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1.
The bis(cyclopropylammonium)dihydrogenodiphosphate monohydrate is a new diphosphate associated with the organic molecule C3H5NH2. We report the chemical preparation and the crystal structure of this organic cation diphosphate. (C3H5NH3)2H2P2O7.H2O is orthorhombic (S.G. : P212121), with Z = 4 and the following unit-cell parameters : a = 4.828(1) Å, b = 11.011(1) Å, c = 25.645(2) Å. The P2O7 groups and H2O water molecules form a succession of bidimensional layers perpendicular to the c axis. The organic cations ensure the three-dimensional cohesion by NH-O hydrogen bonds.  相似文献   

2.
傅瑞标  吴新涛  胡胜民  王龙胜 《结构化学》2004,23(10):1107-1110
1 INTRODUCTION Metal organophosphonates have attracted considerable attention for over three decades due to their potential or practical applications, include- ing ion exchanges[1, 2], molecular sensors[3] and optics[4, 5]. Recently, a number of porous m…  相似文献   

3.
《Fluid Phase Equilibria》1999,165(2):157-168
A simple method is developed to estimate mixture critical temperatures (Tc), pressures (Pc), and densities (ρc) as a function of overall composition (X) from near critical region experimental coexistence data. This three-step method is applied to four mixtures, CO2–C3H8, CO2nC4H10, C2H6–C3H8, and C3H8nC4H10. Isothermal liquid–vapor coexistence data, which includes temperature, vapor pressure, coexisting densities (ρ and ρv), and coexisting compositions for the more volatile component (x1v and x1) are used. In the first step, the difference of the saturated liquid and vapor densities (ρρv) is fitted to an empirical function in ((PcP)/Pc) to obtain Pc. Then P/Pc and ((ρ+ρv)/2ρc) are simultaneously fitted to functions of a polynomial in (X1−(x1v+x1)/2) yielding estimates of ρc and X1. Finally, the discrete estimated critical data points are fitted with an equation to provide a continuous representation of the critical lines. The method is successfully tested for the mixtures, CO2–C3H8 and CO2nC4H10, for which there is a reasonable amount of isothermal data. The procedure is then applied to the mixtures, C2H6–C3H8 and C3H8nC4H10, for which there are sparse data. For all four mixtures, the critical temperature line, Tc vs. X1, matches literature values within ±0.5%. The critical pressure line, Pc vs. X1, and critical density line, ρc vs. X1, match literature values, in general, within ±2%.  相似文献   

4.
用从头计算法辅助以能量梯度法优化了反应C2H2^++H2→C2H3^++H的过渡态,用福井谦一的理论求出反应途径,用反应途径哈密顿理论及正则变分过渡态理论计算以应途径的动力学性质和反应速度数,在此基础上对涉及振动激发的选态反应速率常数进行计算,所得结果与现有的实验结果相符合。  相似文献   

5.
以三聚氰胺和硼酸为原料在水溶液中反应合成出了一种新的BCN化合物先驱体C3N6H6(H3BO3)2。XRD表征结果表明三聚氰胺和硼酸的最佳配比为1∶3(物质的量比)。用单晶X-射线衍射分析法测定了该化合物的晶体结构。该化合物属单斜晶系,空间群为P21/C,晶胞参数为a=0.3597(7)nm,b=2.0105(4)nm,c=1.4112(3)nm,α=90,°β=92.07(3),°γ=90,°V=1.0199(3)nm3,Z=4,D c=1.627g.cm-3,μ(MoKα)=0.144mm-1,F(000)=520。晶体结构经全矩阵最小二乘法修正,最终可靠因子R1=0.0519,wR2=0.1361。该化合物是由C3N6H6分子和H3BO3分子通过氢键加合组装形成的三维超分子结构化合物。  相似文献   

