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1.
Solid-state reaction of praseodymium (III) oxide,K2CO3 and MoO3 at high temperature leads to a potassium lanthanide double molybdate,namely,KPr(MoO4)2. The structural and optical properties of the title compound have been investigated by means of single-crystal X-ray diffraction and spectroscopic measurements at room temperature. KPr(MoO4)2 crystallizes in tetragonal,space group I41/a with a = 5.401(3),c = 12.044(10),Z = 2 and R (I 〉 2σ(I)) = 0.0416. It features the famous scheelite-type structure (CaWO4),which can be thought as the substitution of two Ca^2+ ions in CaWO4 by a couple of K^+ and Pr^3+ ions in a statistical manner,and W^6+ by Mo^6+ cations.  相似文献   

2.
RbMnO2 was prepared via the azide/nitrate route. Stoichiometric mixtures of the precursers (Mn2O3, RbN3 and RbNO3) were heated in a special regime up to 600 °C and annealed at this temperature for 30 h in specially designed silver crucibles. Single crystals have been grown by annealing a 1:1 mixture of Rb2O and MnOx at 585 °C for 1200 h. According to the crystal structure determination Mn3+ is in a square‐pyramidal coordination by oxygen. These [MnO5] units form double chains extending along the crystallographic c‐axis. RbMnO2 shows Curie‐Weiss behaviour down to ~ 100 K. A fit of the susceptibility data yields an average value of the magnetic moment (per manganese atom) of μeff = 5.33 μB, and θp = –820 K. At 50 K and low field strength onset of ferromagnetic order due to spin canting has been observed.  相似文献   

3.
In search of environmentally benign insecticides with high activity, low toxicity and low resistance, a series of novel anthranilic(isophthalic) acid esters was designed and synthesized based on the structure of ryanodine modulating agent. All the compounds were characterized by 1H NMR spectra, elemental analysis or high resolution mass spectrometry(HRMS). The preliminary results of biological activity assessment indicate that some of the title compounds exhibit certain but unremarkable insecticidal activity against Mythimna separata Walker at 200 mg/L and fungicidal activities against five funguses at 50 mg/L.  相似文献   

4.
马恩  江海龙 《结构化学》2007,26(10):1159-1164
TbCu(TeO3)2Cl was obtained in high yield from high temperature solid-state reac-ion of Tb4O7,CuO,CuCl2 and TeO2 in a 1:2:2:8 molar ratio at 710 ℃ in an evacuated quartz tube. Its structure was established by single-crystal X-ray diffraction. The title compound crystal-lizes in monoclinic,space group P21/c,with a=5.409(2),b=14.994(6),c=9.183(4),β= 98.884(5)°,V=735.8(5) ?3 and Z=4. TbCu(TeO3)2Cl is isostructural with LnCu(TeO3)2X (Ln= Dy,X= Cl; Ln=Er,X=Cl,Br). Its structure features a three-dimensional (3D) network built from Tb(Ⅲ) and Cu(II) ions interconnected by tellurite and chloride anions; the chloride anion and the lone-pair electrons of the tellurium(IV) ions are oriented toward the cavities of the tunnels in the network. Solid-state luminescent spectrum of TbCu(TeO3)2Cl shows a strong emission band at 545 nm with a luminescent life time of 291 μs.  相似文献   

5.
A novel ligand N-ethyl-1,10-phenanthroline-2-methanamine and its Ni(Ⅱ) complex have been synthesized. The crystal structure of the complex has been determined by X-ray diffraction method. The Ni(Ⅱ) is five-coordinated by three nitrogen atoms from the ligand and two Cl- anions in a distorted trigonal bipyramidal environment: the N(2), Cl(1) and Cl(2) in equatorial plane; the N(1) and N(3) in axial positions. The UV-spectra and IR-spectra of the ligand and its Ni(Ⅱ) complex were recorded and discussed. The thermodynamic properties of the ligand with various bivalent metals were studied by potentiometric titrations and the order of the stability constants is in agreement with the Irving-Williams order in coordination chemistry. CCDC: 221750.  相似文献   

