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1.
The structure and the EPR spectra of copper(II) coordination compounds with acyldihydrazones of N-benzenesulfonyl-L-aspartic acid and salicylaldehyde (2-hydroxyacetophenone) were described. The compounds were studied by chemical and thermal analyses, IR spectroscopy, and EPR. The molecular and crystal structures of copper(II) complexes with N-benzenesulfonyl-L-aspartic acid bis(salicylidene)hydrazone (H4L1) [Cu2L1 · 2Py] · 1.5 H2O was determined by X-ray diffraction. The crystals are triclinic: a = 10.4714(4) Å, b = 12.9702(5) Å, c = 14.6187(9) Å, α = 104.763(2)°, β = 93.082(2)°, γ = 111.4240(10)°, space group P \(\bar 1\), Z = 2. The binuclear complexes containing copper cations whose coordination polyhedra are connected by an aliphatic spacer (Cu...Cu, 8.669 Å) are additionally linked by phenoxy bridges (Cu...Cu, 3.398 Å). The EPR spectra of these compounds in solutions exhibit an isotropic signal of seven HFS lines due to two equivalent copper ions with the spin Hamiltonian parameters g = 2.115?2.120, a Cu = (35.5?38.0) × 10?4 cm?1, which is indicative of weak exchange interactions between the paramagnetic sites.  相似文献   

2.
Binuclear copper(II) complexes with acyldihydrazones of 1,3- or 1,4 benzenedicarboxylic acid and 5-methyl- or 5-bromo-2-hydroxyacetophenone in which coordination polyhedra are connected by an aromatic bridge have been synthesized and studied. The structure of the copper(II) complex with diacylhydrazone of isophthalic acid and 2-hydroxy-5-methylacetophenone (H4L) of composition [Cu2L · 3Py] was studied by X-ray diffraction. The crystals are monoclinic: a = 12.1996(12) Å, b = 17.7295(17) Å, c = 17.9339(17) Å, β = 109.7450(10)°, space group P21/n, Z = 4. The complex is of the “dimer of dimers” type and contains two binuclear subunits that bind together into a centrosymmetric dimer owing to the coordination of the copper cation to the phenoxyl oxygen atom of a neighboring binuclear molecule to form the Cu2O2 moiety, in which the copper atoms are 3.409 Å apart. The distance between the copper(II) cations in the binuclear subunit is 8.56 atoms (2N + O) of the doubly deprotonated acylhydrazone moiety and the nitrogen atom of the pyridine molecule. One of the copper cation is additionally coordinated to an extra pyridine molecule so that its coordination sphere is completed to a tetragonal pyramid. The second copper atom is involved in additional interaction with the phenoxyl oxygen atom of the neighboring molecule. The EPR spectra of solutions of the binuclear complexes show an isotropic signal of four HFS lines (g o = 2.065–2.143, a Cu = 52.1–66.5 × 10?4 cm?1) typical of mononuclear copper(II) complexes.  相似文献   

3.
The structure and EPR spectra of copper(II) complexes with bis(salicylidene)hydrozones of N-benzoyl-L-aspartic and N-benzoyl-L-glutamic acids have been described. The compounds have been studied by chemical and thermal analyses, IR spectroscopy, and EPR spectroscopy. The molecular and crystal structure of the copper(II) complex with bis(salicylidene)hydrozone of N-benzoyl-L-aspartic acid (H4L) of composition [Cu2L · 2Py] · 2CH3OH · H2O has been determined by X-ray single-crystal diffraction. The crystals are monoclinic: a = 10.3316(7) Å, b = 16.7552(9) Å,c = 11.0137(6) Å, β = 105.758(3)°, space group P21, Z = 2. The complex has a polymeric structure composed of alternating copper-containing binuclear fragments bound to each other either via phenoxy bridges or via an aliphatic spacer (the Cu…Cu distances are 3.471 Å and 8.939 Å, respectively). The EPR spectra of the solutions of the complexes under study shows an isotropic signal comprising seven HFS lines due to two equivalent copper nuclei with the spin Hamiltonian parameters g = 2.115–2.122 and a Cu = (36.1–36.9) × 10?4 cm?1, which indicates the reaization of weak exchange coupling of the paramagnetic centers.  相似文献   

