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1.
The compound phenol,2-[4(S)-4,5-dihydro-4-phenyl-2-ozazolinyl(1,C15H13NO2) was synthesized with a simple,one step method free of water and air.It was obtained in a moderate yield from the reaction of 2-hydroxybenzonitrile with optically active amino alcohol in chloroben-zene under dry,anaerobic conditions.It belongs to the orthorhombic system,space group P212121 with a = 5.786(5),b = 10.730(5),c = 19.722(5),C15H13NO2,Mr = 239.26,V = 1224.4(12)3,Z = 4 and Dc = 1.298 mg/m3.The final R = 0.0324 for 1627 observed reflections with Ⅰ 2σ(Ⅰ) and Rw = 0.0826 for all data.The structure of compound 1 was determined by X-ray diffraction,NMR and HRMS.  相似文献   

2.
The title compound 2-(5-(4-chlorophenyl)-1-phenyl-4,5-dihydro-1H-pyrazol-3-yl)- pyridine(C20H16ClN3, Mr = 333.81) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a = 10.9925(12), b = 11.0378(12), c = 14.2751(18) , β = 98.074(11)°, V = 1714.9(3)3, Z = 4, Dc = 1.293 g/cm3, μ(MoKα) = 0.228 mm-1, F(000) = 696, the final R = 0.0521 and wR = 0.1349 for 3495 observed reflections with I 2σ(I). Intermolecular C–H...π interactions and π-π stacking interactions stabilize the crystal structure. The binding study by fluorescence spectroscope titration showed that the title compound can selectively recognize Fe3+ in THF solution with fluorescence quenching.  相似文献   

3.
N-[2-(4-chlorophenyl)-1-(1-methylcarbamoyl-2-phenyl-ethylcarbamoyl)-3-phenyl-cyclopropyl]benzamide,C33H30ClN3O3,has been synthesized and characterized by IR,1H NMR,13C NMR and single-crystal X-ray diffraction.The crystal is of triclinic,space group P1 with a = 11.646(2),b = 13.795(3),c = 14.559(3),α = 76.422(4),β = 78.028(4),γ = 74.500(4)°,V = 2164.6(7)3,Z = 3,Mr = 552.05,Dc = 1.270 g/cm3,λ = 0.71073 ,μ(MoKα)= 0.171 mm–1,F(000)= 870,the final R = 0.0469 and wR = 0.0805 for 5554 observed reflections with I > 2σ(I).The N–H and oxygen atoms are involved in one-dimensional intermolecular hydrogen bonds,which further stabilize the structure.  相似文献   

4.
孙海燕 《结构化学》2014,33(10):1467-1471
The novel crystal of the title compound 2-(((5-(((5,7-dimethyl-[1,2,4]triazolo-[1, 5-a]-pyrimidin-2-yl)thio)methyl)-4-phenyl-4H-1,2,4-triazol-3-yl)thio)methyl)-4H-chromen-4-one methanol solvate(C27H25N7O3S2, Mr = 559.66) has been prepared and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to the monocline system, space group P21/c with a = 11.9879(9), b = 14.0743(10), c = 15.9706(11), β = 98.509(2)°, V = 2664.9(3)3, Z = 4, Dc = 1.395 g/cm3, F(000) = 1168, μ = 0.116 mm-1, MoKa radiation(λ = 0.71073), R = 0.0652, and wR = 0.1425 for 5220 observed reflections with I 2σ(I). X-ray diffraction analyses reveal that the molecule adopts a C-shape. The planes of the benzopyrone and triazolopyrimidine were nearly parallel to each other, with a dihedral angle of 1.21(3)°. Intramolecular and intermolecular hydrogen bonds together with π-π interations are found to exist in the structure. The results of MTT assay indicate that the title compound displays excellent antiproliferative activity against two human cancer cell lines.  相似文献   