6.
配合物Cu(3,5-DMBA)2(phen)的合成、晶体结构及电化学性质   总被引:2,自引:0,他引:2  
A copper(Ⅱ) complex Cu(3,5-DMBA)2(phen) has been synthesized by self-assembly of 3,5-dimethylbenzoic acid, 1,10-phenanthroline and copper perchlorate. Crystal data for this complex: Monoclinic, space group C2/c with a=2.348 3(5) nm, b=0.984 4(2) nm, c=1.138 4(2) nm, β=103.02(3)°, V=2.563 9(9) nm3Dc=1.404 g·cm-3, Z=4, F(000)=1 124, final GooF=1.051, R1=0.035 0, wR2=0.099 8. The crystal structure shows that the copper atom is coordinated with two oxygen atoms from two 3,5-dimethylbenzoic acids and two nitrogen atoms from the 1,10-phenanthroline, forming a square-planar structure. The result of the cyclic voltametric behavior analysis shows that the electron transfer in electrode reaction is quasi-reversible. CCDC: 650387.  相似文献   

7.
The reaction of a mixture of barium and rhenium (3:1) at 850 °C under flowing nitrogen yielded the nitride‐oxide (Ba6O)(ReN3)2 (R (No. 148); a = 8.1178(2) Å, c = 17.5651(4) Å; V = 1002.43(5) Å3; Z = 6). According to a structure refinement on X‐ray powder diffraction data, this compound is isostructural to a recently described nitride‐oxide of osmium of analogous composition. The structure consists of sheets of trigonal ReN3 units and trigonal antiprismatic Ba6O groups. The Ba–O distance of 2.73 Å is close to the sum of the respective ionic radii. The trigonal ReN35– nitride anion displays a Re–N bond length of 1.94 Å, and is planar within the limits of experimental error. The constitution of the anion was confirmed by IR and Raman spectroscopy. The nitride‐oxide is stable up to 1000 °C, semiconducting (σ = 4.57 × 10–3 Ω–1 · cm–1 at RT), and paramagnetic down to 25 K. A Curie–Weiss analysis resulted in a magnetic moment of μ = 0.68 μB per rhenium atom.  相似文献   

8.
Na2MnO2 was prepared via the azide/nitrate route. Stoichiometric mixtures of the precursors (Mn2O3, NaN3 and NaNO3) were heated in an appropriate regime up to 390 °C and annealed at this temperature for 20 h, in specially designed silver containers. As the most prominent feature, the crystal structure of Na2MnO2 (C2/c, Z = 12, a = 12.5026(9), b = 12.1006(9), c = 6.0939(4) Å, β = 117.94(0)°, 1556 independent reflections, R1 = 3.83 % (all data)) forms a three dimensional framework polyanion of corner sharing MnO4‐tetrahedra. The connectivity pattern of the tetrahedral building units corresponds to the moganite structure, a rare SiO2 modification. According to measurements of the magnetic susceptibility in the temperature range from 2 to 750 K, Na2MnO2 shows antiferromagnetic ordering below 250 K. Evaluation of the high temperature data employing the Curie‐Weiss law revealed a magnetic moment of μeff = 5.93 μB, confirming the presence of divalent manganese.  相似文献   

9.
采用溶剂扩散法获得了锰(III)的两个单核配合物 [Mn(Miao)2(H2O)2]ClO4(1)和[Mn(Miao)2(DMF)2]ClO4(2)(HMiao = 1-甲基-2-咪唑醛肟,DMF = N,N-二甲基甲酰胺)的晶体。X-射线衍射单晶结构表明:两种配合物均属三斜晶系,空间群Pī,锰与配位原子形成稳定的八面体结构。采用Gaussian03W程序计算了HMiao配体的电荷密度,理论计算与实际配位形式完全吻合。通过循环伏安法测定了两种锰配合物在DMF 溶液中的电化学性质。  相似文献   

10.
1 INTRODUCTION a-Hydroxyphosphonic acids and their esters are known to possess broad-based physiological activities and there is close links between biological efficacy and stereochemistry[1~3]. Optical active a-hydroxyphosphonic esters can also serve as useful precursors in organic synthesis[4, 5]. Here we will report the synthesis of optical active a-hydroxyphosphinic acid, (+)-(a-hydroxybenzyl)- phenylphosphinic acid and its crystal structure and the absolute configuration of its a-ca…  相似文献   

11.
0IntroductionPhenanthrolinederivativescontainingaminegroupshavebothsoftandhardsitesandaregooddonorsformetalions.1,10鄄phenanthrolineanditsderivativeshavebeenextensivelyusedasligandsinbothanalyticalandpreparativecoordinationchemis鄄try[1].Mostoftheseworksh…  相似文献   

