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1.
The UV/VIS spectra for pyridine solution of complexes [Fe_2MO(CH_3COO)_6Py_2]·Py and THF solution of complexes Fe_2MO(CCl_3COO)_6(THF)_3 were studied. The d-d transitions were assigned and the ligand field parameters(B,D_q,β) were calculated for the related metal ions according to ligand field theory (Tanabe-Sugano diagram) in terms of O_h symmetry and reasonably good fits were obtained for the calculated and observed frequencies. The calculated results show that (1) the larger the ionic potential for M~(2+) ion, the larger the values of B, D_q for Fe~(3+) ion (2) the ligand field parameters of metal ions vary in parallel with the electronagativity of R in RCOO~-.  相似文献   

2.
Two new title compounds have been prepared in powder form. Their spectral data are found to be consistent with the structure foundin Hofmann-Td-type clathrates.  相似文献   

3.
报导了对配合物M(bpy)2 M=Fe,Ru,Os)的量子化学密度泛函(DFT)法研究的结果.在B3LYP/LanL2DZ方法与基组的水平上进行计算 ,探讨M(bpy)32 的电子结构特征及相关性质 ,特别是中心原子对配合物的配位键长、光谱性质、电荷布居及化学稳定性等的影响规律 ,为该类配合物的合成 ,为分析光、电、催化作用机理提供理论参考.  相似文献   

4.
氧心羧桥三核物通式为[M_3O(RCOO)_6L_3]~(n+)(n=1,0)虽然它在三十年代就已合成出来,但是引起人们广泛兴趣的还是近年来发现的它所具有的特殊稳定性和不寻常的物理化学性质。我们测定了不同M~(2+)离子,两种羧桥的铁系列异三核标题簇合物的晶体结构和有关物理性质。该类型化合物的结构可以看成由共享μ_3-O顶点的三个金属离子的配位八面体组  相似文献   

5.
Compounds [M(μ-O2C-C6H4-CO2)(NH3)2] crystallize as straight- (M = Cu) and kinked-chain (M = Cd) coordination polymers through the bridging action of the bis-mono (Cu) and bis-bidentate (Cd) benzene-1, 4-dicarboxylate (terephthalate) ligand. N-H···O hydrogen bonding connects the chains to a three-dimensional supramolecular network. Thermogravimetry shows the compounds to be stable up to 255 °C (M = Cu) and 70 °C (M = Cd) where decomposition starts with the loss of one ammin ligand. [Cd(μ-O2C-C6H4-CO2)(NH3)2] exhibits a luminescence with λem, max = 392 nm (λex = 240 nm) on the same order of magnitude as Na2(O2C-C6H4-CO2).  相似文献   

6.
本文研究了Eu2+离子在MyAlxBOy+3/2(1+x)(M=Ca,Sr,Ba)基质中的发光性质及磷和卤素对发光的影响。 采用以H2和N2混合气体为还原气氛在高温下进行固相反应的方法合成了一系列磷光体。发现,在CaAlxBO2.5+3/2x基质中,当X在0.5~2的范围内时及在SryAl2BO4 6+基质中,当y在2~6的范围时掺入的Eu3+不能被H2还原为Eu2+。其他Eu2+激活的磷光体一般都产生f~d跃迁的宽带发射,发射峰的波长随着基质组成的不同可在400~600nm的区间的变化。  相似文献   

7.
The reactions of the group 15 trihalides, MX(3) (M = As, Sb, Bi; X = Cl, Br), with the phosphine selenide SeP(p-FC(6)H(4))(3) result in the formation of co-crystals of formula MX(3)·SeP(p-FC(6)H(4))(3). No reaction was observed with MI(3) (M = As, Sb, Bi). The structures of MX(3)·SeP(p-FC(6)H(4))(3) (M = As, X = Br 2; M = Sb, X = Cl 3; M = Bi, X = Cl 5; M = Bi, X = Br 6) have been established, and are isomorphous, crystallising in the cubic I23 space group. All the structures feature a primary MX(3) unit, which has three weak secondary MSe interactions to SeP(p-FC(6)H(4))(3) molecules. However, each of these SeP(p-FC(6)H(4))(3) molecules bridges three MX(3) molecules, resulting in the generation of an M(4)Se(4) (M = As, Sb, Bi) distorted cuboid linked by the pnictogen-chalcogen interactions. Four opposing corners of the cuboid are occupied by the M atom (M = As, Sb, Bi) of an MX(3) pyramid, and the other four by the selenium atom of the phosphine selenide.  相似文献   

