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1.
采用准刚性的双吡啶化合物3,7-di(3-pyridyl)-1,5-dioxa-3,7-diazacyclooctane (L),合成了4个过渡金属配合物[Co(NO_3)(H_2O)_2(L)_2]NO_3 (1)、[Co_2Cl_4(L)_2]·CH_2Cl_2 (2)、[Cd_2(AcO)_4(L)_2]·4CH_3OH (3)和[Cd_2(NO_3)_2(CH_3OH)_2(H_2O)_2(L)_2](NO_3)_2·2H_2O (4)。单晶衍射分析表明,配合物1是单核结构,配合物2是24-元环状双核结构,而配合物3和4为多边形双核结构。在这些配合物中,双吡啶配体分别采用了单齿、trans-和cis-桥连3种不同配位方式。配合物经过了元素分析、红外、热重和X射线单晶结构分析表征。  相似文献   

2.
通过配体1,2-环己二胺缩邻香兰素(H2L)和不同的镱盐反应,合成了4个镱稀土配合物[Yb(H_2L)_2](ClO_4)_3·2CH_3OH·H_2O(1),[Yb_4(L)_4(NO_3)2(H_2O)_2](PF_6)_2·4CH_3CN(2),[Yb_4(L)_4(H_2O)_2Cl_2](PF6)_2·2CH_2Cl_2·2H_2O(3)和[Yb_4(L)_4(NO_3)_2(H2O)_2][Yb(NO_3)_3(H_2O)_2(CH_3OH)](NO_3)_2·4CH_2Cl_2·6CH_3OH(4)。X射线单晶衍射分析表明配合物1为零维的单核结构,配合物2~4均为四核结构。研究了4个配合物的近红外发光性能。  相似文献   

3.
本文合成了硝酸钴(Ⅱ),氯化钴(Ⅱ),硫氰酸钴(Ⅱ)与内、外消旋的双(正-丙基亚砜)乙烷(以A表示)六个固体配合物:[Co_2(α-A)_3Cl_4]·H_2O、[Co(β-A)_2(NO_3)_2)·H_2O、[Co(β-A)_2(NO_3)_2]、[Co_2(α-A)_2(SCN)_4]·2H_2O和[Co(β-A)_2(SCN)_2](α-A和β-A各是外、内消旋的C_3H_7S(O)(CH_2)S(O)C_3H_7)。由元素分析、红外光谱、磁化率、电导及离子交换等研究结果表明配体A以二个氧原子与Co(Ⅱ)配位形成七元环的配合物。并确定Co_2(α-A)_3Cl_4为[Co(α-A)_3][CoCl_4]的配合物。初步认为[Co(α-A)(NO_3)]NO_3·H_2O为畸变的四面体配合物。其余四个配合物均为高自旋、畸变八面体,它们的结构可能是:及[Co(β-A)_2(SCN)_2]。对[Co(β-A)_2(NO_3)_2、[Co(β-A)_2(H_2O)_2](ClO_4)_2·H_2O及[Co(β-A)_2(SCN)_2]的Dq值计算结果表明NO_3~-、H_2O和SCN~-与Co(Ⅱ)配位符合配合物的光化序。  相似文献   

4.
2-(2,3-Dihydroxpropyliminomethyl)6-methoxyphenol(H_3L), trimethylacetic acid(Hpiv), Gd(NO_3)3·6 H_2O and Co(NO_3)2·6 H_2O were reacted in Me OH to obtain a heterometallic tetranuclear cluster [Gd_2Co_2(L)_2(μ_3-OH)_2(piv)_6]·2 Hpiv·2 CH_3OH(1). X-ray crystallographic analysis reveals that compound 1 was found to be a butterfly heterometallic tetranuclear cluster. The crystal(C_(64)H_(108)Co_2Gd_2N_2O_(28), Mr = 1785.88) belongs to the triclinic crystal system, space group P1 with a =11.9798(6), b = 12.0877(5), c = 15.0367(7) ?, α = 67.320(4)°, β = 81.583(4)°, γ = 75.201(4)°, V =1939.62(18) ?3, Z = 1, T = 293.15 K, R = 0.048 and w R = 0.144 for 16299 observed reflections with I 2σ(I). In magnetization study, heterometallic 1 exhibits magnetocaloric effect(MCE) of 14.75 J·kg~(-1)·K~(-1) at 2 K for ΔH = 5 T, while it does not show non-linear response of the ac-susceptibilities.  相似文献   

