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1.
Journal of Structural Chemistry - New complex salts [Pd(NH3)4][Pd(NH3)3NO2][CrOx3]·H2O I, [Pd(NH3)4][Pd(NH3)3NO2][CoOx3]·H2O II, and a series of solid solutions...  相似文献   

2.
The structure of double complex salts [Pd(NH3)3(NO2)][Rh(NH3)2(NO2)4] and [PdEn2][Rh(NH3)(NO2)5]·0.75H2O is determined by single crystal X-ray diffraction. In the structures, the main structural moieties are identified.  相似文献   

3.
本文首次报道须在两种金属离子同时作用下的振荡反应——KBrO_3-CH_3CH(NH_2)CO_2H-MnSO_4-[Fe(phen)_3]SO_2-H_2SO_4体系的振荡反应,对反应产物作了分析,研究了两种金属离子在振荡反应中的不同作用,Mn~(2+)起催化氧化丙氨酸以产生丙酮酸的作用,而[Fe(phen)_3]~(2+)则是丙酮酸-BZ型反应的催化剂.研究了温度变化对振荡反应的影响,从而得出振荡反应各阶段的表观活化能.考察了Cl~-、自由基抑制剂及反应物浓度对振荡反应的影响.实验证明,振荡反应同时受Br~-及Br_2的控制,振荡机理与Br_2-水解控制模型相同.  相似文献   

4.
本文首次报道须在两种金属离子同时作用下的振荡反应─KBrO3-CH3CH(NH2)CO2H-MnSO4-[F3(phen)3]SO4-H2SO4体系的振荡反应, 对反应产物作了分析, 研究了两种金属离子在振荡反应中的不同作用, Mn^2^+起催化氧化丙氨酸以产生丙酮酸的作用, 而[Fe(phen)3]^2^+则是丙酮酸-BZ型反应的催化剂。研究了温度变化对振荡反应的影响, 从而得出振荡反应各阶段的有观活化能。考察了Cl^-、自由基抑制剂及反应物浓度对振荡反应的影响。实验证明, 振荡反应同时受Br^-及Br2的控制, 振荡机理与Br2^-水解控制模型相同。  相似文献   

5.
Compounds [Rh(NH3)5(NO2)](NO3)2·H2O (I) with a = 7.6230(3) Å, b = 7.6230(3) Å, c = 10.3584(4) Å, space group I-42m, Z = 2, d calc = 2.026 g/cm3, V = 601.93(4) Å3, Rh-NH3 eq = 2.074 Å, Rh-NH3 ax (NO2) = 2.048 Å; [Rh(NH3)5(NO2)][Pd(NO2)4] (II) with a = 8.095(3) Å, b = 22.422(8) Å, c = 7.887(3) Å, β = 98.559(17)°, space group Cc, Z = 4, d calc = 2.461 g/cm3, V = 1415.6(9) Å3, Rh-NH3 eq = 2.069 Å, Rh-NH3 ax = 2.090 Å, Rh-NO2 = 2.002 Å; K2[Rh(NH3)(NO2)5]·H2O (III) with a = 7.5177(5) Å, b = 20.9856(15) Å, c = 7.7017(5) Å, space group Cmc21, Z = 4, d calc = 2.439 g/cm3, V = 1215.05(14) Å3, Rh-NH3 ax (NO2) = 2.094 Å, Rh-NO2 eq = 2.030 Å are synthesized and studied using single crystal X-ray diffraction.  相似文献   

6.
Crystal structures of [Co(MH)2(Thio)2][BF4] · H2O (I) and [Co(DH)2(NH3)2][BF4] (II), where MH is H3C–C(NOH)–C(NO)–H and DH is H3C–C(NOH)–C(NO)–CH3, were determined by X-ray diffraction. The crystals are monoclinic, space group C2/c, unit cell parameters (for I and II, respectively): a = 22.018(2) Å, b = 7.943(1) Å, c = 11.681(1) Å, = 92.68(1)° and a = 21.436(2) Å, b = 6.400(2) Å, c = 12.389(2) Å, = 113.13(1)°. In both cases, the Co(III) coordination polyhedron is a centrosymmetrical trans-octahedron, N4S2 for I and N6 for II. In the crystals of I and II, the complex cations and the outer-sphere [BF4] anions (and the crystal water molecules in I) form elaborate hydrogen bonding system.  相似文献   

7.
The i.r. and Raman spectra of room temperature phase (phase II) of (NH4)3H(SO4)2 and (ND4)3D(SO4)2 as polycrystalline samples and single crystals have been investigated between 4000 and 30 cm−1. An assignment of internal and external modes is given in terms of group frequencies and symmetry types. This crystal contains non-centrosymmetric dimers (SO4HSO4)3− where sulphate ions are associated by strong asymmetric OH … O hydrogen bonds; they are characterized by two strong Raman bands at 1078 and 966 cm−1, and a νOH frequency at about 1250 cm−1. The acidic proton is statistically disordered around the crystallographic symmetry centre while all of the NH+4 ions show an important dynamical orientational disorder.  相似文献   

