOS)2 (M = Mn, Ni, Cu or Zn) compounds have been investigated.  相似文献   

16.
A novel tetradentate nitrogen donor [N4] macrocyclic ligand, i.e. 3,5,13,15,21,22-hexaaza-2,6,12,16-tetramethyl-4,14-dithia-tricyclo[15.3.1.1(7–11)]docosane-1(21),2,5,7,9,11(22),12,15,17,19-decaene, has been synthesized. Mn(II), Co(II), Ni(II) and Cu(II) complexes with this ligand have been prepared and subjected to elemental analyses, molar conductance measurements, magnetic susceptibility measurements, mass, 1H-n.m.r. (Ligand), i.r., electronic, and e.p.r. spectral studies. On the basis of molar conductance the complexes may be formulated as [M(L)X2] and [Ni(L)]X2 [where M = Mn(II), Co(II) and Cu(II), and X = Cl and NO3] due to their nonelectrolytic nature in dimethylsulphoxide (DMSO). All the complexes are of the high spin type and are six coordinated. On the basis of i.r., electronic and e.p.r. spectral studies an octahedral geometry has been assigned to Mn(II) and Co(II), square planar for Ni(II) complexes, and tetragonal for Cu(II) complexes. The antimicrobial activities of the ligand and its complexes, as growth inhibiting agents, have been screened in vitro against several species of bacteria and plant pathogenic fungi.  相似文献   

17.
The catalysts of hexaaluminate (BaMnxAl12-xO19-δ , x = 1.0, 2.0, 3.0, 4.0) to be used in methane combustion have been successfully synthesized by co-precipitation method and supercritical drying. The crystalline structure and surface area of catalyst were characterized by X-ray diffraction (XRD) and nitrogen adsorption analysis of BET method. BET analysis revealed that the preparing and drying method proposed here provides stable materials with higher surface area of 51.4 m2/g in comparison to materials prepared using conventional ambient drying method for BaMnxAl12?xO19-δ calcined at 1200℃ under oxygen. XRD analysis indicated that formation of a pure single phase BaMnxAl12-xO19-δ occurred up to x = 3 in the case of Mn-substituted barium hexaaluminates. Incorporation of Mn in excess leads to BaAl2O4 phase formation. As far as the valence state of Manganese ions was concerned, the introduced Mn ions were either divalent or trivalent. The first Mn ions were introduced in the matrix essentially as Mn2 and only for BaMn3Al9O19-δ does manganese exist exclusively as Mn3 ; the higher the Mn concen- tration, the higher the proportion of Mn3 . Catalytic activity for methane combustion has been measured for Mn-substituted barium hexaaluminates, light-off temperature was observed in the 512-624℃ range. The highest activity was obtained for catalysts containing 3 Mn ions per unit cell, which reveals that the BaMnxAl12-xO19-δ catalyst was a promising methane combustion catalyst with high activity and good thermal stability. Temperature programmed reduction (TPR) under hydrogen has been used to correlate the catalytic activity with the amount of easily reducible species.  相似文献   

18.
Two coordination polymers, {[Mn(1,10-phen)2(3,4-H2bptc)]?·?(H2O)}2 n (1) and {[Co2(1,10-phen)(3,4-bptc)(H2O)2]?·?H2O} n (2) (3,4-H4bptc = 3,3′,4,4′-biphenyltetracarboxylic acid, 1,10-phen?=?1,10-phenanthroline), have been prepared and structurally characterized. In both compounds, 3,4-H2bptc2– and 3,4-bptc4? exhibit different coordination modes and lead to various architectures. Compound 1 displays 1-D zigzag chains constructed with hydrogen bonds. Compound 2 exhibits a 2-D layer constructed from bpta4? between the dinuclear Co(II) units. The thermal stabilities and magnetic properties are also reported. In addition, 1 was explored as a luminescent material. The carboxylic oxygen atoms act as H-bond acceptors and donors forming a 1-D ladder-like arrangement.  相似文献   

19.
Complexes of 1,10-o-phenanthroline (o-phen)-NiII and CuII with dithiocarbamates derived from -amino acids (glycine, phenylalanine, alanine, methionine and tryptophan) were synthesized and characterized by chemical analysis, spectral and thermal studies and by biological screening; the complexes are non-electrolytes. The empirical formula are [Ni(o-phen)2(aadtc)] and [Cu2(o-phen)2(phaladtc)(H2O)2Br2] where, aadtc = glycinyl-, phenylalaninyl-, alaninyl-, methioninyl- and tryptophanyldithiocarbamate and phaladtc = phenylalaninyldithiocarbamate. The structure of these complexes is probably octahedral. Molecular association through hydrogen bonding between the —NH and the carboxylate groups is proposed for the NiII complexes. The CuII complex is dimeric with the phenylalaninyldithiocarbamate acting as a bridge.  相似文献   

20.
The novel ternary solid complex Gd(C5H8NS2)3(C12H8N2) has been obtained from the reaction of hydrous gadolinium chloride, ammonium pyrrolidinedithiocarbamate (APDC), and 1,10-phenanthroline (o-phen · H2O) in absolute ethanol. The complex was described by an elemental analysis, TG-DTG, and an IR spectrum. The enthalpy change of the complex formation reaction from a solution of the reagents, Δr H m ϑ (sol), and the molar heat capacity of the complex, c m , were determined as being − 15.174 ± 0.053 kJ/mol and 72.377 ± 0.636 J/(mol K) at 298.15 K by using an RD496-III heat conduction microcalorimeter. The enthalpy change of a complex formation from the reaction of the reagents in a solid phase, Δr H m ϑ (s), was calculated as being 52.703 ± 0.304 kJ/mol on the basis of an appropriate thermochemical cycle and other auxiliary thermodynamic data. The thermodynamics of the formation reaction of the complex was investigated by the reaction in solution. Fundamental parameters, the activation enthalpy (ΔH ϑ ), the activation entropy (ΔS ϑ ), the activation free energy (ΔG ϑ ), the apparent reaction rate constant (k), the apparent activation energy (E), the preexponential constant (A), and the reaction order (n), were obtained by the combination of the thermochemical data of the reaction and kinetic equations, with the data of thermokinetic experiments. The constant-volume combustion energy of the complex, Δc U, was determined as being −17588.79 ± 8.62 kJ/mol by an RBC-II type rotatingbomb calorimeter at 298.15 K. Its standard enthalpy of combustion, Δc H m ϑ , and standard enthalpy of formation, Δf H m ϑ , were calculated to be −17604.28 ± 8.62 and −282.43 ± 9.58 kJ/mol, respectively. The text was submitted by the authors in English.  相似文献   

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