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1.
On Chalcogenolates. 164. Reactions of Hydrazine with Carbon Disulfide. 3. Synthesis and Characterization of Trisodium 1,2-Hydrazine-bis(dithiocarboxylate) The mixed dithiocarbamate-dithiocarbimate Na3[S2C? NH? N°CS2] · 7 H2O has been prepared by reaction of H2N? NH2 · H2O with CS2 and NaOH in aqueous solution. It has been characterized by means of diverse methods.  相似文献   

2.
Modified Synthesis and Crystal Structure Determination of β-Na2CS3 . β-Na2CS3 has been synthesized via a novel route from Na2S and CS2, and its crystal structure has been determined using single crystal techniques (for crystallographic informations see “Inhaltsübersicht”). Structural relations between Li2CO3 and β-Na2CS3 are discussed. The ionic conductivities are 3 · 10?11S cm?1 and 1.3 · 10?2S cm?1 at 50°C and 250°C, respectively.  相似文献   

3.
DFT investigations are carried out to explore the effective catalyst forms of DBU and H2O and the mechanism for the formation of 2,3‐dihydropyrido[2,3‐d]‐pyrimidin‐4(1H)‐ones. Three main pathways are disclosed under unassisted, water‐catalyzed, DBU and water cocatalyzed conditions, which involves concerted nucleophilic addition and H‐transfer, concerted intramolecular cyclization and H‐transfer, and Dimroth rearrangement to form the product. The results indicated that the DBU and water cocatalyzed pathway is the most favored one as compared to the rest two pathways. The water donates one H to DBU and accepts H from 2‐amino‐nicotinonitrile ( 1 ), forming [DBU‐H]+‐H2O as effective catalyst form in the proton migration transition state rather than [DBU‐H]+‐OH?. The hydrogen bond between [DBU‐H]+···H2O··· 1 ? decreases the activation barrier of the rate‐determining step. Our calculated results open a new insight for the green catalyst model of DBU‐H2O. © 2015 Wiley Periodicals, Inc.  相似文献   

4.
Concerning Sodium Arsenites in the Three Component System Na2O? As2O3? H2O at 6°C Four phases Na2(H2As4O8) 1c , NaAsO2 · 4 H2O 2c , Na2(HAsO3) · 5 H2O 3c , and Na5(HAsO3)(AsO3) · 12 H2O 4c have been identified in the system Na2O? As2O3? H2O at 6°C and characterized by X-ray structural analysis. Polymetaarsenite anions, adopt in 1c and 2c , respectively, octet or doublet single chains.  相似文献   

5.
On the Chemistry of Bauxite Extraction. II. Studies in the System Na2O? CaO? Al2O3? TiO2? H2O between 100 and 275°C The formation of crystalline compounds in the system Na2O? CaO? Al2O3? TiO2? H2O was studied between 100 and 275°C. With caustic alkali concentrations up to 300 g Na2O/l the calcium aluminate 3 CaO · Al2O3 · 6 H2O is formed. With rising temperatures two different calcium titanates, among them perovskite, CaTiO3, are identified. Above 200°C perovskite is formed at all concentrations investigated.  相似文献   