8.
The complex compound of copper(II) nitrate with 1ethyltetrazole (ettz), Cu( C3H6N4)2(NO3)(NO3)2/2] is studied by Xray diffraction analysis (“Syntex P21” automatic diffractometer, CuKa radiation, graphite monochromator, 6/26 scan mode with Vmin = 3.91 deg/min, the total number of data collected 3544 lhkb including 3141 nonextinct lhkl > 0, a correction for absorption (Μ = 25.08 cm-1) applied by integrating over the crystal faces). The parameters of the orthorhombic unit cell (space group Pccn) are a = 15.436(3), b = 20.198(5), c = 19.587(3) Å, Vcell = 6107(2) Å3, Z = 16, dcalc = 1.670 g/cm3. The two crystallographically independent copper atoms have a distorted octahedral environment (coordination node is CuN2O4), coordination number (CN) is 6 = 4 + t2. In the equatorial plane, two nitrogen atoms of ettz and two oxygen atoms of NO 3 ? groups are trans to each other; Cu-N = 1.983(8), C-ONO 3 ? = 1.978(7) Å (average). The nitrato groups fulfill chelate and bridging functions, complementing the coordination polyhedra of the copper atoms to distorted octahedra, where Cu-ONO 3 ? = 2.517(7) Å (average). The compound has a chain structure; the chains stretching along [001] are packed pairwise according to the hexagonal law.  相似文献   

9.
本文用水热法合成了2个稀土配位聚合物[M(yddc)(NO3)(H2O)4]·2H2O[M=Eu(1),M=Dy(2)],并对它们进行了元素分析、红外光谱、热重等分析,研究了它们的荧光性质,并用X-射线单晶衍射测定了配合物的单晶结构.两者的晶系都属于三斜晶系,P1空间群.荧光实验表明配合物1在常温下具有很强的荧光.  相似文献   

10.
[M(en)3]2Sn2Se6(M=Mn,Zn)的制备及其热稳定性   总被引:4,自引:0,他引:4  
陈震  王如骥 《物理化学学报》1999,15(12):1070-1075
用有机溶剂热生长技术(SolvothermalTechnique)制备过渡金属锰和锌硒化物[Mn(en)3]2Sn2Se6(Ⅰ),[Zn(en)3]2Sn2Se6(Ⅱ).用单晶X射线衍射技术对其进行晶体结构分析.[Zn(en)3]2Sn2Se6样品的热分析结果表明,该化合物的热分解分三步进行.光学性质测试表明它们是半导体材料,[Mn(en)3]2Sn2Se6的能带隙为1.76eV.[Zn(en)3]2Sn2Se6的能带隙为2.49eV.  相似文献   

11.
<正> The title compounds have been synthesized and characterized by x-ray analysis. They are isomorphous, belonging to trigonal space group R3m,with crystallo-graphic parameters; (1)α =b =c= 13. 713(5) A ;α= β=γ=83. 66(3)°;V = 2535A3;Z = 2;DC=1. 80gcm-3;F(000) = 1358;M= 1373. 23;(2)α= b = c=13. 687(2) A;α = β = γ = 84. 27(1)°/;V = 2528. 0A3;Z = 2; Dc = 1. 81gcm-3; F (000)= 1362; M = 1377. 23;(3)α = b=c=13. 671(6) A ;α = β = γ=84. 12(3)°;V=2518A3;Z=2;DC = 1. 82 gcm-3;F(000)= 1364;Mr= 1376. 99.The structure of comp ound 2 has been determined with the final R= 0. 061 for 845 reflections with I≥3σ(Ⅰ).The three metal atoms are crystallographically equivalent because of the arbitrariness of orientation of the molecules,and in the sense of crystallography the molecule Fc2CoO(O2CCCl3)6(THF)3 is of C3vsymmetry with centered oxygen atom on the 3-fold axis. The atoms M,C(1~4),C1(1) and O(1) lie on the mirror. Three CC13 groups on one side the Fe2CoO plane and three terminal THF ligands are dynamically  相似文献   

12.
13.
X-ray crystallographic analysis is used to determine the crystal structures of [Ru(NH3)6](MoO4)Cl·3H2O and [M(NH3)6](ReO4)3·2H2O (M = Ru, Ir) complex salts. The features of the fragment packing are studied.  相似文献   

14.
Synthesis of complexes(η~5-CH_3C_5H_4)M(CO)_2NO(M=Mo,I;M=W,II)and clusters(η~5-CH_3C_5H_4)M(μ~3-NH)(μ~2-NO) (μ~2-CO)Fe_2(CO)_6(M=Mo,III:M=W,IV),based on the reaction of (η~5-C5_H_4)M(CO)_3Cl with Na[Fe(CO)_3NO] at room tem-perature,have been demonstrated,The crystal structures of II and IV arealso presented.  相似文献   

15.
测定了(p-CH3OC6H4)2TeO存在下M2(CO)10(M=Mn,Re)的CO取代反应速率及活化参数。其表观速率常数分别与M2(CO)10和(p-CH3OC6H4)2TeO的浓度的一次方成正比。本文所建议的缔合机理与前人用(CH3)3NO作氧原子转移试剂的相应反应所提出的机理相似。讨论了在(CH3)3NO和(p-CH3OC6H4)2TeO存在下影响M2(CO)10的CO取代反应速率的因素。  相似文献   

16.
The structure of the fully ordered α-Na(3)Ti(2)(PO(4))(3) NASICON compound was elucidated using high-quality single-crystal data. The cation/vacancy distribution forms a homogeneous 3D arrangement and could represent the absolute cationic ordering available in the full Na(3)M(2)(PO(4))(3) series, as verified for M = Fe. For M = Ti, the reversible α → γ transition was observed at 85 °C, leading to the standard disordered R ?3c γ model. Through JPDF analysis, the most probable Na(+) zigzag M(2)-M(1) diffusion scheme was directly deduced using our accurate crystallographic data.  相似文献   