8.
《Chemical physics letters》2002,350(5-6):650-655
The dissociative photodetachment dynamics of (SO2)3 were studied by photoelectron–photofragment coincidence spectroscopy at 258 nm. Correlation between the photoelectron and photofragment translational energies was observed as previously seen in the dimer system, implying the presence of a dimer core. The three-body dissociation dynamics of (SO2)3 after photodetachment are consistent with a dimer core solvated by a spectator SO2 molecule with a broad distribution in initial geometry.  相似文献   

9.
A single crystal X-ray diffraction study of Na3[Rh(SO3)3(NH3)3]·6H2O was carried out (X8 APEX BRUKER automated diffractometer, MoK α radiation, graphite monochromator); crystal data are a = 10.1844(1) Å, c = 64.0815(13) Å, V = 5756.17(14) Å3, space group R $\bar 3$ c, Z = 12. The general motif of the structure was analyzed in terms of the mutual spatial arrangement of the [(NH3)3Rh(SO3)3-Na-(SO3)3Rh(NH3)3]5? fragments, where the Na+ cation is surrounded by six oxygen atoms belonging to six SO3 groups. This cation resides on the inversion center, all Na-O distances are identical, 2.347 Å. The selected fragments follow the nodes of a rhombohedral sublattice (a c = 12.19 Å, αc = 49.38°) formed by the intersection of three symmetry-related families of planes (1 0 2).  相似文献   

10.
硫助金属氧化物(sulfate promoted metal oxides)是一类新型固体酸催化剂,可用于多种酸催化反应.用(NH_4)_2SO_4、SO_3、SO_2或H_2S 作为助剂,以Fe_2O_3、TiO_2和ZrO_2为底物均可制得硫助金属氧化物(SPMO).  相似文献   

11.
Monohydrates of chloropentammine rhodium(III) and chloropentammine cobalt(III) tetracloropalladates(II) were synthesized. Single crystals of [Rh(NH3)5Cl][PdCl4] · H2O were obtained and studied by Xray diffraction. The crystallographic data are as follows: a = 7.8730(16) Å, b = 10.905(2) Å, c = 16.038(3) Å, = 102.70(3)°, V = 1343.3(5) Å3, space group P21/c, Z = 4, dcalc = 2.422 g/cm3. The structure consists of alternating layers of [Rh(NH3)5Cl]2+ complex cations and [PdCl4]2- complex anions. Each anion layer contains two crystallographically independent Pd atoms, and the square coordination environment of one of these atoms is converted to a bipyramide. The structure of the compound [Co(NH3)5Cl][PdCl4] · H2O is determined and its unitcell parameters are refined: a = 7.813(3) , b = 10.896(4) , c = 15.966(5) , = 102.85(4)°, V = 1325.2(8) 3, and dcalc = 2.148 g/cm3. The synthesis temperature is shown to have an effect on the content of hydrated and anhydrous complexes in the mixture formed during precipitation of these binary salts from aqueous solutions.  相似文献   

12.
In the presence of ethylenediamine template agents, a metal(II) phosphonate, [NH3CH2CH2NH3][Fe2(O3PCH(OH)CO2)2(H2O)2]?·?2H2O (1) has been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction as well as infrared spectroscopy, elemental analysis and thermogravimetric analysis. The compound crystallines in the monoclinic space group P21/n: Crystal data for 1: a?=?8.4523(8)?Å, b?=?9.8196(9)?Å, c?=?10.9217(10)?Å, β?=?105.9500(10)°, V?=?871.58(14)?Å, Z?=?2, D c?=?2.103?g?cm?3, R 1?=?0.0290, wR 2?=?0.0811. The Fe (II) cation is octahedrally coordinated by six oxygen atoms from the three ligands and one coordinated water molecule to form a 2D layered structure with a one-dimensional channel system in the a-axis direction.  相似文献   

13.
Stability of (NH4)2SO4 · H2O2 aqueous solutions and some structural changes in ammonium sulfate in the course of its solvation and subsequent desolvation were studied.  相似文献   

14.
Russian Journal of Coordination Chemistry - The formation of complex salt [Ag(PPh3)4][2-B10H9NH3 ? 2DMF] (I) by the reaction of the salts of the [2-B10H9NH3]– anion with [Ag(PPh3)4]NO3...  相似文献   

15.
无机-有机杂化钒氧酸盐由于其结构的多样性以及在催化、医药、光、电、磁等材料领域中的应用前景而受到人们的广泛关注。近年来这一研究领域的重大进步是将有机氮配体或者过渡金属配合物直接连接到矾氧骨架上以获得各种新奇结构。合成出许多属于L/V/O、MXLY/V/O、L/P/V/O和MXLY  相似文献   