5.
通过2-(2′-羟基-3′-甲氧基)萘咪唑(HL)和Ln(NO)_3·6H_2O反应,合成了4种单核稀土配合物[Ln(HL)_2(NO_3)_3]·CH_2Cl_2(Ln=Sm(1),Eu(2),Tb(3))和[Ln(HL)_2(NO_3)_2(CH_3OH)]NO_3·CH_3OH(Ln=Yb(4))。X射线单晶衍射分析表明配合物1~4均通过配体萘环间的π-π作用呈现蝴蝶状结构。荧光性质表明仅有配合物4显示Yb3+稀土离子的特征发光,固态和在乙腈溶液中的荧光寿命分别为8.27μs和4.40μs。  相似文献   

6.
通过四水乙酸钴(Ⅱ)和Salamo型双肟配体4,4′-二硝基-2,2′-(1,2-乙二氧双(氮次甲基))二酚(H2L)在不同溶剂中的配位反应,合成了2种不同溶剂参与配位的三核钴(Ⅱ)配合物,即[Co_3L(OAc)_2(CH_3CH_2OH)_2]·2CH_3CH_2OH·2CHCl_3(1)和[Co_3L(OAc)_2(C_3H_7OH)_2](2),并通过元素分析、红外光谱、紫外-可见光谱和单晶X射线衍射法对其进行了性质表征。在配合物1和2中,存在2个配体单元(提供N_2O_2配位原子),2个乙酸根离子,2个配位的乙醇或正丙醇分子。虽然2个配合物是在不同溶剂中合成的,但配合物中的钴(Ⅱ)离子均采用稍微扭曲的八面体几何构型。结果表明,溶剂效应在配合物的配位环境中起了关键的作用。另外,配合物1和2在激发波长为450 nm时能表现出强烈的光致发光,其最大发射波长分别为568和566 nm。  相似文献   

7.
3,6-二(2-(4-氧化苯并吡嗪基))-4,5-二氮杂-3,5-辛二烯配体(L)与银盐室温下反应得到了2个结构新颖的离散型配位化合物[Ag_8(L)_8](BF_4)_8·CH_2Cl_2·3CH_3OH (1)和[Ag_4(L)_4](PF_6)_4·CH_2Cl_2(2)。通过红外、元素分析、X射线单晶衍射等检测手段对所得配合物进行了表征。结果表明,2个配合物皆以二聚体的形式存在。未配位的平衡阴离子与二聚体通过氢键连接成一维或二维结构。  相似文献   

8.
合成了2个化合物[Co~ⅡCo_4~Ⅲ(salhn)_4(N_3)_6(CH_3OH)_2(H_2O)_2]·4CH_3OH·2H_2O(1)和[Cu_2(salhn)(N_3)_2]_n(2)(H_2salhn=N,N′-bis(salicylidene)hydrazine),并用X射线单晶衍射进行结构表征。化合物1是一个五核的[Co~ⅡCo_4~Ⅲ]钴簇,而化合物2是一个具有结构单元为[Cu_2(salhn)(N_3)_2]的一维链结构。2个化合物中叠氮均具有end-on(EO,μ-1,1)的配位模式。化合物1和2的磁学性质测试表明它们都具有反铁磁行为。  相似文献   