17.
利用溶剂热法合成了2种新的有机杂化锑硒化合物[Ni(dap)3]2(Sb2Se5)].2H2O(1)和[Zn(dap)3]2(Sb2Se5)](2)(dap=1,2-丙二胺),单晶X射线衍射分析结果表明,1属于三方晶系,P3121空间群,晶胞参数为a=10.7574(14),b=10.7574(14),c=31.672(4),γ=120.00°,z=4。2属于单斜晶系,P21空间群,晶胞参数为a=10.772(2),b=16.391(3),c=11.704(2),β=100.912(4)°,z=4。在2种化合物中,Ni2 与Zn2 离子分别与3个dap配体螯合形成畸变八面体几何构型,其中dap配体的N原子是无序的,而二聚[Sb2Se5]2-阴离子是由2个SbSe3三角锥共用1个Se原子连接而成。  相似文献   

18.
A comparison of the electrochemical properties of a series of dinuclear complexes [M(2)(L)(RCO(2))(2)](+) with M = Mn or Co, L = 2,6-bis(N,N-bis-(2-pyridylmethyl)-sulfonamido)-4-methylphenolato (bpsmp(-)) or 2,6-bis(N,N-bis(2-pyridylmethyl)aminomethyl)-4-tert-butylphenolato (bpbp(-)) and R = H, CH(3), CF(3) or 3,4-dimethoxybenzoate demonstrates: (i) The electron-withdrawing sulfonyl groups in the backbone of bpsmp(-) stabilize the [M(2)(bpsmp)(RCO(2))(2)](+) complexes in their M(II)(2) oxidation state compared to their [M(2)(bpbp)(RCO(2))(2)](+) analogues. Manganese complexes are stabilised by approximately 550 mV and cobalt complexes by 650 mV. (ii) The auxiliary bridging carboxylato ligands further attenuate the metal-based redox chemistry. Substitution of two acetato for two trifluoroacetato ligands shifts redox couples by 300-400 mV. Within the working potential window, reversible or quasi-reversible M(II)M(III)? M(II)(2) processes range from 0.31 to 1.41 V for the [Co(2)(L)(RCO(2))(2)](+/2+) complexes and from 0.54 to 1.41 V for the [Mn(2)(L)(RCO(2))(2)](+/2+) complexes versus Ag/AgCl for E(M(II)M(III)/M(II)(2)). The extreme limits are defined by the complexes [M(2)(bpbp)(CH(3)CO(2))(2)](+) and [M(2)(bpsmp)(CF(3)CO(2))(2)](+) for both metal ions. Thus, tuning the ligand field in these dinuclear complexes makes possible a range of around 0.9 V and 1.49 V for the one-electron E(M(II)M(III)/M(II)(2)) couple of the Mn and Co complexes, respectively. The second one-electron process, M(II)M(III)? M(III)(2) was also observed in some cases. The lowest potential recorded for the E°(M(III)(2)/M(II)M(III)) couple was 0.63 V for [Co(2)(bpbp)(CH(3)CO(2))(2)](2+) and the highest measurable potential was 2.23 V versus Ag/AgCl for [Co(2)(bpsmp)(CF(3)CO(2))(2)](2+).  相似文献   

19.
The new cubane cluster complex K6[Ta4(4-O)(3-Te)4(CN)12]·KOH·4H2O was prepared from a mixture of TaTe4 and KCN by the high-temperature synthesis followed by crystallization from aqueous solutions. The compound was characterized by cyclic voltammetry, X-ray diffraction analysis, and IR, Raman, and electronic spectroscopy. A comparative study of the clusters [M4(4-O)(3-Te)(CN)12]6– (M = Nb or Ta) containing the 4-O ligands was carried out. These clusters are the first molecular chalcogenide cubane complexes of Group V metals.  相似文献   

20.
The reactions of [Bt3NH][μ-CO)(μ-RS)Fe2(CO)6] (1a-d) (R=nPr,nBu,tBu, Ph) with p-MeC6H4C=CPh or m-NO2C6H4C=CPh were studied and products of the vinyl type (μ-σ,π-p-MeC6H4C=CHPh)(μ-RS)Fe2(CO)6 (2) and (μ-σ,π-phC=CHC6H4Me-p) (μ-RS)Fe2(CO)6 (3) (R=nPr, nBu, tBu, Ph) were obtained. While the structures of all the compounds 2a-d and 3a-d were characterized by elemental analysis, IR,1H NMR and MS spectroscopies, the single-crystal structure of 2c(R=tBu) was determined by X-ray diffraction method. The X-ray dim-action result of 2c showed that the substituted vinyl ligand p-MeC6H4C=CHPh bridges the two uon centers, being σ-bonded to one metal through the olefinic carbon attached to p-MeC6H44 group, while π-bonded to the other via olefinic linkage; the Fe2(CO)6 and proton units are in a cis fashion and the tBu group is bonded to sulfur atom through an e-type of bond.  相似文献   

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