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1.
A new Schiff base ligand C19H13NO5(H2L) was synthesized using 2-aminoterephthalic acid and 2-hydroxy-1-naphthaldehyde. A complex of this ligand [Cu(C19H11NO5)(C2H6O)] n was synthesized and characterized by IR, UV, fluorescence spectroscopy and X-ray diffraction single-crystal analysis. The crystal crystallizes in the monoclinic system, space group Pbca with a = 8.7745(18), b = 18.613(4), c = 24.644(5) Å, V = 4024.9(14) Å3, Z = 8, F(000) = 1816, S = 1.009, ρ calcd = 1.462 g cm?3, μ = 1.122 mm?1, the final R = 0.0477 and wR = 0.1594 for 4609 observed reflections (I > 2σ(I)). The Cu(II) is five-coordinated by one N atom and two O atoms from the Schiff base ligand and two carboxylate O atoms from another two ligands to form a distorted square-pyramidal geometry. Each ligand serves as a bridging ligand to link Cu2+ ions, leading to a two-dimensional coordination polymer. The fluorescence properties of the ligand and complex were also studied. The ligand shows strong fluorescence, and the fluorescence intensity is weakened after the Cu(II) complex formed.  相似文献   

2.
X-ray structural analysis has been performed for two complex compounds: Cu(en)2(o-HB)2H2O (I) (a = 16.873(4) Å, b = 8.713(2) Å, c = 14.803(3) Å, β = 91.15(2)°, V = 2175.8(8) Å3, C2/c, Z = 4, R(F) = 0.0263, 1516 reflections with I > 3σ (I)) and [Cu(en)2(OH2)2]2+(o-AB?)2 (II) (a = 7.488(5) Å, b = 22.122(8) Å, c = 7.856(5) Å, β = 118.77(2)°, V = 1140.7(11) Å3, P21/n, Z = 2, R(F) = 0.0432, 1684 reflections with I > 3σ(I)) synthesized under identical conditions (en is ethylenediamine, o-HB is o-hydroxybenzoate, and o-AB is o-aminobenzoate). Although the compounds were assumed to have similar structures and the Cu-Lig bond lengths and the cis and trans angles are acceptable for an octahedral structure, the geometric parameters of o-HB suggest that the copper atom has a plane square environment.  相似文献   

3.
A complex [Zn(C8H7O3)2(H2O)2] (C8H8O3 is vanillin) has been synthesized and characterized by IR, elemental analysis, and X-ray diffraction single-crystal analysis. The crystals are monoclinic, space group C2/c, a = 22.236(8) Å, b = 10.594(2) Å, c = 7.8190(16) Å, α = 89.90(3)°, β = 106.87(4)°, γ = 89.99(3)°, V = 1762.6(8) Å3, Z = 4, F(000) = 832, S = 1.079, ρ c = 1.521g cm?3, R = 0.0221, R w = 0.0604, μ = 1.433 mm?1. The Zn2+ ion is six-coordinated with a distorted octahedron geometry. The complex forms a three-dimensional network through intermolecular hydrogen bonds. The thermal decomposition kinetics of the complex for the second stage was studied under non-isothermal conditions by the TG and DTG methods. The kinetic equation can be expressed as dα/dt = Ae?E/RT 2(1 ? α)[1 ? ln(1 ? α)]1/2. The kinetic parameters (E, A), activation entropy ΔS , and activation free-energy ΔG were also gained.  相似文献   

4.
The structural stabilities, bonding nature, electronic properties, and aromaticity of bare iridium trimers \(\rm{Ir}_3^{+/-}\) with different geometries and spin multiplicities are studied at the DFT/B3LYP level of theory. The ground state of the \(\rm{Ir}_3^{+}\) cation is found to be the 3A2 (C2v) triplet state and the ground state of the \(\rm{Ir}_3^{-}\) anion the 5A2 (C2v) quintet state. A detailed molecular orbital (MO) analysis indicates that the ground-state \(\rm{Ir}_3^{+}\) ion (C2v, 3A2) possesses double (σ and partial δ) aromaticity as well as the ground-state \(\rm{Ir}_3^{-}\) ion (C2v, 5A2). The multiple d-orbital aromaticity is responsible for the totally delocalized three-center metal-metal bond of the triangular Ir3 framework. \(\rm{Ir}_3^{-}\) (C2v, 1A1) structure motif is perfectly preserved in pyramidal Ir3M0/+ (Cs, 1A′) and bipyramidal \(\rm{Ir}_3M_2^{+/3+}\) (C2v, 1A1) (M = Li, Na, K and Be, Ca) bimetallic clusters which also possess the corresponding d-orbital aromatic characters.  相似文献   