5.
HU  Ai-Xi QIN  Zhi YE  Jiao XIA  Shu 《结构化学》2010,29(11):1680-1683
The title compound (E)-4-tert-butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine was synthesized by the reaction of 4-tert-butyl-5-(1,2,4-triazol-1-yl)-thiazol-2-amine with 2,4-dichlorobenzaldehyde, and its crystal structure was determined by singlecrystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 7.9748(4), b = 10.1803(5), c = 11.4603(6), α = 102.882(1), β = 100.253(1), γ = 104.457(1)°, V = 850.95(7)3, Z = 2, F(000) = 392, C16H15Cl2N5S, Mr = 380.29, Dc = 1.484 g/cm3, S = 1.095, μ = 0.512 mm-1, the final R = 0.0301 and wR = 0.0965 for 3334 observed reflections (I 2σ(I)). The preliminary antitumor activity shows that for the title compound the IC50 of Hela is 0.175 μmol/mL and that of Bel7402 is 0.156 μmol/mL.  相似文献   

6.
方庭  步洪飞  薛思佳  刘丽  丁丽  王晶 《结构化学》2011,30(10):1452-1458
A novel neonicotinoid analogue(C13H19N5O5,3a)had been synthesized,the structure was characterized by elemental analysis,IR and 1H NMR spectra,and the S-(+)-(E)-configuration was confirmed by single-crystal X-ray diffraction.The crystal belongs to monoclinic,space group P21 with a = 8.7076(17),b = 8.3211(17),c = 10.642(2),β = 92.370(3)o,V = 770.4(3)3,Z = 2,Dc = 1.402 g/cm3,μ = 0.110 mm-1,Mr = 325.33,F(000)= 344,S = 1.027,R = 0.0543 and wR = 0.1229 for 3601 unique reflections with 2919 observed ones(I > 2σ(I)).Compound 3a is stabilized by intramolecular hydrogen bonds and intermolecular force.In addition,the structure of compound 3a was optimized by the B3LYP/6-31G(d,p).DFT/B3LYP optimizations were performed based on X-ray geometries applying 6-31G(d,p)basis set.The optimized structure of compound 3a by the B3LYP/6-31G(d,p)method is more bent than in the crystal.IR spectrum of the solid compound is consistent with the X-ray structure.The HOMO-LUMO gap in 3a(5.3 eV)indicates high kinetic stabilities of compound 3a.The preliminary bioassay test showed that 3a exhibited good activities against Nilaparvata legen,Pseudaletia separate Walker and Aphis medicagini at 500 mg/L.  相似文献   

7.
The title compound of Cu(C14H9O3)2(C5H5N)2(C2H5OH)2(1) was synthesized via the hy- drothermal reaction of CuCl2·2H2O and 9-hydroxy-fluorene-9-carboxylic acid(HHF) with pyridine, and characterized by elemental analysis and infrared spectra. The crystal belongs to triclinic, space group P1 with a = 8.8302(12), b = 10.1625(14), c = 12.2708(17), α = 86.207(2), β = 69.562(2), γ = 64.932(2)o, V = 930.3(2) 3, Z = 1, Mr = 764.30, Dc = 1.364 g/cm3, F(000) = 399, S = 1.059 and μ(MoKα) = 0.644 mm-1. The final R = 0.0459 and wR = 0.1274 for 3414 observed reflections with I 2σ(I). The copper atom is six-coordinated by two oxygen atoms from two different 9-hydroxy-fluorene-9-carboxylate ligands, two pyridine nitrogen atoms and two ethanol oxygen atoms, forming a distorted octahedral coordination geometry. The extensive O–H···O hydrogen bonding connects the molecules to form a one-dimensional chain structure. Between adjacent one-dimensional chains, a two-dimensional layered structure was formed by fluorene ring π-π packing interaction. Between the layers, a three-dimensional structure was formed through the π-π packing interaction of the pyridine ring. Moreover, the thermal stability and photoluminescent property of the complex has been investigated.  相似文献   