4.
Binuclear copper(II) complexes with acyldihydrazones of benzenedicarboxylic acid and trifluoroacetylacetone have been synthesized and studied. The structure of the copper(II) complex with diacylhydrazone of 1,3-benzenedicarboxylic acid (H4L) of composition [Cu2L · 2LPy] has been studied by X-ray diffraction. The crystals are triclinic: a = 9.2298(4) Å, b = 11.8510(6) Å, c = 13.8314(7) Å, α = 90.780(3)°, β = 96.124(3)°, γ = 99.264(3)°, space group \(P\bar 1\), Z = 2. The number of symmetry-unrelated reflections with I > 2σ(I) 5941; R = 0.0357, R w = 0.0589. The complex contains two equivalent copper atoms at a distance of 9.56 Å from each other in the square-planar coordination environment. The high-temperature EPR spectra of the complexes show a signal of seven HFS lines indicating the coupling of unpaired electrons to two equivalent copper nuclei (g = 2.113?2.116, a Cu = 37.0?37.2 × 10?4 cm?1).  相似文献   

5.
A copper(II) complex with salicylaldehyde N-(2-salicylideneiminoglutaryl)hydrazone (H4L) of the formula [Cu2L · 2Py]2 · 8H2O (I) was obtained and characterized by X-ray diffraction. The crystals are monoclinic, space group P21, a = 13.0663 Å, b = 16.5553 Å, c = 17.7650 Å, β = 97.9420°; Z = 4. The complex is tetranuclear with a “dimer-of-dimers” structure in which the copper cations of two binuclear subunits are linked by phenoxy bridges. The EPR spectra of solutions of complex I show a superposition of two signals of four HFS lines (g 1 = 2.111, a 1 = 56.8 × 10?4 cm?1 and g 2 = 2.183, a 2 = 71.0 × 10?4 cm?1).  相似文献   

6.
The structure of the hexanuclear copper(II) β-diketonate complex with gfa (hexafluoroacetylacetone) and dpm (dipivalylmethanate) ligands was studied by low-temperature (T = 100 K) X-ray diffraction. Crystal data for Cu6(gfa)4(dpm)4(OH)4 [C64H84Cu6F24O20]: a = 28.2364(7) Å, b = 12.8072(3) Å, c = 24.7199(7) Å, β= 115.900(1)°, V = 8041.5(4) Å3, space group C2/m, Z = 4, d calc 1.661 g/cm3. The coordination polyhedra of the copper atoms — squares and octahedra — are formed by the oxygen atoms of the gfa and dpm ligands and groups. In all cases, the Cu-O distances vary from 1.89 Å to 2.13 Å. The complexes follow the sites of the rhombohedral sublattice with the parameters a c ≈ 14.4 Å and a c ≈ 61.5°.  相似文献   

7.
Ammonium decamolybdodimetallates (NH4)n[M2Mo10O34(OH)4] · 7H2O, where M = Cr3+ (n = 6), Cu2+ (n = 8), or Ni2+ (n = 8), were synthesized for the first time and studied by X-ray diffraction, thermogravimetry, and IR spectroscopy. The compounds crystallize in the triclinic system with the following unit cell parameters: a = 10.68(2) Å, b = 9.46(2) Å, c = 7.97(2) Å, α = 75.12(3)°, β = 96.82(3)°, γ = 102.21(3)°, V = 754.4(3) Å3, ρcalcd = 4.05 g/cm3, Z = 1 for the chromium compound; and a = 10.57(2) Å, b = 9.29(2) Å, c = 8.47(2) Å, α = 73.91(3)°, β = 96.05(3)°, γ = 104.71(3)°, V = 854.3(3) Å3, ρcalcd = 3.68 g/cm3, Z = 1 (for the copper compound); and a = 10.96(2) Å, b = 8.95(2) Å, c = 7.40(2) Å, α = 71.76(3)°, β = 97.04(3)°, γ = 102.91(3)°, V = 875.3(3)Å3, ρcalcd = 3.65 g/cm3, Z = 1 for the nickel compound.  相似文献   

8.
The adducts of binuclear copper(II) complexes with acyldihydrazones formed by 1,3- or 1,4-benzenedicarboxylic acid and some nitrogen-containing Lewis bases (pyrrolidine, piperidine) were synthesized and studied. The structure of copper(II) complex with bis(salicylidene)hydrazone of terephthalic acid (H4L), [Cu2L(Pirr)4] · CH3OH, was determined by X-ray diffraction data. The crystals are monoclinic: a = 15.5142(7) Å, b = 13.8784(6) Å, c = 17.8873(8) Å; β = 91.990(2)°, space group C2/c, Z = 4. The number of symmetrically independent reflections was 4269, R = 0.0303, R w = 0.0827. The complex contains two equivalent copper atoms located at a 11.021 Å is a tetragonal pyramid. EPR spectral features of the adducts were studied.  相似文献   