5.
A new cobalt(II,III) complex, [CoIIIL2]2[Co 2 II (HL)2(OH2)2(CH3OH)2] ? 2H2O (I) and a new iron(III) complex, [FeIII(HL)2](NO3) (II), where L2– and HL are the dianionic and monoanionic form of N'-(2-hydroxybenzylidene)-3-methylbenzohydrazide, respectively, have been prepared and characterized by elemental analyses, infrared and UV-Vis spectroscopy and single-cyrstal X-ray diffraction (CIF files CCDC nos. 1417971 (I), 1417979 (II)). Complex I crystallizes in the monoclinic space group P21/n with unit cell dimensions a = 16.1665(9), b = 14.5692(8), c = 19.086(1) Å, β = 96.347(1)°, V = 4467.9(4) Å3, Z = 2, R 1 = 0.0521, and wR 2 = 0.1411. Complex II crystallizes in the orthorhombic space group Pbcn with unit cell dimensions a = 12.475(1), b = 12.202(1), c = 18.859(2) Å, V = 2870.8(4) Å3, Z = 4, R 1 = 0.0796, and wR 2 = 0.1981. The metal atoms in the complexes are in octahedral coordination. Crystals of the complexes are stabilized by hydrogen bonds. The efficiency of the aroylhydrazone and the two complexes was evaluated against B. subtilis, S. aureus, E. coli, P. fluorescence, C. albicans and A. niger, with the complexes demonstrating enhanced activity relatively to the free ligand.  相似文献   

6.
A convenient method is suggested for calculating thermally averaged powers of the normal vibrational coordinates Q i by iteratively solving the Bloch integral equation with an anharmonic function of potential energy using multidimensional Hermite polynomials. Analytical formulas of the first approximation regarding anharmonicity constant have been obtained for the following moments of thermally averaged density: 〈Q 1〉, 〈 Q 1 2 〉, 〈Q 1 Q 2〉, 〈Q 1 3 〉 〈Q 1 3 〉, 〈Q 1 Q 2 Q 3〉, 〈Q 1 4 〉, 〈Q 1 2 Q 2 2 〉, 〈Q 1 Q 2/3〉, 〈Q 1 Q 2 Q 3 2 〉, 〈 Q 1 Q 2 Q 3 Q 4〉.  相似文献   

7.
In Vitro Binding of Furadan to Bovine Serum Albumin   总被引:1,自引:0,他引:1  
Under physiological conditions, the interaction between furadan (FRD) and bovine serum albumin (BSA) was investigated by spectroscopy including fluorescence emission, UV-visible absorption, scattering, circular dichroism (CD) spectra, synchronous and three-dimensional fluorescence spectra. The observed binding constant K b and the number of binding sites n were determined by the fluorescence quenching method. The distance r between donor (BSA) and acceptor (FRD) was obtained according to the Förster theory of non-radiation energy transfer. The enthalpy change (ΔH θ ), Gibbs energy change (ΔG θ ) and entropy change (ΔS θ ) at four different temperatures were calculated. The process of binding was proposed to be a spontaneous process since the ΔG θ values were negative. The positive ΔS θ and ΔH θ values indicated that the interaction of FRD and BSA was driven mainly by hydrophobic interactions. The addition of FRD to BSA solutions leads to enhancement in scattering intensity, exhibiting the formation of an aggregate in solution. CD spectra, synchronous and three-dimensional fluorescence spectra were used to measure the structural change of BSA molecules with FRD present.  相似文献   