6.
Three complexes, Na4[DyIII(dtpa)(H2O)]2?·?16H2O, Na[DyIII(edta)(H2O)3]?·?3.25H2O and Na3[DyIII (nta)2(H2O)]?·?5.5H2O, have been synthesized in aqueous solution and characterized by FT–IR, elemental analyses, TG–DTA and single-crystal X-ray diffraction. Na4[DyIII(dtpa)(H2O)]2?·?16H2O crystallizes in the monoclinic system with P21/n space group, a?=?18.158(10)?Å, b?=?14.968(9)?Å, c?=?20.769(12)?Å, β?=?108.552(9)°, V?=?5351(5)?Å3, Z?=?4, M?=?1517.87?g?mol?1, D c?=?1.879?g?cm?3, μ?=?2.914?mm?1, F(000)?=?3032, and its structure is refined to R 1(F)?=?0.0500 for 9384 observed reflections [I?>?2σ(I)]. Na[DyIII(edta)(H2O)3]?·?3.25H2O crystallizes in the orthorhombic system with Fdd2 space group, a?=?19.338(7)?Å, b?=?35.378(13)?Å, c?=?12.137(5)?Å, β?=?90°, V?=?8303(5)?Å3, Z?=?16, M?=?586.31?g?mol?1, D c?=?1.876?g?cm?3, μ?=?3.690?mm?1, F(000)?=?4632, and its structure is refined to R 1(F)?=?0.0307 for 4027 observed reflections [I?>?2σ(I)]. Na3[DyIII(nta)2(H2O)]?·?5.5H2O crystallizes in the orthorhombic system with Pccn space group, a?=?15.964(12)?Å, b?=?19.665(15)?Å, c?=?14.552(11)?Å, β?=?90°, V?=?4568(6)?Å3, Z?=?8, M?=?724.81?g?mol?1, D c?=?2.102?g?cm?3, μ?=?3.422?mm?1, F(000)?=?2848, and its structure is refined to R 1(F)?=?0.0449 for 4033 observed reflections [I?>?2?σ(I)]. The coordination polyhedra are tricapped trigonal prism for Na4[DyIII(dtpa)(H2O)]2?·?16H2O and Na3[DyIII(nta)2(H2O)]?·?5.5H2O, but monocapped square antiprism for Na[DyIII(edta)(H2O)3]?·?3.25H2O. The crystal structures of these three complexes are completely different from one another. The three-dimensional geometries of three polymers are 3-D layer-shaped structure for Na4[DyIII(dtpa)(H2O)]2?·?16H2O, 1-D zigzag type structure for Na[DyIII(edta)(H2O)3]?·?3.25H2O and a 2-D parallelogram for Na3[DyIII(nta)2(H2O)]?·?5.5H2O. According to thermal analyses, the collapsing temperatures are 356°C for Na4[DyIII(dtpa)(H2O)]2?·?16H2O, 371°C for Na[DyIII(edta)(H2O)3]?·?3.25H2O and 387°C for Na3[DyIII(nta)2(H2O)]?·?5.5H2O, which indicates that their crystal structures are very stable.  相似文献   

7.
The Crystal Structure of the Sodium Oxohydroxoaluminate Hydrate Na2[Al2O3(OH)2] · 1.5 H2O The crystal structure of the sodium oxohydroxoaluminate hydrate Na2[Al2O3(OH)2] ·s 1.5 H2O (up to now described as Na2O · Al2O3 · 2.5 H2O and Na2O · Al2O3 · 3 H2O, respectively) was solved. The X-ray single crystal diffraction analysis (tetragonal, space group P-421m, a = 10.522(1) Å, c = 5.330(1) Å, Z = 4) results in a polymeric layered structure, consisting of AlO3/2(OH) tetrahedral groups. Between these layers the Na+ ions are situated, which form tetrameric groups of face-linked NaO6 octahedra. The involved O2? ions are due to Al? O? Al bridges, Al? OH groups and water of crystallization. 27Al and 23Na MAS NMR investigations confirm the crystal structure analysis. The relations between the crystallization behaviour of the compound and the constitution of the aluminate anions in the corresponding sodium aluminate solution and in the solid, respectively, are discussed.  相似文献   

8.
Two new coordination supramolecular complexes based on a versatile and unsymmetrical 5-(4-pyridyl)-1,3,4-oxadiazole-2-thione (Hpot) and MnII and NiII have been synthesized and structurally characterized by single-crystal X-ray diffraction analysis. Reaction of MnCl2?· 4H2O with Hpot afforded a neutral mononuclear complex [Mn(pot)2(H2O)4]?·?2H2O (1), which exhibits a three-dimensional (3-D) supramolecule through versatile intermolecular O–H?···?X (X=O, N and S) hydrogen bond interactions. When using NiCl2?·?6H2O instead of MnCl2?· 4H2O under similar reaction conditions, a neutral mononuclear complex [Ni(pot)2(H2O)4] (2) is also obtained, which does not exhibit intermolecular hydrogen bonds and π–π stacking interactions. It is very interesting that the pot anion exhibits different coordination modes in complexes 1 and 2. The IR spectra and the TGA for 1 and 2 have been investigated and discussed in detail.  相似文献   