6.
标题配合物 [Cu(C8H4 F3O2 S) 2 (C12 H8N2 ) ]·C3H6 O属于三斜晶系 ,空间群为P1,并测得如下晶胞参数a =10 .5 77(3) ,b =15 .72 2 (4) ,c =10 .133(2 ) ,α =94 .5 3(2 ) ,β =10 0 .81(2 ) ,γ =96 .18(2 )° ,V =16 37.0 3 3,Z =2 ,Mr =74 4.18,Dx =1.5 1× 10 6 g·m- 3,F(0 0 0 ) =5 2 6 ,μ =8 2 4cm- 1,最终偏差因子为R =0 .0 83,Rw=0 .0 74。Cu(II)与 2个 4 ,4 ,4 三氟 1 (2 噻吩基 )丁二酮 1,3中的四个氧原子和菲咯啉中的两个氮原子 ,组成了一个畸变的八面体构型。  相似文献   

7.
OH+ C2H2N←C2H3 + NO→CH3 + NCO反应机理的密度泛函理论研究   总被引:1,自引:1,他引:1  
应用密度泛函理论研究了反应通道(a)C2H3 NO→CH3 NCO和(b)C2H3 NO→OH C2H2N的反应机理.在B3LYP/6-31G(d)水平上优化了反应物、中间体、过滤态、产物的几何构型,通过频率分析确定了11个中间体和10个过渡态.所有的反应物、中间体、过渡态、产物都在CCSD/6-311 G(d,P)水平上进行了单点能较正.并讨论了反应的异构化过程.计算结果表明10是能量最低的中间体,比反应物的能量低308.479kJ/mol;过渡态1/3,2/5,3/4,4/8比反应物的能量高,其中3/4是能量最高的过渡态,比反应物的能量高91.894kJ/mol.通道(a)和(b)的理论放热值分别为111.059和96.619kJ/mol.  相似文献   

8.
C2H3和NO2反应势能面的理论研究   总被引:2,自引:7,他引:2  
在CCSD(T)/6—311G(d,p)//B3LYP/6—3llG(d,p)水平上给出了反应C2H3 NO2的详细势能面信息,并列出了中间体和过渡态的几何构型.通过深入分析反应路径及反应机理,得到5个能量可行的产物和6条反应通道,其中产物C2H3O NO的形成又有利,而产物CH2CO HNO则是次要产物,其他产物在通常条件下可以忽略.  相似文献   

9.
C2H3+NO2反应速率常数的研究   总被引:6,自引:0,他引:6  
利用激光光解C2H3Br产生C2H3自由基,在气相298 K, 总压2.66×103 Pa的条件下,研究C2H3与NO2的反应,用激光光解-激光诱导荧光(LP-LIF)检测中间产物OH自由基的相对浓度随着反应时间的变化关系,报导了双分子反应C2H3+NO2的速率常数k(C2H3+NO2)=(1.8±0.05)×10-11cm3•molec.-1•s-1,同时也得到OH+NO2反应的速率常数k(OH+NO2)=(2.1±0.15)×10-12 cm3•molec.-1•s-1.  相似文献   

10.
本文测定了配合物3AgNO3·2BPrTE的晶体结构, 该晶体属三斜晶系, 空间各为PI,晶胞参数: a=0.8945(1), b=1.2355(2), c=1.3572(5)nm; α=98.69(2)°, β=92.74(2)°, γ=90.45(1)°; V=1.480nm^3; Z=2, 分子中三个Ag原子的配位数均为5, 但它们的配位多面体各不相同, Ag(3)为四方锥体, Ag(2)为三角双锥, Ag(1)则介于两者之间, NO3^-以单齿、不等长双齿和等长双齿两种形式配位于Ag原子。配体BPrTE也具有两种构象, 反式构象具有C1对称性, 并以两种形式和Ag原子配位, 偏转式构象不具有C4对称性, 与Ag原子形成五元螯合环, 分子为三维无限长链结构。  相似文献   