8.
The syntheses and crystal structures of the layered coordination polymers M(C8H8NO2)2 [M = Mn (1), Co (2), Ni (3) and Zn (4)] are described. These isostructural compounds contain centrosymmetric trans-MN2O4 octahedra as parts of infinite sheets; the ligand bonds to three adjacent metal ions in μ3-N,O,O′ mode from both its carboxylate O atoms and its amine N atom. In each case, weak intra-sheet N–H?O and C–H?O hydrogen bonds may help to consolidate the structure. Crystal data: 1, C16H16MnN2O4, M r = 355.25, monoclinic, P21/c (No. 14), a = 10.6534(2) Å, b = 4.3990(1) Å, c = 15.5733(5) Å, β = 95.1827(10)°, V = 726.85(3) Å3, Z = 2, R(F) = 0.026, wR(F 2) = 0.067. 2, C16H16CoN2O4, M r = 359.24, monoclinic, P21/c (No. 14), a = 10.6131(10) Å, b = 4.3374(4) Å, c = 15.3556(17) Å, β = 95.473(4)°, V = 703.65(12) Å3, Z = 2, R(F) = 0.041, wR(F 2) = 0.091. 3, C16H16N2NiO4, M r = 359.02, monoclinic, P21/c (No. 14), a = 10.6374(4) Å, b = 4.2964(2) Å, c = 15.2827(8) Å, β = 95.9744(14)°, V = 694.66(6) Å3, Z = 2, R(F) = 0.028, wR(F 2) = 0.070. 4, C16H16N2O4Zn, M r = 365.68, monoclinic, P21/c (No. 14), a = 10.6385(5) Å, b = 4.2967(3) Å, c = 15.2844(8) Å, β = 95.941(3)°, V = 694.89(7) Å3, Z = 2, R(F) = 0.038, wR(F 2) = 0.107.  相似文献   

9.
A novel samarium compound, [Sm(Phen)2(H2O)5]2(Phen)2(Bipy)Cl6 · 7H2O (I) (Phen = 1,10-phenanthroline and Bipy = 2,2'-bipyridine), was prepared by a solvothermal reaction. The crystal structure of I was characterized by X-ray single-crystal diffraction method (CIF file CCDC no. 1025736). Compound I is an isolated structure with the samarium ions possessing a nine-coordinated distorted monocapped square antiprism geometry. There are abundant hydrogen bonding and π–π stacking interactions which connect the molecules together to yield a three-dimensional (3D) supramolecular structure. The fluorescence spectra data reveals that I can display the characteristic emission 4G5/26H J transitions (J = 5/2, 7/2, 9/2 and 11/2, respectively) of Sm3+ ions.  相似文献   

10.
The formation of chloro- and azidocomplexes of VO2+(IV) is investigated in acetonitrile (AN), propanediol-1,2-carbonate (PDC), trimethyl phosphate (TMP) by spectrophotometric, potentiometric and conductometric methods. The following coordination forms are indicated: [VOCl]+ inAN, PDC andDMSO), [VOCl2] (inAN, PDC andTMP), [VOCl3]? (inPDC andTMP[?]), [VOCl4]2? (inAN, PDC andTMP); [VON3]+ (inAN, PDC andDMSO), [VO(N3)2] (inAN, PDC, TMP andDMSO), [VO(N3)2+n]n? (inAN, PDC, TMP andDMSO). The results are interpreted by the donor numbers and sterical properties of the solvent molecules.  相似文献   

11.
Addition of chloride ions to the hexasolvated ions of Ti(III), V(III) and Cr(III) in propandiol-1,2-carbonate (PDC) and trimethylphosphate (TMP) may lead to the following complexes: [TiCl]2+ (inPDC), [TiCl2]+ (inTMP), TiCl3 (inPDC andTMP, low solubility inTMP), [TiCl4]? (inPDC andTMP?), [TiCl6]3? (inPDC); [VCl]2+ (inPDC andTMP), VCl3 (inPDC andTMP, low solubility inTMP), [VCl4]? (inPDC); [CrCl]2+ (inTMP), [CrCl2]+ (inPDC), CrCl3 (inPDC andTMP), [CrCl4]? (inPDC).  相似文献   

12.
Cobalt (III) complexes with N-salicylidene-2-hydroxy-5-bromobenzylamine (H2sbba) and N-salicylidene-2-hydroxy-5-chlorobenzylamine (H2scba), [n-(C4H9)4N][Co(sbba)2] (I) and [n-(C4H9)4N][Co(scba)2] (II), were synthesized. The crystal structure of II was determined by the single-crystal X-ray diffraction method at 90 K confirming its crystallization in the monoclinic space group P21/n with a = 11.729(2) Å, b = 16.901(3) Å, c = 21.483(4) Å, β = 98.840(4)°, V = 4208.2(14) Å3, Dx = 1.295 g cm?3, and Z = 4. The R1 [I > 2σ(I)] and wR2 (all data) values of 0.0664 and 0.1920, respectively, for all 9521 independent reflections. The compound is composed of a tetra(n-butyl)ammonium cation and an octahedral cobalt(III) complex anion with two scba2? ligands in a meridional fashion. The electronic spectral features of I and II are consistent with the octahedral cobalt(III) ion with an N2O4 donor set.  相似文献   