9.
以三苯甲烷-4,4′,4″-三羧酸(H_3TCOPM)为主配体,以含氮二齿配体4,4′-bipyridine(4,4′-bipy)为辅助配体,与Co(NO_3)_2·6H_2O通过溶剂热反应得到了2个配位聚合物{[Co_2(α-OH-TCOPM)(OH)(H_2O)_4]·DMF}_n(1)(α-OH-H_3TCOPM=三苯甲醇-4,4′,4″-三羧酸)和{[Co_3(α-OH-TCOPM)_2(4,4′-bipy)_3(H_2O)_6]·2H_2O}_n(2)。晶体结构分析表明,配合物1为四边形的二维层状结构,而配合物2为二维网状结构。采用红外光谱、粉末X射线衍射对配合物进行了表征,用热重分析仪研究了其热稳定性。  相似文献   

10.
以3-甲氧基水杨醛与乙醇胺缩合得到席夫碱化合物hmmpH_2(hmmpH_2=2-[(2-羟乙基亚氨基)甲基]-6-甲氧基苯酚),以hmmpH_2为配体合成了配合物[Fe_2(hmmp)_2(hmmpH)_2]·1.5CH_3CN·0.5H_2O(1)和[Co_2Na(hmmp)_2(N_3)_2(CH_3O)(CH_3OH)_2](2)。以3,5-二溴水杨醛与乙醇胺缩合得到化合物hmdbrpH_2(hmdbrpH_2=2-[(2-羟乙基亚氨基)甲基]-4,6-二溴苯酚),以hmdbrpH_2为配体合成了一个混价三核配合物[Mn(Ⅱ)Mn(Ⅲ)_2(hmdbrp)_2(O_2CPh)_4(CH_3OH)_2]·2CH_3CN·2CH_3OH(3)(HO_2CPh为苯甲酸)。对配合物分别进行了元素分析、X射线单晶衍射分析,还对1和3进行了磁性研究。单晶结构分析表明配合物1中2个六配位的Fe(Ⅲ)离子通过2个醇羟基氧原子相连形成二聚体结构,配合物2中Co(Ⅲ)也为六配位,通过2个甲醇中氧原子相连形成双核结构,配合物3为一混价三核锰结构,3个Mn离子呈线性排列。磁性测试表明配合物1中Fe(Ⅲ)离子之间存在反铁磁相互作用,配合物3的三核锰单元内Mn(Ⅱ)、Mn(Ⅲ)离子之间存在反铁磁相互作用。  相似文献   

11.
The phase relations in the cross-section of the K2W2O7-K2WO4-KPO3 containing 15 mol% Bi2O3 were undertaken using flux method. Crystallization fields of K6.5Bi2.5W4P6O34, K2Bi(PO4)(WO4), Bi2WO6, KBi(WO4)2 and their cocrystallization areas were identified. Novel phase K6.5Bi2.5W4P6O34 was characterized by single-crystal X-ray diffraction: sp. gr. P−1, a=9.4170(5), b=9.7166(4), c=17.6050(7) Å, α=90.052(5)°, β=103.880(5)° and γ=90.125(5)°. It has a layered structure, which contains {K7Bi5W8P12O68} layers stacked parallel to ab plane and sheets composed by potassium atoms separating these layers. Sandwich-like {K7Bi5W8P12O68} layers are assembled from [W2P2O13] and [BiPO4] building units, and are penetrated by tunnels with K/Bi atoms inside. FTIR-spectra of K2Bi(PO4)(WO4) and K6.5Bi2.5W4P6O34 were discussed on the basis of factor group theory.  相似文献   