9.
A trinuclear copper(II) complex of trimesic acid salicylidene hydrazone (H6L) having the composition [Cu3L · 4Py] · CH3OH was synthesized and characterized. By X-ray crystallography, the crystals are triclinic: a = 11.7940(4) Å, b = 13.7241(5) Å, c = 15.8993(6) Å, α = 107.4120(10)°, β = 94.2900(10)°, γ = 105.5650(10)°, space group \(P\bar 1\), Z = 2. The number of symmetrically unique reflections having I > 2σ(I) is 7636, R = 0.0465, and R w = 0.1198. The newly prepared complex contains, in its unit cell, two [Cu3L · 4Py] molecules which are linked to form a dimer on account of phenoxo bridges (the Cu-O bond length is 2.555 the Cu…Cu distance is 3.348 Separations between them are 9.414, 9.371, and 9.667 of temperature is satisfactorily fitted in terms of a triangular cluster model (?2J = 2.2 cm?1) with extra intermolecular interactions (zJ′ = 0.4 cm?1). EPR spectra of solutions at 360–380 K feature a poorly resolved HFS, whose modeling gives a satisfactory result with allowance for the interaction of unpaired electrons with three equivalent copper nuclei (g = 2.098; a Cu = 25.8 × 10?4 cm?1).  相似文献   

10.
A novel Cu(II) complex Cu2(Endc)2(Bipy)2 has been synthesized by the reaction of Cu(NO3)2 · 3H2O, Endc (endo-norbornene-cis-5,6-dicarboxylic acid), and Bipy (2,2-bipyridine) at room temperature. Elemental analysis, IR spectra, and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure. Crystal data for this complex: triclinic, P \(\bar 1\) with a = 9.0373(10), b = 10.1637(11), c = 10.5574(12) Å, α = 65.78(1)°, β = 72.32(2)°, β = 73.23(2)°, Z = 1, V = 827.46(16) Å3, ρ c = 2.160 g/cm3, F(000) = 410.0, R = 0.0483 and wR = 0.0958 independent reflections for 4468 observed ones (I > 2 σ(I)).The Cu2+ ion is coordinated by two nitrogen atoms from the Bipy molecule and three oxygen atoms from two Endc, giving a distorted squarepyramidal coordination geometry. Two neighboring Cu2+ ions are bridged by a pair of bimonodentate carboxyl groups of different Endc acids, giving a centrosymmetrical binuclear structure which a Cu…Cu distance of 3.2946 Å. The photoluminescence properties of the complex were studied at room temperature. The complex displays an obvious photoluminescent emission upon excitation at 390 nm in the solid state.  相似文献   

11.
Copper(II) binuclear complexes with acyldihydrazones of saturated carboxylic acids and pyruvic acid in which the coordination polyhedra are connected by polymethylene chains of different length (1 to 5 units) were synthesized and studied by chemical and thermogravimetric analysis, IR spectroscopy, and EPR. The structure of binuclear copper(II) complex with succinic acid acyldihydrazone [Cu2L · 4Py] · 2Py was determined by X-ray diffraction. The crystals are monoclinic: a = 14.3795(6), b = 8.8736(4), c = 15.9147(7) Å, β = 101.062(3)°, space group P21/c, Z = 2. The number of independent reflections with I > 2σ(I) = 2804, R = 0.042, R w = 0.087. The copper atoms are spaced by a chain of seven σ bonds at 8.922 Å. The coordination polyhedron can be described as a tetragonal pyramid highly distorted toward a trigonal bipyramid. The EPR spectra of solutions of complexes based on malonic, succinic, glutaric, and adipinic acids exhibit a poorly resolved signal of seven HFS lines with a constant of (26.3–27.0) × 10?4 cm?1, which attests to the presence of weak exchange interactions between paramagnetic centers. An increase in the length of the polymethylene spaur suppresses exchange interactions, and the EPR spectrum of the complex based on pimelic acid acyldihydrazone shows a signal of four HFS lines with a constant of 43.8 × 10?4 cm?1 typical of monomeric copper(II) complexes.  相似文献   