13.
A sample of magnesio-ferri-hornblendite, a potential new mineral of the amphibole supergroup, was studied by X-ray diffraction and IR spectroscopy. The crystal chemical formula is (Z = 2): AK0.04M(4) (Ca1.92Na0.08) C[M(1)(Mg1.78Fe0.224+) M(2)(Mg1.62Fe0.263+Al0.12) M(3)(Mg0.64Fe0.322+Mn0.04)] [T(Si7.44Al0.56)O22] W(OH)2. The monoclinic unit cell parameters are a = 9.855(1) Å, b = 18.084(1) Å, c = 5.289(1) Å, β = 104.853(2)°; V = 911.1(2) Å3; space group C2/m; Z = 2. The crystal structure was refined to R = 2.82% in the anisotropic approximation for atomic displacement parameters using 1166 reflections with I > 2σ(I). The magnesio-ferri-hornblendite structure is generally similar to the structures of other monoclinic calcium amphiboles, and its key distinctive features are the predominance of Мg among C2+ cations and Fe3+ among C3+ cations.  相似文献   

14.
A DFT method with the B3LYP functional and the 6-311++G(d,p) diffuse basis set is used to predict geometries, relative stabilities, electronic structures, and the bonding of closo- and nido-GamBnmH n 2? , GemBnmH n m?2 , and AsmBnmH n 2 m?2 (n = 10, 12 and m = 1, 2) Clusters are obtained by replacing BH with isolobal GaH, GeH+, and AsH2+ fragments, keeping the same skeleton electron pairs (SEP). Based on the polyhedral skeletal electron pairs theory (PSEPT), closo and nido structures are predicted and can be of significant interest for experimentalists working in the field of heteroboranes. Different cluster stabilities are studied according to Gimarc′s and Williams′ rules, where our calculations show that the monosubstituted clusters deviate from these rules, giving rise to open structures. As2B8H n 2+ as 10-vertex structures lead to nido-type clusters, however, GemBnmH n m?2 (n = 10, 12 and m = 1, 2) give rise to closo isomers with close energies. All optimized structures exhibit large HOMO–LUMO gaps suggesting a good kinetic stability, thus predicting their isolation and characterization.  相似文献   

15.
The treatment of o-diaminobenzene with Zn ( OAc )2 · 2H2O in alcohol results in the formation of mononuclear bis(o-diaminobenzene)diacetate Zinc, Zn[C8H11N2O2]2. Its structure was determined by X-ray diffraction analysis. The complex is also characterized by elemental analysis, 1H NMR and IR. The crystal is monoclinic space group C2, parameters: a = 16.297(5), b = 4.775(3), c = 11.664(5) Å, β = 97.646(5)°, λ = 1.54184 Å, V = 899.6(7) Å3, Z = 2, ρ c = 1.476 g/cm3, M r = 399.75, F(000) = 416.0, R 1 = 0.0594, wR 2 = 0.1439 for 995 observed reflections with I > 2σ(I).  相似文献   

16.
The temperature dependence of the heat capacity C p o of the [(Me3Si)7C60]2 fullerene complex was measured for the first time using precision adiabatic vacuum calorimetry over the temperature range 6.7–340 K and high-accuracy differential scanning calorimetry at 320–635 K. For the most part, the error in the C p o values was about ±0.5%. An irreversible endothermic effect caused by the splitting of the dimeric bond between fullerene fragments and the thermal decomposition of the complex was observed at 448–570 K. The thermodynamic characteristics of this transformation were calculated and analyzed. Multifractal analysis of the low-temperature (T < 50 K) heat capacity was performed, and conclusions were drawn concerning the character of the heterodynamicity of the structure. The experimental data obtained were used to calculate the standard thermodynamic functions C p o (T), H o (T) ? H o (0), S o (T) ? S o (0), and G o (T) ? H o (0) over the temperature range from T → 0 to 445 K and estimate the standard entropy of formation of the compound from simple substances at 298.15 K. The standard thermodynamic properties of [(Me3Si)7C60]2 are compared with those of the (C60)2 dimer, the [(η6-Ph2)2Cr]+[C60]?? fulleride, and the initial C60 fullerene.  相似文献   