8.
The title compounds,C9H13ClN6O2S 1 and C15H17ClN6O2S 2,were synthesized and structurally characterized by elemental analysis,IR,1H NMR spectra and single-crystal X-ray diffraction.Compound 1 is in the monoclinic system,space group P21/c with a=13.7711(5),b=10.3883(4),c=9.7623(2),V=1344.47(8)3,Dc=1.506 g/cm3,C9H13ClN6O2S,Mr=304.76,F(000)=632,μ=0.448 mm-1,Z=4,S=1.084,R=0.0497 and wR=0.1328 for 2640 unique reflections(Rint=0.0787) with 2089 observed ones(I2σ(I)).Compound 2 belongs to the monoclinic system,space group P21/n with a=8.3828(5),b=14.5285(7),c=14.2456(4),V=1729.74(14)3,Dc=1.462 g/cm3,C15H17ClN6O2S,Mr=380.86,F(000)=792,μ=0.364 mm-1,Z=4,S=1.057,R=0.0598 and wR=0.1582 for 3384 unique reflections(Rint=0.0469) with 2833 observed ones(I2σ(I)).Compounds 1 and 2 are homologues and stabilized by intermolecular and intramolecular hydrogen bonds.Moreover,compound 2 containing C(2)-H(2)…π(thiazole) interaction is more stable than 1.  相似文献   

9.
苏清  赵天琦  张杰  李佩  赵晴  叶玲 《结构化学》2014,(2):237-243
6,8-Di-tert-butyl-3-(2,4-dimethyl-quinolin-7-yl)-3,4-dihydro-2H-benzo[e][1,3]oxa- zine(1) was obtained by one-pot reaction starting from 2,4-di-tert-butylphenol, 7-amino-2,4- dimethyl-quinoline and paraformaldehyde. The compound was structurally characterized by NMR, IR and single-crystal X-ray diffraction along with the elemental analysis. Compound 1 crystallizes as solvate with chloroform. The solvate 1·CHCl3(C28 H35 Cl3 N2 O, Mr = 521.93) belongs to the triclinic system, space group P1 with a = 10.852(2), b = 11.352(2), c = 13.050(3), α = 101.95(3), β = 92.94(3), γ = 114.64(3)o, V = 1412.4(5)3, Z = 2, Dc = 1.227 g/cm3, F(000) = 552, μ = 0.347 mm–1, R = 0.0959 and wR = 0.2725(I 2?(I)). The chloroform molecule displays a rotational disorder as one chloro atom can be located at two different positions. The packing of 1·CHCl3 was further stabilized by intramolecular C–H···O interactions, intermolecular C–H···N interactions, C–H···π interactions, and π···π interactions. The luminescent properties of compound 1 in both methylene chloride solution and the solid state were studied.  相似文献   

10.
The title compound N 1-(1,3,4-thiadiazole-2-yl)-N 3-m-chlorobenzoyl-urea (C 9 H 7 N 4 OSCl,M r=254.70) was prepared by the reaction of m-chlorophenyl isocyanate with 2-amino-1,3,4-thiadiazole in dry acetonitrile.The effect of the title compound on tumor metastasis was analyzed by Lewis-lung-carcinoma model.The bioassay showed that the title compound significantly reduced the number of lung metastasis.The crystal structure has been determined by X-ray diffraction.The crystal belongs to the monoclinic system,space group P2 1 /c with a=11.565(2),b=9.5616(19),c=10.221(2),β=111.75(3)°,Z=4,V=1049.8(4)3,D c=1.612 Mg/m 3,F(000)=520,μ(MoKa)=0.544 mm-1,R=0.0468 and wR=0.0922 for 1236 observed reflections (I > 2σ(I)).  相似文献   