9.
Nonasodium Bis(hexahydroxoaluminate) Trihydroxide Hexahydrate (Na9[Al(OH)6]2(OH)3 · 6H2O) – Crystal Structure, NMR Spectroscopy and Thermal Behaviour The crystal structure of the nonasodium bis(hexahydroxoaluminate) trihydroxide hexahydrate Na9[Al(OH)6]2(OH)3 · 6H2O (4.5 Na2O Al2O3 · 13.5 H2O) (up to now described as 3 Na2O · Al2O3 · 6H2O, 4Na2O · Al2O3 · 13 H2O and [3 Na2O · Al2O3 · 6H2O] [xNaOH · yH2O], respectively) was solved. The X-ray single crystal diffraction analysis (triclinic, space group P1 , a = 8.694(1) Å, b = 11.344(2) Å, c = 11.636(3) Å, α = 74.29(2)°, β = 87.43(2)°, γ = 70.66(2)°, Z = 2) results in a structure, consisting of monomeric [Al(OH)6]3? aluminate anions, which are connected by NaO6 octahedra groups. Furthermore the structure contains both, two hydroxide anions only surrounded by water of crystallization and OH groups of [Al(OH)6]3? aluminate anions and a hydroxide anion involved in three NaO6 coordination octahedra directly and moreover connected with a water molecule by hydrogen bonding. The results of 27Al and 23Na-MAS-NMR investigations, the thermal behaviour of the compound and possible relations between the crystal structure and the conditions of coordination in the corresponding sodium aluminate solution are discussed as well.  相似文献   

10.
On the Crystalline Phases of the Systems M O? Al2O3? H2O (MI = K, Na) In the system K2O? Al2O3? H2O the compounds K2O · Al2O3 · 3 H2O, K2O · Al2O3 · 2 H2O and K2O · Al2O3 · 1 H2O exist. The results of 27Al and 1H NMR and IR spectroscopic investigations as well as thermoanalytical measurements confirm the existence of dimeric anions with tetrahedrally coordinated Al for the 3-hydrate. In the case of the two other hydrates higher molecular anions occur, also formed by AlO4 tetrahedra. In the system Na2O? Al2O3? H2O a compound with a composition Na2O · Al2O3 · 2,5 H2O and two alkali oxide rich phases (Na/Al > 3) are observed. In monosodium aluminate hydrate there are highly polymerized anions with tetrahedrally coordinated Al, whereas the alkali oxide rich phases are probably built up by monomeric [Al(OH)6]3? anions.  相似文献   

11.
Two new ZnII complexes, {[Zn(L)(phen)(H2O)]?·?H2O} (1) and {[Zn(L)(4bpy)(H2O)]?·?H2O} (2) (L?=?5,6-dihydro-1,4-dithiin-2,3-dicarboxylate, phen?=?1,10-phenanthroline, and 4bpy?=?4,4′-bipyridine), have been prepared by in situ reaction of Zn(ClO4)2?·?6H2O with 5,6-dihydro-1,4-dithiin-2,3-dicarboxylic anhydrate in the presence of lithium hydroxide, together with incorporating chelating phen or bridging 4bpy as co-ligands. Their structures were determined by single-crystal X-ray diffraction. Complex 1 takes a 1-D helical structure that is further assembled into a 2-D network by O–H?···?O, C–H?···?O hydrogen bonds, and weak S?···?S interactions, and then an overall 3-D supramolecular framework was formed by π?···?π stacking interactions. Complex 2 possesses a 2-D (4,4)-layered structure. The structural difference between 1 and 2 can be attributed to the different N-donor auxiliary co-ligands. Both 1 and 2 are photoluminescent materials whose emission properties are closely related to their intrinsic structure.  相似文献   