17.
The chloro systems of Mn2+ and Fe3+ were investigated in acetonitrile (AN), propanediole-1,2-carbonate (PDC) and trimethylphosphate (TMP) by spectrophotometric, potentiometric and conductometric methods. The following coordination forms seem to be present: MnCl2 (inAN, PDC andTMP), [MnCl4]2? (tetrahedral inAN, octahedral inTMP), [MnCl6]4? (octahedral inPDC andTMP); [FeCl]2+ (tetrahedral inAN andPDC), [FeCl2]+ (tetrahedral inTMP), FeCl3 (tetrahedral inAN andPDC), [FeCl4]? (tetrahedral inAN, PDC andTMP).  相似文献   

18.
The crystal structures of cobalt(II) Schiff base complex (CoIIL2 · H2O) and Schiff base ligand 3,5-dichlorosalicylidene-2-chlorophenylmethylamine (HL) have been determined by single-crystal X-ray analysis. The geometry around cobalt in CoIIL2 · H2O is distorted tetrahedral. CoIIL2 · H2O crystallizes in the monoclinic system, in space group C2/c, with crystallographic parameters: a = 12.9143(16) Å, b = 8.8326(16) Å, c = 25.115(3) Å, β = 92.791(10)°, V = 2861.4(7) Å3, Z = 4, F(000) = 1420, and the final R indices (I > 2σ(I)) are R 1 = 0.0440, wR 2 = 0.1272. HL crystallizes in the monoclinic system, in space group P21/c, with crystallographic parameters: a = 11.9764(15), b = 8.2331(10), c = 14.2211(17) Å, β = 98.723(6)°, V = 1386.0(3) Å3, Z = 4, F(000) = 640, and the final R indices (I > 2σ(I)) are R 1 = 0.0397, wR 2 = 0.1018.  相似文献   

19.
Two coordination polymers, {[Cd(L1)2(L2)] · 0.25H2O} n (I) and {[Cd(L1)(L3)H2O] · 2H2O} n (II) (L1 = 2-pyrimidineamidoxime, L2 = 4-sulfobenzoate dianion and L3 = 5-sulfosalicylate dianion), has been synthesized and structurally characterized by single-crystal X-ray diffraction (CIF files CCDC nos. 1565646 (I) and 1565728 (II)). Complex I crystallizes in monoclinic space group P21/n with a = 10.1462(3), b = 16.0152(5), c = 14.0349(5) Å, β = 93.267(3)°, V = 2276.87(13) Å3, C68H66N32O29S4Cd4, M = 2373.36, ρcalcd = 1.731 g/cm3, μ(MoKα) = 1.109 mm?1, F(000) = 1186, GOOF = 0.806, Z = 1, the final R1 = 0.0287 and wR2 = 0.0733 for I > 2σ(I). Complex II crystallizes in monoclinic space group P21 with a = 6.882(2), b = 17.138(2), c = 7.883(2) Å, β = 103.83(3)°, V = 902.8(4) Å3, C12H16N4O10SCd, M = 520.75, ρcalcd = 1.916 g/cm3, μ(MoKα) = 1.388 mm?1, F(000) = 520, GOOF = 1.047, Z = 2, the final R1 = 0.0739 and wR2 = 0.2041 for I > 2σ(I). Crystal structural analysis reveals that complex I possesses the corrugated 1D chain structure extending along the \([\bar 101]\) direction. However, complex II displays a 2D coordination network lying on the ab crystal plane, which can be simplified as a binodal 3-connected 63 topological network by considering Cd2+ ions and L3 ligands as 3-connected nodes. Their photoluminescent and thermal properties were also investigated.  相似文献   

20.
From the solution of the system Na2WO4-HNO3-Ni(NO3)2-H2O acidified to Z = ν(H+)/ν(WO 4 2? ) = 1.29, the green crystals of nickel paratungstate B Ni5[W12O40(OH)2]·37H2O are isolated. By FTIR spectroscopy the isopoly anion is shown to belong to the structural type of paratungstate B. Using single crystal X-ray analysis, the structure of Ni5[W12O40(OH)2]·37H2O is solved (M r = 3840.36, monoclinic, P21/c space group, a = 21.9061(6) Å, b = 14.9297(4) Å, c = 22.1391(6) Å, β = 107.609(3)°, V = 6901.4(3)Å3 at T = 293 K, Z = 4, dx = 3.696 g/cm3, F 000 = 6944, μ = 21.368 mm?1, ?33 ≤ h ≤ 33, ?22 ≤ k ≤ 22, ?33 ≤ l ≤33; the final uncertainty values for the observed reflections are R F = 0.0532, wR 2 = 0.0831 (R F = 0.1088, wR 2 = 0.0894 over all independent reflections), S = 0.978; CSD-421468).  相似文献   

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