11.
The title compounds have been respectively synthesized by solution process and solvothermal reaction, and their crystal structures were determined by X-ray diffraction method. For (CH3CH2CH2CH2NH3)6(BiI6)(I)2I3 1, it crystallizes in tficlinic, space group P1^- with Mr = 2049.76, a = 8.5719(1), b = 11.7461(3), c = 15.700(1)A, V = 1451.4(1)A^3, Z = 1, Dc = 2.345 g/cm^3, F(000) = 924, μ(MoKα) = 8.907 mm^-1, T = 293(2) K, the final R = 0.0655 and wR = 0.0804 for 2399 observed reflections with I 〉 2σ(I). For (NH3CH2CH2NH3)2Bi2I10 2, it crystallizes in monoclinic, space group P21/n with Mr= 1811.20, a = 8.434(4), b = 13.862(6), c = 13.362(6)A, V = 1499.9(12)A^3, Z = 2, Dc = 4.010 g/cm^3, F(000) = 1536,μ(MoKα) = 22.007 mm^-1, T = 293(2) K, the final R = 0.0584 and wR = 0.1451 for 1798 observed reflections with I 〉 2σ(I). The structures of 1 and 2 contain halobismuthate monomer and dimers, respectively. It is noteworthy that the dimers and their organic counters in 2 connect each other by N…I hydrogen bonds to form a layered structure, and the electrostatic interactions and crystal packing forces between layers give rise to the packing of the crystal. The optical absorption spectra of 1 and 2 reveal the appearance of sharp optical gaps of 2.13 and 2.01 eV, respectively.  相似文献   

12.
CoSm(SeO3)2Cl, CuGd(SeO3)2Cl, MnSm(SeO3)2Cl, CuGd2(SeO3)4 and CuSm2(SeO3)4: Transition Metal containing Selenites of Samarium and Gadolinum The reaction of CoCl2, Sm2O3, and SeO2 in evacuated silica ampoules lead to blue single crystals of CoSm(SeO3)2Cl (triclinic, , Z = 4, a = 712.3(1), b = 889.5(2), c = 1216.2(2) pm, α = 72.25(1)°, β = 71.27(1)°, γ = 72.08(1)°, Rall = 0.0586). If MnCl2 is used in the reaction light pink single crystals of MnSm(SeO3)2Cl (triclinic, , Z = 2, a = 700.8(2), b = 724.1(2), c = 803.4(2) pm, α = 86.90(3)°, β = 71.57(3)°, γ = 64.33(3)°, Rall = 0.0875) are obtained. Green single crystals of CuGd2(SeO3)2Cl (triclinic, , Z = 4, a = 704.3(4), b = 909.6(4), c = 1201.0(7) pm, α = 70.84(4)°, β = 73.01(4)°, γ = 70.69(4)°, Rall = 0.0450) form analogously in the reaction of CuCl2 and Gd2O3 with SeO2. CoSm(SeO3)2Cl contains [CoO4Cl2] octahedra, which are connected via one edge and one vertex to infinite chains. The Mn2+ ions in MnSm(SeO3)2Cl are also octahedrally coordinated by four oxygen and two chlorine ligands. The linkage of the polyhedra to chains occurs exclusively via edges. Both, the cobalt and the manganese compound show the Sm3+ ions in eight and ninefold coordination of oxygen atoms and chloride ions. In CuGd(SeO3)2Cl the Cu2+ ions are coordinated by three oxygen atoms and one Cl ion in a distorted square planar manner. One further Cl and one further oxygen ligand complete the [CuO3Cl] units yielding significantly elongated octahedra. The latter are again connected to chains via two common edges. For the Gd3+ ions coordination numbers of ?8 + 1”? and nine were found. Single crystals of the deep blue selenites CuM2(SeO3)4 (M = Sm/Gd, monoclinic, P21/c, a = 1050.4(3)/1051.0(2), b = 696.6(2)/693.5(1), c = 822.5(2)/818.5(2) pm, β = 110.48(2)°/110.53(2)°, Rall = 0.0341/0.0531) can be obtained from reactions of the oxides Sm2O3 and Gd2O3, respectively, with CuO and SeO2. The crystal structure contains square planar [CuO4] groups and irregular [MO9] polyhedra.  相似文献   