12.
Tri-p-tolylbismuth perchlorate (1) and μ-oxo-bis[(perchlorato)tri-p-tolylbismuth] (2) have been synthesized by the reaction between tri-p-tolylbismuth dibromide and silver perchlorate and its hydrate. The complexes have been studied by chemical analysis, IR spectroscopy, and X-ray diffraction. Complex 1 is triclinic, space group Pī, Z = 4, a =10.7271(9) Å, b = 13.5585(11) Å, c = 18.1592(13) Å, α = 110.867(3)°, β = 94.944(3)°, γ = 96.888(3)°, V = 2426.3(3) Å3, ρcalcd = 1.865 g/cm3; complex 2 crystallizes in trigonal symmetry, space group R\(\bar 3\), a = 13.1157(2) Å, c = 22.1959(2) Å, γ = 120°, V = 3306.64(8) Å3, ρcalcd = 1.777 g/cm3. The bismuth atoms in the molecular structure of complex 1 have a distorted trigonal bipyramidal coordination to the apically arranged oxygen atoms of perchlorate ions (Bi–C, 2.180(5)–2.201(5) Å; Bi–O, 2.324(4)–2.355(4) Å; OBiO axial angles, 170.1(1)°, 174.5(1)°). The structure of complex 2 contains binuclear [p-Tol3Bi(ClO4)]2O molecules (Bi–O, 2.371(15), 1.9107(7) Å; OBiO axial angle, 180.0°).  相似文献   

13.
The crystal structure of (hexafluoroacetylacetonato)(pivaloylacetonato)copper(II) has been determined. Crystal data for CuO4C13H14F6: a = 8.288(2) Å, b = 8.682(2) Å, c = 12.307(2) Å; α = 90.75(3)°, β = 94.29(3)°, γ = 106.60(3)°; V = 845.7(3) Å3, space group \(P\overline 1 \), Z = 2, dcalc = 1.617 g/cm3. The coordination polyhedron of the copper atom is formed by four oxygen atoms of two different β-diketonate ligands with Cu-O distances within 1.874–1.946 Å; the O-Cu-O bond angles are 94.8° and 90.6°. The complexes are united into centrosymmetrical “dimers” with Cu...Cu distances of 4.365 Å.  相似文献   

14.
The title compound (disodium dipotassium copper(II) tris-[molybdate (VI)]) is prepared by form melt and characterized by single crystal X-ray diffraction and UV-vis spectroscopy. It crystallizes in the triclinic space group P-1 with a = 7.4946(8) Å, b = 9.3428(9) Å, c = 9.3619(9) Å, α = 92.591(7)°, β = 105.247(9)°, γ = 105.496(9)°, V = 604.7 Å3, and Z = 2. Its structure is isotypic with that of Na4Mn(MoO4)3. It is formed by Cu2O10 distorted bi-octahedral dimers linked by two bridging bidentate Mo2O4 tetrahedra and, additionally, two monodentate Mo1O4 tetrahedra to form Cu2Mo4O20 units. These units are linked by the insertion of Mo3O4 tetrahedra to build infinite ribbons disposed along the c axis. All of these ribbons form a one-dimensional framework. Both K1 and K3 cations are located in the inversion center, and all the other atoms are at general positions. The structure model is supported by the bond valence sum (BVS) and charge distribution CHARDI methods. The Cu2+ cations adopt the [4+2] CuO6 Jahn-Teller distortion giving rise to an intense dd transition in the UV-vis absorption spectra.  相似文献   

15.
trans-Bis-(4-phenyliminopentan-2-onato)Cu(II) (5), which is a phenyl-substituted ketoimine, was synthesized, and an X-ray study was performed for this compound. Crystal data for CuN2O2C22H24: a = 11.4557(3) Å, b = 26.6845(9) Å, c = 14.2976(5) Å, β = 113.2270(10)°; space group P21/n, Z = 8, d calc = 1.363 g/cm3, R = 0.033. The structure is molecular and built of isolated trans complexes. The central copper atom is surrounded by four atoms (2O+2N) with the average distances Cu-O 1.904(3) Å and Cu-N 1.962(3) Å. The polyhedron around the copper atom is a distorted tetrahedron; the average values of the O-Cu-O and N-Cu-N trans bond angles are 147(2)° and 150(2)°, respectively. The average value of the O-Cu-N angles is 94(1)°.  相似文献   

16.
A novel copper(II) complex {[Cu(BIX)2(H2O)2](PhCOO)2} n (1) (BIX = 1,4-bis(imidazole-1-methyl))-benzene) is synthesized and characterized by elemental analysis, IR, TG, and single crystal X-ray diffraction. Complex 1 crystallizes in the triclinic crystal system with the P-1 space group, Z = 1, a = 9.465(2) Å, b = 9.703(2) Å, c = 12.060(2) Å, α = 77.26(3)°, β = 70.37(3)°, γ = 67.14(3)°, and V = 956.1(3) Å3. The crystal structural analysis of complex 1 shows that the copper center is six-coordinated in an elongated octahedral geometry by four N atoms from four different BIX and two O atoms from two water molecules; two neighboring Cu(II) cations are bridged by two BIX extending into an infinite 1D double chain structure.  相似文献   