12.
K3InF6 is synthesized by a sol-gel route starting from indium and potassium acetates dissolved in isopropanol in the stoichiometry 1:3, with trifluoroacetic acid as fluorinating agent. The crystal structures of the organic precursors were solved by X-ray diffraction methods on single crystals. Three organic compounds were isolated and identified: K2InC10O10H6F9, K3InC12O14H4F18 and K3InC12O12F18. The first one, deficient in potassium in comparison with the initial stoichiometry, is unstable. In its crystal structure, acetate as well as trifluoroacetate anions are coordinated to the indium atom. The two other precursors are obtained, respectively, by quick and slow evaporation of the solution. They correspond to the final organic compounds, which give K3InF6 by decomposition at high temperature. The crystal structure of K3InC12O14H4F18 is characterized by complex anions [In(CF3COO)4(OHx)2](5−2x)− and isolated [CF3COOH2−x](x−1)− molecules with x=2 or 1, surrounded by K+ cations. The crystal structure of K3InC12O12F18 is only constituted by complex anions [In(CF3COO)6]3− and K+ cations. For all these compounds, potassium cations ensure only the electroneutrality of the structure. IR spectra of K2InC10O10H6F9 and K3InC12O12F18 were also performed at room temperature on pulverized crystals.  相似文献   

13.
phase diagrams of KCl-KBO2-K2CO3, K2MoO4-KBO2-K2CO3, and K2WO4-KBO2-K2CO3 ternary systems were studied by a calculation-experimental method and differential thermal analysis (DTA). The coordinates of ternary eutectics were determined to be E 1: 622°C, 8.5 mol % KBO2, 56.5 mol % KCl, and 35 mol % K2CO3; E 2: 710°C, 23 mol % KBO2, 43 mol % K2CO3, and 34 mol % K2MoO4; E 3: 710°C, 23 mol % KBO2, 43 mol % K2CO3, and 34 mol % K2WO4. The specific heats of melting of the eutectics were determined.  相似文献   

14.
马修臻  胡斌 《化学通报》2018,81(10):939-943,938
本文用高精度数字式振荡管密度计测定了288K至318K温度范围内Li2SO4 + Na2SO4 + H2O和 Li2SO4 + K2SO4 + H2O三元体系的密度。混合溶液的离子强度范围从0.1到4.5 mol.kg–1,混合溶液中Na2SO4和K2SO4的离子强度分数为0.2,0.4,0.6和0.8。用密度实验值拟合得到了不同温度下Pitzer离子相互作用模型混合参数θV和 ψV,模型的计算值与实验值的偏差在±0.002 g.cm3以内。用Pitzer模型计算了不同离子强度下三元体系的混合体积。  相似文献   

15.
Solubility in the Na2Cr2O7-(NH4)2Cr2O7-K2Cr2O7-H2O four-component water-salt system at 25, 50, and 75°C was studied for the first time. Phase field boundaries for individual salts and potassium and ammonium dichromate solid solutions, monovariant lines, and invariant points were determined. Experimental data were used to optimize the looped isohydric process of potassium dichromate preparation involving additional salts.  相似文献   

16.
The phase diagrams of the NaBO2-NaCl-Na2CO3, NaBO2-Na2CO3-Na2MoO4, NaBO2- Na2CO3-Na2WO4, and NaBO2-NaCl-Na2WO4 ternary systems were studied by a calculation-experimental method and differential thermal analysis. The coordinates of ternary eutectics were determined: E 1: 612°C, 16 mol % NaBO2, 42 mol % NaCl, and 42 mol % Na2CO3; E 2: 568°C, 12 mol % NaBO2, 28 mol % Na2CO3, and 60 mol % Na2MoO4; E 3: 575°C, 12 mol % NaBO2, 32 mol % Na2CO3, and 56 mol % Na2WO4; E 4: 628°C, 8 mol % NaBO2, 20 mol % NaCl, and 72 mol % Na2WO4; and E 5: 655°C, 9 mol % NaBO2, 53 mol % NaCl, and 38 mol % Na2WO4.  相似文献   