12.
The reaction of Co(NO3)2?·?6H2O with a tripodal ligand leads to a new complex {[Co(L)]?·?2NO3?·?8H2O} (1) confirmed by single-crystal X-ray diffraction, infrared spectroscopy, and elemental analysis. The particular interest of 1 is in the formation of a 1-D water tape consisting of (H2O)16 cluster units, the neighboring water tapes are connected by free nitrate anions via hydrogen bonds into a 2-D guest layer. These guest layers are alternately packed face-to-face with the 2-D host layers along the a-axis to form a 3-D supramolecular architecture. There exist C–H?···?N and C–H?···?O weak hydrogen bonds between the guest layer and host layer. These weak hydrogen bonds and water–nitrate, water–water hydrogen bonds are important for the stability of the overall structure.  相似文献   

13.
Polythermal Curves of the Quinary System Na+, K+, Mg2+/Cl?, SO//H2O in Range between +25°C and ?10°C Proceeding from the 0°C, ?5°C and ?10°C isothermal curves of the quinary system Na+, K+, Mg2+/C1?, SO//H2O with saturation at NaCl, KCl, and carnallite, respectively, the polythermal curve is represented between 25°C and ?10°C. Within the new defined range of the polythermal curve the invariant five-salt-paragenesis NaCI, KCI, Glauber's salt (Na2SO4 · 10 H2O), bitter salt (MgSO4 · 7 H2O), Schoenite (K2SO4 · MgSO4 · 6 H2O) can be found at ?7,2°C. It represents also the lowest temperature of formation of Schoenite in this system. It was necessary, moreover, to reconsider further univariant and invariant equilibrium solutions in the range between 25° and 0°C.  相似文献   

14.
The product from reaction of lanthanum chloride heptahydrate with salicylic acid and thioproline, [La(Hsal)2•(tch)]•2H2O, was synthesized and characterized by IR, elemental analysis, molar conductance, thermogravimatric analysis and chemistry analysis. The standard molar enthalpies of solution of LaCl3•7H2O (s), [2C7H6O3 (s)], C4H7NO2S (s) and [La(Hsal)2•(tch)]•2H2O (s) in a mixed solvent of absolute ethyl alcohol, dimethyl sulfoxide (DMSO) and 3 mol•L-1 HCl were determined by calorimetry to be [LaCl3•7H2O (s), 298.15 K]=(-102.36±0.66) kJ•mol-1, [2C7H6O3 (s), 298.15 K]=(26.65±0.22) kJ•mol-1, [C4H7NO2S (s), 298.15 K]=(-21.79±0.35) kJ•mol-1 and {[La(Hsal)2•(tch)]•2H2O (s), 298.15 K}=(-41.10±0.32) kJ•mol-1. The enthalpy change of the reaction LaCl3•7H2O (s)+2C7H6O3 (s)+C4H7NO2S (s)=[La(Hsal)2•(tch)]•2H2O (s)+3HCl (g)+5H2O (l) (Eq. 1) was determined to be =(41.02±0.85) kJ•mol-1. From date in the literature, through Hess’ law, the standard molar enthalpy of formation of [La(Hsal)2•(tch)]•2H2O (s) was estimated to be {[La(Hsal)2•(tch)]•2H2O (s), 298.15 K}=(-3017.0±3.7) kJ•mol-1.  相似文献   

15.
Correlations were determined between heat capacity and temperature and phase change enthalpy of Ba(OH)2·8H2O. The phase diagram and DSC curve of the binary system Na2CO3·10H2O?Na2HPO4·12H2O were determined The kinetics of the dehydrating reaction of Ba(OH)2·8H2O, Na2CO3·10H2O and Na2HPO4·12H2O were measured and theoretically analyzed by TG.  相似文献   