11.
Crystals of the copper bromide complexes with N-allylisoquinolinium halides of the composition [C9H7N(C3H5)]2CuIICl2.86Br1.14 (I), [C9H7N(C3H5)]CuIBr2 · H2O (II), and [C9H7N(C3H5)]CuIBr2 (III) are prepared by ac electrochemical synthesis, and their structures are studied by X-ray diffraction analysis (DARCh-1 (for I) and KUMA/CCD (for II and III) diffractometers). The crystals of compound I are monoclinic: space group P21/n, a = 15.053(5) Å, b = 10.486(4) Å, c = 17.179(10) Å, γ = 109.77(3)°, V = 2552(4) Å3, Z = 4. The crystals of complex II are triclinic: space group P $\overline 1 $ , a = 7.040(1) Å, b = 7.610(2) Å, c = 12.460(2) Å, α = 79.54(3)°, β = 86.73(3)°, γ = 89.51(1)°, V = 655.4(2) Å3, Z = 2. The crystals of complex III are monoclinic: space group P21/n, a = 12.799(1) Å, b = 7.692(1) Å, c = 13.491(1) Å, β = 111.08(1)°, V = 1239.3(2) Å3, Z = 4. The structure of compound I is built of the CuIIX 4 2? tetrahedra and N-allylisoquinolinium cations united by the C-H···X contacts into corrugated layers. The crystal structure of π-complex II is formed of dimers of the composition [C9H7(C3H5)]2 Cu 2 I Br4 forming layers in the direction of the z axis due to the C-H···X contacts. An important role in structure formation belongs to water molecules that cross-link the organometallic layers through the O-H···X contacts into a three-dimensional framework. When kept in the mother liquor for 6 months, the crystals of compound II transformed into crystals of compound III, whose structure consists of {[C9H7(C3H5)]2Cu 2 I Br4} n columns united through the C-H···Br contacts (H···Br 2.84(3)?2.92(4) Å) into a three-dimensional framework.  相似文献   

12.
合成了(Cu(C14H11o3)(C10H8N2)NO3.C2H5OH化合物并测定其晶体结构,晶体属P空间群,a=1.1911(2)nm,b=1.5322(2)nm,c=1.0492(2)nm,a=108.98(1)°β=107.04(1)°,γ=70.25(1)°Z=2.在(Cu(C14H11O3)(C10H8N2)2)配合阳离子中,2个2.2’-联吡啶的4个氮原子和二苯羟乙酸的1个羟基氧原子位  相似文献   

13.
Two organic–inorganic compounds based on Keggin building blocks have been synthesized by hydrothermal methods, (C7N2H7)3(C7N2H6)?·?PMo12O40?·?2H2O (1) and (C7N2H7)3(C7N2H6)2?·?AsMo12O40?·?3H2O (2) (C7N2H6?=?benzimidazole). Single-crystal X-ray analysis revealed that 1 crystallized in the triclinic system, P-1 space group with a?=?9.8980(4)?Å, b?=?11.2893(4)?Å, c?=?25.8933(9)?Å, α?=?93.307(2)°, β?=?90.630(2)°, γ?=?108.330(2)°, V?=?2740.68(18)?Å3, Z?=?2, R 1(F)?=?0.0740, ωR 2(F 2)?=?0.1511, and S?=?1.037; 2 crystallized in the triclinic system, P-1 space group with a?=?12.3353(4)?Å, b?=?13.2649(4)?Å, c?=?20.2878(6)?Å, α?=?95.6630(10)°, β?=?100.1720(10)°, γ?=?99.3940(10)°, V?=?3195.72(17)?Å3, Z?=?2, R 1(F)?= 0.0329, ωR2 (F 2)?=?0.1236, and S?=?1.088. The two compounds show a layer framework constructed from Keggin-polyoxoanion clusters and benzimidazole via hydrogen bonds and π–π stacking interactions, resulting in a 3-D supramolecular network. Both have high catalytic activity for oxidation of methanol. When the initial concentration of the methanol is 5.37?g?m?3 in air and the flow velocity is 4.51?mL?min?1, methanol is completely eliminated at 150°C for 1 (160°C for 2).  相似文献   