13.
The title compound,(E)-ethyl 2-(5-(3-methyl-2-butenyloxy)-2-(3-(4-(3-methyl-2-butenyloxy)phenyl) acryloyl) phenoxy)acetate(1),has been synthesized and characterized by FT-IR and 1H-NMR spectroscopy,ESI-MS,and X-ray single-crystal diffraction.FT-IR,1H-NMR and ESI-MS confirm the functional groups,particularly the ethyl groups in the ester moiety,of the compound.The single-crystal X-ray diffraction has revealed a monoclinic structure,space group P21/n with a = 14.6832(14),b = 7.7581(7),c = 23.075(2),β = 101.670(2)o,V = 2574.2(4) ?3,Z = 4,Dc = 1.235 g/cm,μ = 0.085 mm-1,and F(000) = 1024.The skeleton of chalcone in the molecular structure is coplanar.  相似文献   

14.
Five new vanadium selenites, Ca(2)(VO(2))(2)(SeO(3))(3)(H(2)O)(2), Sr(2)(VO(2))(2)(SeO(3))(3), Ba(V(2)O(5))(SeO(3)), Sr(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)), and Pb(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)), have been synthesized and characterized. Their crystal structures were determined by single crystal X-ray diffraction. The compounds exhibit one- or two-dimensional structures consisting of corner- and edge-shared VO(4), VO(5), VO(6), and SeO(3) polyhedra. Of the reported materials, A(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)) (A = Sr(2+) or Pb(2+)) are noncentrosymmetric (NCS) and polar. Powder second-harmonic generation (SHG) measurements revealed SHG efficiencies of approximately 130 and 150 × α-SiO(2) for Sr(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)) and Pb(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)), respectively. Piezoelectric charge constants of 43 and 53 pm/V, and pyroelectric coefficients of -27 and -42 μC/m(2)·K at 70 °C were obtained for Sr(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)) and Pb(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)), respectively. Frequency dependent polarization measurements confirmed that the materials are not ferroelectric, that is, the observed polarization cannot be reversed. In addition, the lone-pair on the Se(4+) cation may be considered as stereo-active consistent with calculations. For all of the reported materials, infrared, UV-vis, thermogravimetric, and differential thermal analysis measurements were performed. Crystal data: Ca(2)(VO(2))(2)(SeO(3))(3)(H(2)O)(2), orthorhombic, space group Pnma (No. 62), a = 7.827(4) ?, b = 16.764(5) ?, c = 9.679(5) ?, V = 1270.1(9) ?(3), and Z = 4; Sr(2)(VO(2))(2)(SeO(3))(3), monoclinic, space group P2(1)/c (No. 12), a = 14.739(13) ?, b = 9.788(8) ?, c = 8.440(7) ?, β = 96.881(11)°, V = 1208.8(18) ?(3), and Z = 4; Ba(V(2)O(5))(SeO(3)), orthorhombic, space group Pnma (No. 62), a = 13.9287(7) ?, b = 5.3787(3) ?, c = 8.9853(5) ?, V = 673.16(6) ?(3), and Z = 4; Sr(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)), orthorhombic, space group Fdd2 (No. 43), a = 25.161(3) ?, b = 12.1579(15) ?, c = 12.8592(16) ?, V = 3933.7(8) ?(3), and Z = 8; Pb(4)(VO(2))(2)(SeO(3))(4)(Se(2)O(5)), orthorhombic, space group Fdd2 (No. 43), a = 25.029(2) ?, b = 12.2147(10) ?, c = 13.0154(10) ?, V = 3979.1(6) ?(3), and Z = 8.  相似文献   