16.
The synthesis and crystal structures of [H3NCH2CH2NH3][V2O6] (1) and [HN(CH2CH2)3NH][VV 2VIV 4O14]·H2O (2) are described. The structure of the oxidized compound 1 consists of parallel stacks of vanadium oxide chains of corner sharing {VO4} tetrahedra. The chains are stabilized by extensive hydrogen bonding involving oxide ligands of the chains and ethylenediammonium ions which fill the space between the stacks of chains. The structure of compound 2 consists of vanadium oxide layers separated by doubly protonated 1,4-diazabicyclo[2.2.2]octane and lattice water. The vanadium oxide layers, containing mixed-valence vanadium (VV and VIV) centers, are composed of zigzag ribbons of edge-sharing {VO5} square pyramids interconnected by {VO4} tetrahedra. Crystal data. C2H10N2O6V2 , 1: monoclinic, space group P21/c (No. 14), a=5.5359(5), b=12.9430(12), c=5.6856(5) Å, =90, =97.460(2), =90°, V=403.93(6) Å3, Z=2. A total of 2506 reflections ( max=27.89°) was collected, of which 954 were used to resolve the structure. The structure was solved by direct methods and least-squares refinement converged at R=0.0592. C6H16N2O15V6, 2: monoclinic, space group C2 (No. 5), a=19.303(4), b=6.667(2), c=7.579(2) Å, =90, =111.31(2), =90°, V=908.4(4) Å3, Z=2. A total of 1779 reflections was collected, of which 1591 unique reflections were used for structural elucidation. The structure was solved by direct methods and least-squares refinement converged at R=0.0314.  相似文献   

17.
Equilibrium solubility curves of the ammonium aluminium sulphate in aqueous solutions of sulphuric acid have been calculated using checked literature data and our own measurements. The concentration of sulphuric acid ranged from 0 to 23 mass%, temperature range between 20 and 60°C has been extrapolated up to 75°C by means of a thermodynamically based correlation method. The solubility correlation as well as the hydration analysis implied a possible destructuralization of solutions at higher acid concentrations. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

18.
The first fluorosulfonic ultraviolet (UV) nonlinear optical (NLO) material, C(NH2)3SO3F, is rationally designed by taking KBe2BO3F2 (KBBF) as the parent compound. C(NH2)3SO3F features similar topological layers as KBBF by replacing inorganic (BO3)3− with organic C(NH2)3+ trigonal units and BeO3F with SO3F tetrahedra. Therefore, C(NH2)3SO3F is a metal-free UV NLO crystal. Benefiting from the coplanar configuration of the C(NH2)3+ cationic groups, it possesses a large SHG response of 5×KDP and moderate birefringence of 0.133@1064 nm. Besides, it has a short UV cutoff edge of 200 nm. The calculated results reveal the shortest SHG phase-matching wavelengths can reach 200 nm. These findings highlight the exploration of metal-free compounds as nontoxic and low-cost UV NLO materials as a new research area.  相似文献   

19.
Ternary clusters (NH3)·(H2SO4)·(H2O)n have been widely studied. However, the structures and binding energies of relatively larger cluster (n > 6) remain unclear, which hinders the study of other interesting properties. Ternary clusters of (NH3)·(H2SO4)·(H2O)n, n = 0-14, were investigated using MD simulations and quantum chemical calculations. For n = 1, a proton was transferred from H2SO4 to NH3. For n = 10, both protons of H2SO4 were transferred to NH3 and H2O, respectively. The NH4+ and HSO4 formed a contact ion-pair [NH4+-HSO4] for n = 1-6 and a solvent separated ion-pair [NH4+-H2O-HSO4] for n = 7-9. Therefore, we observed two obvious transitions from neutral to single protonation (from H2SO4 to NH3) to double protonation (from H2SO4 to NH3 and H2O) with increasing n. In general, the structures with single protonation and solvated ion-pair were higher in entropy than those with double protonation and contact ion-pair of single protonation and were thus preferred at higher temperature. As a result, the inversion between single and double protonated clusters was postponed until n = 12 according to the average binding Gibbs free energy at the normal condition. These results can serve as a good start point for studies of the other properties of these clusters and as a model for the solvation of the [H2SO4-NH3] complex in bulk water.  相似文献   

20.
Min Zhang 《合成通讯》2013,43(7):835-841
An efficient synthesis of 3,4‐dihydropyrimidin‐2(1H)‐ones (DHPMS) from aromatic aldehydes, β‐keto ester, and urea (or thiourea) in refluxing ethanol using zinc sulfamate as a catalyst is first described here. Compared to the classical Biginelli reaction, this new method consistently has the advantages of good yields (76–96%), short reaction time (2–5 h), no corrosion of equipment, ease of manipulation, and low‐cost catalyst.  相似文献   

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