17.
Two compounds of formula La7A3W4O30 (with A=Nb and Ta) were prepared by solid-state reaction at 1450 and 1490 °C. They crystallize in the rhombohedric space group R-3 (No. 148), with the hexagonal parameters: , and , . The structure of the materials was analyzed from X-ray, neutron and electronic diffraction. These oxides are isostructural of the reduced molybdenum compound La7Mo7O30, which are formed of perovskite rod along [111]. An order between (Nb, Ta) and W is observed.  相似文献   

18.
The structural, electronic, and vibrational characteristics and energies of the isolated polyoxide clusters B20O30, Al20O30, V20O50, Si20O30H20, and Si20O30F20 and their complexes with the H ion and ammonia complexes Al20O30 · nNH3 have been calculated by the density functional theory B3LYP method with different basis sets. The computation results show that the symmetric closo structure I h with oxygen bridges located above the centers of the faces of an empty [M20] dodecahedron is more favorable for V20O50, Si20O30H20, and Si20O30F20. For B20O30, the cage closo isomer is also more favorable than the other isomers, but its structure is severely distorted as compared to a dodecahedron and has a symmetry close to C 3 . For Al20O30, the I h structure corresponds to a high-lying local minimum of the potential energy surface. For Al20O30, a set of unusual puckshaped isomers of symmetry C i , with different numbers of four-coordinate atoms IVAl and three-coordinate atoms IIIO, was localized; these structures are more than 90 kcal/mol more favorable than the dodecahedron I h . The most favorable isomer of Al20O30 contains twelve four-coordinate atoms IVAl and four five-coordinate atoms VAl. The energies of dissociation of the most favorable M20O30 clusters into the M2O3 (C 2v ) and M4O6 (T d ) fragments and, in the case of Al20O30, also into the Al8O12 (O h ) and Al12O18 (D 3d ) fragments, have been estimated. The conclusion has been drawn that these clusters can, in principle, exist and can be experimentally detected in the isolated state. Analogous calculations have been performed for ammonia complexes Al20O30 · nNH3 with n varying from 1 to 20. The effect of solvation on the relative stability of the dodecahedral and puckshaped isomers of the Al20O30 cluster is observed. The isomers with ammonia molecules in their first coordination sphere become much closer to one another on the energy scale; however, the dodecahedron remains a considerably less favorable intermediate. Original Russian Text ? O.P. Charkin, N.M. Klimenko, D.O. Charkin, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 4, pp. 624–635.  相似文献   

19.
Two compounds NaSr0.5Al2B2O7 and NaCa0.5Al2B2O7, have been found to crystallize into a new structure type by Rietveld refinement from X-ray powder diffraction data. Their structure belongs to hexagonal space group P63/m, with lattice parameters of , for NaSr0.5Al2B2O7 and , for NaCa0.5Al2B2O7, respectively. The structure is built up by [Al2B2O7]2− double layer and Na+/Ca2+ or Na+/Sr2+ ions alternatively stacking along the c-axis. The sites in the inter-double layer are fully occupied jointly by Na and Ca or Sr, but the intra-double layer sites are only half occupied solely by Na. A mechanism of the transition of the structure from CaAl2B2O7 to present structure type by replacing only 1% Ca by Na (2%) as observed by Chang and Keszler (Mater. Res. Bull. 33 (1998) 299) is also proposed.  相似文献   

20.
一些具有NASICON型网格结构的固体电解质具有高的电导率和好的稳定性,NASICON的意思是Na Super Ionic Conductor[1]。当NaZr2(PO4)3中P5 被Si4 部分取代时便可以得到具有NASICON结构的Na1 xZr2SixP3-xO12体系,其具有高的钠离子电导率。然而有相同结构的Li1 xZr2SixP3-xO12体系的离子电导率却很低,这是因为Li 半径太小,而NASICON三维网格结构的离子通道太大,两者不匹配而使电导率下降[2]。但当LiZr2(PO4)3中Zr4 被离子半径小些的Ti4 取代,所得LiTi2(PO4)3的通道就与Li 半径相匹配,适合于锂离子的迁移,从而使其电导率…  相似文献   

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