12.
Zn C6H8N2O5.H2O(NCGZn) has been synthesized, and its functional groups present in the title compound were confirmed by elemental analysis, TG and IR spectral studies. Meanwhile, the crystal of NCGZn was obtained by slow evaporation of a saturated aqueous solution at room temperature and confirmed by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P21 with a = 5.03220(1), b = 13.3747(4), c = 12.9944(4), β = 92.987(2)°, V = 873.39(4)3, Z = 2, C12H20N4O12Zn2, Mr = 543.10, Dc = 2.065 g/cm3, F(000) = 552, μ(Mo Ka) = 2.826 mm-1, R= 0.0422 and w R = 0.1142. In NCGZn, Zn1 and the symmetry formed Zn1 ions are connected by five atoms from four NCG-2H anions and a water molecule. A NCG ligand has two carboxylate groups, one connecting a Zn ion, and the other bridgiong two Zn ions. The NCG ligand bridges four Zn ions through the amino group and two carboxylate groups with a water molecule to yield a 3D coordination polymer structure with hydrogen bonds.  相似文献   

13.
Li2CuII5(PO4)4 has been obtained by various reactions starting from copper or Cu2O. Crystallization was achieved using I2 as oxidant and mineralizer. The new orthophosphate crystallizes in space group P$\bar{1}$ , Z = 2, with a = 6.0502(3) Å, b = 9.2359(4) Å, c = 11.4317(5) Å, α = 75.584(2)°, β = 80.260(2)°, γ = 74.178(2)°, at 293 K. Its structure has been determined from X‐ray single‐crystal data and refined to R1 = 0.022{wR2 = 0.058 for 4633 unique reflections with Fo > 4σ (Fo)}. From magnetic measurements μeff = 1.51 μB/Cu and θP = –37.4 K have been determined. The Vis/NIR spectrum of aqua‐green Li2Cu5(PO4)4 shows a single broad band centered around $\bar{1}$ = 12000 cm–1. Magnetic behavior and spectrum are discussed within the angular overlap model.  相似文献   

14.
Blue, paramagnetic bis(phthalocyaninato(2–)rhenium(II)) (μeff = 0,88 μB, per Re, at 300 K) is prepared by thermal decomposition of trans-bis(triphenylphosphine)phthalocyaninato(2–)rhenium(II), in boiling triphenylphosphine. It crystallizes in the triclinic space group P 1 with cell parameters as follows: a = 7.799(3) Å, b = 12.563(7) Å, c = 12.69(1) Å, α = 89.97(5)°, β = 94.14(5)°, γ = 106.39(4)°; Z = 1. Two cofacial phthalocyaninates are bonded together by a Re–Re bond with a Re–Re distance of 2.285(2) Å. The Re atoms are located distinctly outside the centre of the (Niso)4 planes by 0.426(3) Å. The Re–Niso distance varies from 1.99(1) to 2.04(1) Å (average 2.02 Å). The pc2– ligands are in an eclipsed conformation and concavely distorted. In the UV-VIS-NIR spectrum the B region is split into two bands of comparable intensity due to strong excitonic coupling. The Re–Re stretching vibration at 240 cm–1 is selectively enhanced in the resonance Raman spectrum (λexc = 488 nm).  相似文献   

15.
Reaction of Mn(NCS)2 with 4-picoline (4-methylpyridine) leads to the formation of [Mn(NCS)2(4-picoline)4] · 0.67 · 4-picoline · 0.33 · H2O ( 1 - Mn ) reported in literature, Mn(NCS)2(4-picoline)2(H2O)2 ( 2-Mn/H2O ), and of [Mn(NCS)2(4-picoline)2]n ( 2-Mn/I ). 1-Mn and 2-Mn/H2O consist of discrete complexes, in which the metal cations are octahedrally coordinated, whereas in 2-Mn/I the metal cations are linked by pairs of μ-1,3-bridging thiocyanate anions into corrugated chains. Measurements using thermogravimetry and differential scanning calorimetry as well as temperature dependent X-ray powder diffraction on 1-Mn and 2-Mn/H2O reveal that upon heating both compounds transform into [Mn(NCS)2(4-picoline)]n ( 3-Mn ) via 2-Mn/I as intermediate. 3-Mn shows a very rare chain topology in which the metal cations are linked by μ-1,3,3 (N,S,S) coordinating anionic ligands which was never observed before with MnII. From these investigations there is no hint that a further modification of 2-Mn can be prepared as recently observed for [M(NCS)2(4-picoline)2]n (M = Fe, Cd) and such a form is also not available if the metastable forms of the FeII or CdII compounds were used as template during thermal decomposition. Magnetic investigations on 2-Mn/H2O show only paramagnetic behavior, whereas for 2-Mn/I antiferromagnetic ordering is observed. Finally, the crystal structure of Mn(NCS)2 was determined from XRPD data, which shows that it is strongly related to that of 3-Mn .  相似文献   