14.
The reaction of VO(acac)2 with 2-hydroxyl-1-naphthaldehyde isonicotinyl hydrazone and amines (ethylenediamine or diethylenetriamine) in CH3OH yields crystals of novel vanadium compounds characterized by IR, NMR spectroscopic methods and X-ray single-crystal structure determination. Two different vanadium units exist in the crystal cell of [VO2(C17H11N3O2)][VO- (C4H13N3)(C6H5N3O)](C2H5OH) which crystallizes in the triclinic system, space group P1 with a = 8.0104(17), b = 13.898(3), c = 14.955(3)A, α = 89.103(4), β = 79.551(4), γ = 78.352(4)°, V = 1603.3(6)A^3, Mr = 723.54, Dc = 1.499 g/cm^3, Z = 2, λ(MoKα) = 0.71073 ]A,μ= 0.644 mm^-1, F(000) = 748, the final R = 0.0547 and wR = 0.0997 for 8920 observed reflections with I 〉 2σ(I). According to structure analysis, two different molecules are arranged in the lattice and the two vanadium atoms adopt octahedral and square pyramidal coordination geometries, respectively. The interactions between DNA and vanadium complexes have been investigated by UV-Vis absorption spectro- photometry.  相似文献   

15.
The mechanism and kinetics of energy transfer from Xe(6s[3/2]1) resonance state (E=8.44 eV) to selected hydrocarbon molecules have been investigated by XeCl(B–X) (λmax=308 nm) fluorescence intensity measurements at stationary conditions in Xe–CCl4–M systems. Steady-state analysis of the fluorescence intensity dependence on the xenon and M pressure at constant CCl4 concentration shows that these process occur in the two- and three-body reactions: Xe(6s[3/2]10)+M→products, Xe(6s[3/2]10+M+Xe→products. The two- and three-body rate constants for these reactions have been found (see Table 1Table 1. Experimental parameters of Eq. (8)found by least square method in Xe–CCl4–C2H2 and Xe–CCl4–C2H4 systems for chosen xenon pressures in the range 25–150 Torr. Linear correlation coefficients (R) are also shown  相似文献   

16.
The product from reaction of samarium chloride hexahydrate with salicylic acid and Thioproline, [Sm(C7H5O3)2·(C4H6NO2S)]·2H2O, was synthesized and characterized by IR, elemental analysis, molar conductance, and thermogravimetric analysis. The standard molar enthalpies of solution of [SmCl3·6H2O(s)], [2C7H6O3(s)], [C4H7NO2S(s)] and [Sm(C7H5O3)2·(C4H7NO2S)·H2O(s)] in a mixed solvent of absolute ethyl alcohol, dimethyl sulfoxide(DMSO) and 3 mol L?1 HCl were determined by calorimetry to be Δs H m Φ [SmCl3 δ6H2O (s), 298.15 K]= ?46.68±0.15 kJ mol?1 Δs H m Φ [2C7H6O3 (s), 298.15 K]= 25.19±0.02 kJ mol?1, Δs H m Φ [C4H7NO2S (s), 298.15 K]=16.20±0.17 kJ mol?1 and Δs H m Φ [Sm(C7H5O3)2·(C4H6NO2S)]·2H2O (s), 298.15 K]= ?81.24±0.67 kJ mol?1. The enthalpy change of the reaction (1) $$ SmCl_3 \cdot 6H_2 O(s) + 2C_7 H_6 O_3 (s) + C_4 H_7 NO_2 S(s) = Sm(C_7 H_5 O_3 )_2 \cdot (C_4 H_6 NO_2 S) \cdot 2H_2 O(s) + 3HCl(g) + 4H_2 O(1) $$ was determined to be Δs H m Φ =123.45±0.71 kJ mol?1. From date in the literature, through Hess’ law, the standard molar enthalpy of formation of Sm(C7H5O3)2(C4H6NO2S)δ2H2O(s) was estimated to be Δs H m Φ [Sm(C7H5O3)2·(C4H6NO2S)]·2H2O(s), 298.15 K]= ?2912.03±3.10 kJ mol?1.  相似文献   