17.
The structure of two stereoisomeric spiroadducts of allobetulone with 5-phenyl-2,3-dihydrofuran-2,3-dione was established by X-ray diffraction (XRD) analysis. The crystals of the 2R isomer are orthorhombic, P212121, a = 10.825(5) Å, b = 12.849(6) Å, c = 23.358(9) Å; V = 3249(2) Å3, Z = 4, d calc = 1.200 g/cm3; the crystals of the 2S isomer hemihydrate are triclinic, P1, a = 11.505(7) Å, b = 12.192(8) Å, c = 13.123(8) Å; α = 103.35(5)°, β = 100.80(5)°, γ = 90.98(5)°; V = 1756(2) Å3, Z = 2, d calc = 1.127 g/cm3. The molecular structure of the spiroadducts is discussed.  相似文献   

18.
The crystal structures of catechol (o-dihydroxybenzene) and its 2:1 complex with dimethylsulfoxide are determined at T = 150 K. Crystal data: C14H18O5S, M = 298.37, triclinic, space group P \(\bar 1\), unit cell parameters: a = 7.7285(13) Å, b = 9.9924(17) Å, c = 10.3188(18) Å, α = 89.963(4)°, β = 89.968(4)°, γ = 69.076(5)°, V = 744.3(2)Å3, Z = 2, D x = 1.331 g/cm3, R1 = 0.048; C6H6O2, M = 110.11, monoclinic, space group P21/n, a = 9.8206(6)Å, b = 5.5903(3)Å, c = 10.4439(6)Å, β = 114.952(2)°; V = 519.85(5) Å3, Z = 4, D x = 1.407 g/cm3, R1 = 0.0289. In the 2:1 complex the molecules are joined in a supramolecular ensemble by D-H...A hydrogen bonds (D = O, C; A = O, π); in catechol they are bonded only by O-H...O. The state diagram of the catechol-dimethylsulfoxide system is examined by DTA.  相似文献   

19.
The crystal structure of dichlorobis(dimethylsulfoxide-O)copper(II), [CuCl2(DMSO)2] (I), previously determined by Willett and Chang, is reinvestigated. It crystallizes in the orthorhombic system with the space group Pnma (N°62), Z = 4, and unit cell parameters a = 8.053(1) Å, b = 11.642(5) Å, c = 11.347(3) Å. Our structure determination is of a significantly higher precision in terms of bond lengths, angles, and R factors (e.g., Cu1–O1 = 1.9737(24) Å, O1–Cu1–O1i = 173.08(13)° (symmetry code: I x, 1/2–y, z) and R(F 2) = 0.046 compared to 1.955(4) Å, 173.0(3)° and R(F) = 0.075). In contrast to the previous investigation, all H atoms are placed at calculated positions. In the title molecule, the CuII atom is five coordinated in a distorted square pyramidal geometry. Thus, as reported previously, it can be shown that the crystal structure consists of [CuCl2(DMSO)2] molecules which, by virtue of long Cu–Cl interactions, are tied together to form chains parallel to the [100] direction. The density functional theory (DFT) optimized structure at the B3LYP/6-311++G(2d,2p) level is compared with the experimentally determined molecular structure. The HOMO-LUMO energy gap and other related molecular properties are also calculated. Comprehensive experimental and theoretical structural studies on the studied complex are carried out by FT-IR and UV-visible spectroscopies.  相似文献   

20.
The reaction of copper(II) cysteinate with thiosemicarbazide (TSC) in water was found to yield complex of copper(II) thiocyanate of the [Cu(TSC)2(SCN)2] composition, whose crystal structure was determined by X-ray crystallography. Crystals of the complex are triclinic with a = 6.040 Å, b = 7.112 Å, c = 8.276 Å, α = 91.34°, β = 101.72°, Γ = 114.83°, Z = 2, space group \(P\bar 1\). Structural units of the complex are [Cu(TSC)2]2+ centrosymmetric cations and (SCN)? anions linked by hydrogen bonds (HB), as well as by electrostatic and π-π stacking interactions. The coordination polyhedron of Cu atoms is a square completed to bipyramid; the bonds Cu(1)-N(3), Cu(1)-S(1), and Cu(1)-S(2) are 2.002 Å, 2.303 Å, and 3.015 Å, respectively.  相似文献   

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