16.
Two polyamine copper(II) complexes were synthesized by the reaction between N,N,N′,N′-tetrakis(2′-aminoethyl)propane-1,2-diamine hexahydrochloride and copper(II) perchlorate under almost the same conditions except for reaction temperature. The crystal structures of two complexes were determined by X-ray diffraction techniques, which shows that one of the complexes is unexpected and is a double chlorine or chloride-bridged dinuclear copper(II) complex formed by two diethylenetriamines, and another is a pentadentate mononuclear copper(II) complex composed of homo-protonated N,N,N′,N′-tetrakis(2′-aminoethyl)propane-1,2-diamine. The mechanism of the reaction leading to form the unexpected complex was discussed. The UV-visible spectra and cyclic voltammogram of the complexes were measured.  相似文献   

17.
本文合成了1个新的铜双核配合物[(CuI)(PMN)]2.2CH3CN(PMN=2、4-二氨基-5-氯苯基-6-乙基嘧啶),并且通过元素分析、红外、荧光、热重和单晶X-射线进行了表征。该配合物属三斜晶系,空间群P1,a=0.8100(16)nm,b=0.96950(19)nm,c=1.2049(2)nm,α=97.88(3)°,β=93.31(3)°,γ=94.14(3)°,V=0.933 8(3)nm3,Z=1,R=0.037 1。在配合物中,每个Cu(Ⅰ)离子与PMN配体的1个N原子和2个I原子配位,展示出三角几何构型。相邻的2个Cu(Ⅰ)离子通过碘原子相连形成双核铜配合物,并进一步通过氢键和I…I作用形成三维网状结构。  相似文献   

18.
A novel tetranuclear nickel(Ⅱ) complex [Ni4L2(DMF)2(H2O)2·2DMF] (1,H4L=azo-enolic-2-hydroxybenzamide, DMF=N,N-dimethyl-formamide) has been synthesized and characterized by elemental analysis, UV, IR and X-ray single-crystal diffraction characterization. Complex 1 crystallizes in the monoclinic system, space group P21/n with a=8.8944(11), b=14.4583(18), c=18.097(2) , β=90.00(2)o, Z=2 , V=2327.2(5)3 , C40H48N12Ni4O14 , Mr=1155.66, Dc=1.649g/cm 3 , μ=1.672 mm-1 , F(000)=1192, R=0.0392 and wR=0.0958. The local coordination environment around the nickel ions exist a distorted octahedral and quadrangle geometry in the molecular structure. Complex 1 exhibits strong photoluminescent emission in the ultraviolet region at room temperature. The electrochemical studies reveal that redox of Ni 3+ /Ni 2+ in the complex is a quasi-reversible process.  相似文献   

19.
The title compound (+)-((-hydroxybenzyl)phenylphosphinic acid (C13H13O3P, Mr = 248.20) has been synthesized and characterized by 31P NMR, 1H NMR and elemental analysis. X-ray diffraction analysis at 293(2) K indicates that the compound belongs to monoclinic system, space group C2 with cell parameters: a = 23.560(8), b = 6.947(2), c = 7.854(3) (A。), β = 91.273(6)°, V = 1285.2(7) (A。)3, Z = 4, Dc = 1.283 g/cm3, F(000) = 520 and ((MoK() = 0.207 mm-1. The number of independent reflections amounts to 1991, of which 1507 are observed reflections. The crystal structure has been determined by direct methods (SHELXL-97). The structure parameters are refined by full-matrix least-squares on F2 to R = 0.0437 and wR = 0.0893. The flack x parameter is - 0.0001. The absolute configuration of the (-carbon in the title compound is S.  相似文献   

20.
Recently,tremend0useffortshavebeendevotedtosynthesisof0rgan0metalliccomp0undswithlargesecondorder0pticaln0nlinearities."2'3H0wever,fewofthemcanbeusedasapplicablematerials,owingtotheintensecolorofmosttransitionmetalcomplexes.Andwef0undthatthatpalecolormetalcomplexesderivedfromthiosemicarbazonemightbethepossiblewaytoobtainthenonlinearopticalcompoundwhichcouldbeusedasaPplicablematerials.InthispaPer,2-chlorobenzaldehydethiosemicarbazoneligandhasbeendesignedandsynthesized,thecomplexofcadmiumbromid…  相似文献   

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