17.
The syntheses and crystal structures of the closely related but non-isostructural Cd2(C19H21N3O3F)4(H2O)2?·?4H2O (1) and Pb2(C19H21N3O3F)4?·?4H2O (2) are described, where C19H21N3O3F? is enrofloxacinate (enro). Both compounds contain centrosymmetric, binuclear, neutral complexes incorporating a central diamond-shaped M2O2 (M?=?Cd, Pb) structural unit. The Cd2+ coordination polyhedron in 1 is a CdO6 trigonal prism, including one coordinated water. The Pb2+ coordination polyhedron in 2 can be described as a very distorted square-based PbO5 pyramid, although two additional short Pb?···?O (<3.1?Å) contacts are also present. In the crystal of the cadmium complex, O–H?···?O hydrogen bonds lead to a layered structure. In the lead compound, O–H?···?O and O–H?···?N interactions lead to chains in the crystal. Crystal data: 1: C76H96Cd2F4N12O18, M r?=?1766.45, triclinic, P 1, a?=?12.185(2)?Å, b?=?12.306(3)?Å, c?=?14.826(3)?Å, α?=?68.15(3)°, β?=?70.28(3)°, γ?=?86.11(3)°, V?=?1938.2(7)?Å3, Z?=?1, T?=?298 K, R(F)?=?0.030, wR(F 2)?=?0.079. 2: C76H88F4N12O16Pb2, M r?=?1920.00, triclinic, P 1, a?=?12.0283(4)?Å, b?=?12.7465(4)?Å, c?=?13.0585(4)?Å, α?=?83.751(1)°, β?=?74.635(1)°, γ?=?81.502(1)°, V?=?1904.3(1)?Å3, Z?=?1, T?=?298?K, R(F)?=?0.021, wR(F 2)?=?0.049.  相似文献   

18.
王嘉  尤瑞  千坤  潘洋  杨玖重  黄伟新 《催化学报》2021,42(12):2242-2253
以烯烃为还原剂的NOx选择性催化还原(HC-SCR)是重要的环境催化反应之一.Ag/Al2O3催化剂(SA)因在HC-SCR反应中表现高活性、高N2选择性及中等H2O和SO2耐受性等优点,而被广泛研究.SA催化剂中存在不同的Ag物种,包括孤立Ag+离子,带部分正电荷Agnδ+团簇和金属态Agn0团簇.文献研究结果表明,SA催化剂中Agnδ+团簇是催化HC-SCR反应的活性Ag物种,而Ag物种类型与Ag的负载量密切相关.因此文献中研究SA催化HC-SCR反应的结构-性能关系主要是通过改变Ag负载量来开展的,最优Ag负载量约为1%~2%.本文以Cl–改性的γ-Al2O3作为载体,采用传统的浸渍法制备了Ag/Al2O3-Cl催化剂(SA-Cl),通过XRD、TEM、H2-TPR、UV-Vis DRS以及XPS对催化剂进行了结构表征,并结合C3H6-SCR和H2/C3H6-SCR活性测试,建立催化剂结构-催化性能关系;同时利用原位傅里叶变换红外光谱(DRIFTS)和在线同步辐射单光子电离质谱(SVUV-PIMS)研究了SA催化HC-SCR的反应机理.结构表征结果表明,在SA催化剂中,Ag负载量的提高主要是增加了Agn0物种,而在SA-Cl催化剂中,Ag负载量的提高主要是增加了Agnδ+物种,因此Cl?改性能促进SA催化剂中Agnδ+物种的形成.活性测试结果表明,在相同Ag负载量下,SA-Cl催化剂表现出比SA催化剂更好的HC-SCR催化性能.Cl?改性对SA催化剂中Ag物种的调控作用和HC-SCR催化性能的促进作用随Ag负载量的增加变得更为明显.原位DRIFTS结果表明,γ-Al2O3载体(Al位点)是NO氧化形成硝酸盐物种的主要活性位点;Agnδ+物种催化丙烯适度氧化主要生成乙酸盐类物种,可以还原表面硝酸盐物种;而Agn0催化丙烯过度氧化主要生成羧酸盐类物种,进而生成CO2,不能还原表面硝酸盐物种.由此可见,Agnδ+是催化HC-SCR反应的活性Ag物种,而Agn0是催化烃类完全氧化反应的活性Ag物种;Cl–改性能有效促进Agnδ+的形成,进而提高HC-SCR催化反应活性.在线SVUV-PIMS结果检测到H2/C3H6-SCR反应中存在气态中间物种丙烯腈(CH2=CHCN).–CN和–NCO物种被认为是HC-SCR反应的关键中间物种,能够直接与气相NO+O2反应生成N2.因此,CH2=CHCN的存在说明HC-SCR反应涉及到气相反应机理.基于SA和SA-Cl催化剂,进一步研究了H2对C3H6-SCR低温活性的促进作用.结果表明,H2的促进作用是通过作用于Agnδ+物种,而不是通过Agn0物种来实现的;H2的引入有利于低温下强吸附硝酸盐物种的脱附或分解以及中间体向–NCO和–CN物种的转化,从而提高HC-SCR低温催化活性.综上,基于Cl–改性的Ag/Al2O3-Cl催化剂,本文成功证实了Agnδ+物种是催化HC-SCR反应的活性Ag物种,并结合原位DRIFTS在线SVUV-PIMS谱分别鉴定了催化反应表面中间物种和气相中间物种.这些结果加深了对SA催化HC-SCR反应构-效关系和反应机理的基础理解.  相似文献   