15.
Azido Complexes of Vanadium(IV) and Vanadium(V): (Ph4P)2[VOCl2(μ‐N3)]2 and (Ph4P)2[VOCl(μ‐N3)(N3)2]2 (Ph4P)2[VOCl2(μ‐N3)]2 ( 1 ) was prepared by reaction of (Ph4P)[VO2Cl2] with trimethylsilylazide in the molar ratio 1:2 in dichloromethane solution to give dark green, moisture sensitive, non‐explosive single crystals. The reaction is accompanied by the formation of the dark blue side‐product (Ph4P)2[VOCl(μ‐N3)(N3)2]2 ( 2a ), which can be obtained as the main product by application of a large excess of Me3SiN3. Dark blue needles of 2a crystallize spontaneously from the CH2Cl2 solution within one hour at 4 °C. After standing at 4 °C under its mother liquid within 24 hours a first‐order phase transition of 2a occurs forming dark blue prismatic single crystals of 2b . According to single crystal X‐ray structure determinations, 2a and 2b crystallize in the same type of space group , however, with different lattice dimensions. The vanadium(IV) complex 1 is characterized by X‐ray structure determination and by vibrational spectroscopy (IR, Raman) as well as by EPR spectroscopy, whereas 2b is characterized by IR spectroscopy. 1 : Space group P21/n, Z = 2, a = 1009.5(1), b = 1226.6(2), c = 1943.0(2) pm, β = 98.42(1)°, R1 = 0.0672. The complex anion forms centrosymmetric units with V2N2‐four‐membered rings with a V···V distance of 335.6(1) pm and coordination number five on the vanadium(IV) atoms. 2a : Space group , Z = 1, a = 1089.0(2), b = 1097.1(2), c = 1310.1(2) pm, α = 92.99(1)°, β = 106.12(2)°, γ = 117.05(2)°, V = 1309.8(4) Å3, dcalc. = 1.440 g·cm?3, R1 = 0.0384. The complex anion forms centrosymmetric units of symmetry Ci with V2N2 four‐membered rings and VN bond lengths of 200.4(3) and 234.4(2) pm, respectively. The non‐bonding V···V distance amounts to 356.2(1) pm. 2b : Space group , Z = 1, a = 1037.3(2), b = 1157.6(2), c = 1177.2(2) pm, α = 98.48(2)°, ° = 103.82(2)°, γ = 106.33(2)°, V = 1281.8(4) Å3, dcalc. = 1.471 g·cm?3, R1 = 0.0724. The structure of the complex anion is similar to the anion of 2a with VN bond lengths of the four‐membered V2N2 ring of 203.3(4) and 235.2(4) pm, respectively, and a non‐bonding V···V distance of 357.5(1) pm.  相似文献   

16.
This paper reports the optical properties of Dy(3+) in sodium fluoroborate glasses of the type XNaF.(89-X)B(2)O(3).10 Al(2)O(3).1Dy(2)O(3) (where X=8, 12, 16, 20 and 24). Judd-Ofelt intensity parameters (Omega(2), Omega(4), Omega(6)) are derived from the absorption spectra. The Judd-Ofelt theory has been applied to interpret the local environment of Dy(3+) ions and bond covalency of RE-O bond. These parameters have been used to calculate radiative transition probabilities (A(rad)), lifetimes (tau(R)) and branching ratios (beta(R)) for the excited level (4)F(9/2). The predicted values of tau(R) are compared with the measured values for (4)F(9/2) level for five glass compositions (Glass (A-E)). The stimulated emission cross-section sigma(lambda(P)) are also evaluated for the (4)F(9/2)-->(6)H(J) (J=11/2, 13/2, and 15/2) transitions.  相似文献   

17.
<正> M=1013.98, hexagonal, P63/m, a=b=15.492(2), c=8.530(4)A, γ=120°, V=1773A3, Z=2, Dc=1.899°g.cm-3. Final R=0.042 for 611 reflections.This is a Bl(bicapped) type trinuclear molybdenum cluster with two S capping atoms located on the 63 axis and exhibits full D3h symmetry. The Mo-Mo distances are 2.606(1)A, with a bond order of 11/3. It is paramagnetic.  相似文献   