19.
Reactions of a solution of AgNO3 in aqueous methanol with solutions of 1,4-diallylpiperazine (acidified with HNO3 to pH = 4) and 1-allyloxybenzotriazole in ethanol gave the crystalline silver(I) π-complexes [Ag2(C4H8N2(C3H5)2(H+)2)(H2O)2(NO3)2](NO3)2 (I) and [Ag(C6H4N3(OC3H5)(NO3))] (II). Their crystal structures were determined by X-ray diffraction. Crystals of complexes I and II are monoclinic, space group P21/c; for I: a = 7.053(3)Å, b = 9.389(3)Å, c = 15.488(4)Å, β = 91.60°, V = 1025.3(6)Å3, Z = 4; for II: a = 10.650(4)Å, b = 15.062(5)Å, c = 7.412(4)Å, β = 104.20(3)°, V = 1152.6(8)Å3, Z = 4. In both structures, the organic components act as bidentate ligands forming with AgNO3 34- and 14-membered topological rings, respectively. In complex I, the nearly tetrahedral environment of the Ag(I) atom is made up of the olefinic C=C bond, the O atoms of the nitrate anions, and the water molecule. 1-Allyloxybenzotriazole in structure II causes the deformation of the coordination polyhedron of Ag into a trigonal pyramid via inclusion of the ligand N atom in its coordination sphere. The topological units of the complexes form infinite polymer layers linked by anionic NO 3 ? bridges. In structure I, these layers are united through a system of hydrogen bonds into a three-dimensional framework.  相似文献   

20.
The solubility of components in the system Mg(ClO3)2-2NH2C2H4OH · H3C6H5O7-H2O was studied from the complete freezing temperature ?59.4°C to 20.0°C. A polythermal solubility diagram was constructed, in which the crystallization fields were determined for ice, Mg(ClO3)2 · 16H2O, Mg(ClO3)2 · 12H2O, Mg(ClO3)2 · 6H2O, 2NH2C2H4OH · H3C6H5O7 · H2O, 2NH2C2H4OH · H3C6H5O7, and two new compounds, [(HOC(CH2COOH)2COO)2Mg · 2H2O] and [HOC(CH2COO)2MgCOOH · 2H2O], which were identified by chemical and physicochemical analysis methods.  相似文献   

P(Xe) (Torr)C2H4C2H2
Empty Cellab×1016 cm3/molec.Rab×1016 cm3/molec.R
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