18.
The synthesis, crystal structure, and magnetic properties of two trinuclear oxo-centered carboxylate complexes are reported and discussed: [Cr3(mu3-O)(mu2-PhCOO)6(H2O)3]NO3.4H2O.2CH3OH (1) and [Cr3(mu3-O)(mu2-PhCOO)2(mu2-OCH2CH3)2(bpy)2(NCS)3] (2). For both complexes the crystal system is monoclinic, with space group C2/c for 1 and P1/n for 2. The structure of complex 1 consists of discrete trinuclear cations, associated NO3- anions, and lattice methanol and water molecules. The structure of complex 2 is built only by neutral discrete trinuclear entities. The most important feature of 2 is the unusual skeleton of the [Cr3O] core due to the lack of peripheral bridging ligands along one side of the triangular core, which is unique among the structurally characterized (mu3-oxo)trichromium(III) complexes. Magnetic measurements were performed in the 2-300 K temperature range. For complex 1, in the high-temperature region (T > 8 K), experimental data could be satisfactorily reproduced by using an isotropic exchange model, H = -2J12S1S2 - 2J13S1S3 - 2J23S2S3 (J12 = J13 = J23) with Jij = -10.1 cm(-1), g = 1.97, and TIP = 550 x 10(-6) emu mol(-1). The antisymmetric exchange interaction plays an important role in the magnetic behavior of the system, so in order to fit the experimental magnetic data at low temperature, a new magnetic model was used where this kind of interaction was also considered. The resulting fitting parameters are the following: Gzz = 0.25 cm(-1), delta = 2.5 cm(-1), and TIP = 550 x 10(-6) emu mol(-1). For complex 2, the experimental data could be satisfactorily reproduced by using an isotropic exchange model, H = -2J1(S1S2 + S1S3) - 2J2(S2S3) with J1 = -7.44 cm(-1), J2 = -51.98 cm(-1), and g = 1.99. The magnetization data allows us to deduce the ground term of S = 1/2, characteristic of equilateral triangular chromium(III) for complex 1 and S = 3/2 for complex 2, which is confirmed by EPR measurements.  相似文献   

19.
[PrAl(CF3COO)2(CF3CHOO)(C2H5)2(C4H8O)2]2 Mr=1420.56, monoclinic, P21/n, a=10.651(6), b=24.276(9), c=11.110(5)(), β=107.650(4)°, V=2737.4(1)()3, Z=2, Dc=3.45 g/cm3, F(000)=2816, T=233K, MoKα radiation (λ=0.71069()), μ(MoKα)=38.017 cm-1, R=0.048 for 2847 observed reflections (I≥3σ(I)). It is isostructural with [LnAl(CF3COO)2(CF3CHOO)-R2(C4H8O)2]2 (Ln=Ho, R=Et; Ln=Nd, Y, R=iBu). Pr3+ is coordinated by eight oxygen atoms from five bridging ligands and two THF forming a distorted bicap-prism.  相似文献   

20.
在水-乙醇混合体系中, 将浓硝酸硝化的Sm2O3与1,10-邻菲啰啉反应, 用冰醋酸调节pH≈4, 形成醋酸根桥联的双核钐配合物[Sm2(CH3COO)4(NO3)2(phen)2](phen=1,10-邻菲啰啉), 用元素分析、红外光谱和核磁共振谱等进行了表征, 并用X射线衍射测定了配合物的晶体结构, 此外, 对配合物进行了非等温热分解动力学研究. 该晶体属于三斜晶系, P1空间 群, 晶胞参数a=0.979 6(3) nm, b=0.981 3(4) nm, c=1.127 3(4) nm, α=106.666(5)°, β=113.034(5)°, γ=102.656(5)°, V=0.885 4(5) nm3, Z=1, μ=3.361 mm-1, Dc=1.915 g/cm3, F(000)=498, R1=0.059 6, wR2=0.144 8. 该配合物是双核分子, 2个Sm(Ⅲ)离子通过4个醋酸根的羧基桥联, 每个中心离子分别与周围5个来自羧基的桥氧原子、 一个硝酸根的两个氧原子和一个邻菲啰啉分子中的两个氮原子配位, 形成九配位扭曲多面体. 非等温热分解动力学研究结果表明, 配合物第一步热分解反应可能为二级反应, 其动力学方程为dα/dT=A/[βe-E/RT(1-α)2], 分解反应的表观活化能为344.84 kJ/mol, 指前因子lnA=66.52.  相似文献   

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