16.
Unusual H-Bonds in Sodium Hydroxide Monohydrate: X-Ray and Neutron Diffraction on NaOH · H2O and NaOD · D2O, respectively X-ray data revealed the structure of NaOH · H2O including the H positions. Neutron diffraction on microcrystalline NaOD · D2O was used for comparison of H with D positions: The compound crystallizes in a layer-type structure with the sequence …? /O Na O O Na O/ …? closely related to that of hydrargillite Al(OH)3 with …? /O 2/3 Al O O 2/3 Al O/ …?. Between OH? ions as acceptors and H2O molecules mäandric, one-dimensional infinite strong H-bonds occur with d(O…?O) = 2.66 Å and 2.69 Å. These lie within O-layers that coordinate Na+ ions. Bridge-bonds between OH? ions as donors and H2O molecules as acceptors connect the /O Na O/-layers with d(O…?O) = 3.18 Å.  相似文献   

17.
In the presence of nickel acetate, a chiral ligand, (S)-Hdphp ((S)-N-[di(2-pyridyl)-hydroxy-methyl]-proline), was synthesized in situ by nucleophilic addition of L-proline to di-2-pyridyl ketone. Based on this ligand, three chiral mononuclear complexes, {Ni[(S)-dphp](DMF)(H2O)}(ClO4) (1), {Ni[(S)-dphp](H2O)2}(ClO4)(H2O)1.5 (2), and {Ni[(S)-dphp](SCN)(H2O)} (3), have been obtained and characterized by single-crystal X-ray diffraction, elemental analyses, and infrared spectra. By virtue of charge-assisted O–H?···?O hydrogen-bonding interactions, all the complexes possess double chain structures. The double chains were connected into 2-D networks via π?···?π stacking and CH?···?π interactions in 1. For 2, O–H?···?O hydrogen-bonding interactions between free water molecules and other oxygens as well as π?···?π stacking and CH?···?π interactions extend the chains into a 3-D network. Complex 3 exhibits 3-D structure via O–H?···?S interactions.  相似文献   

18.
The solid‐liquid equilibria in the quinary system Na+, K+//Cl?, SO2?4, B4O2?7‐H2O at 298 K had been studied experimentally using the method of isothermal solution saturation. Solubilities and densities of the solution of the quinary system were measured experimentally. Based on the experimental data, the dry‐salt phase diagram and water content diagram of the quinary system were constructed, respectively. In the equilibrium diagram of the quinary system Na+, K+//Cl?, SO2?4, B4O2?7‐H2O at 298 K, there are five invariant points F1, F2, F3, F4 and F5; eleven univariant curves E1F1, E2F2, E3F3, E4F5, E5F2, E6F4, E7F5, F1F4, F2F4 F1F3 and F3F5, and seven fields of crystallization saturated with Na2B4O7 corresponding to Na2SO4, Na2SO4·10H2O, Na2SO4·3K2SO4 (Gla), K2SO4, K2B4O7·4H2O, NaCl and KCl. The experimental results show that Na2SO4·3K2SO4 (Gla), K2SO4 and K2B4O7·4H2O have bigger crystallization fields than other salts in the quinary system Na+, K+//Cl?, SO2?4, B4O2?7‐H2O at 298 K.  相似文献   

19.
Under the hydrothermal conditions, Nd(NO3)3·6H2O reacted with pyridine‐2,4‐dicarboxylic acid (2,4‐pydcH2) to give a 2D co‐ordination polymer with the empirical formula of C16H18N2Nd2O18×H2O ( 1 ). Pr(NO3)3·6H2O also reacted with 2,4‐pydcH2 to give another 2D coordination polymer (C8H9NO9Pr)2·H2O ( 2 ). The structure of both polymers have been determined by X‐ray diffraction. X‐ray structural analyses show that both polymers contain bridging oxalate (C2O42?) ligands, which might have been formed by the coupling of two CO2?× radicals, released from pydc2? ligands.  相似文献   

20.
Investigation on the System SrO? SiO2? H2O On addition sodium silicate solutions to solutions of Sr(OH)2, at room temperature strontium hydrogensilicates are precipitated which are always amorphous and contain silicate anions of various condensation degrees. At about 100°C at first also amorphous products are formed containing lower- and higher-molecular silicate anions. On standing of these precipitates at about 80°C under the mother liquor, however, cristallization occurs under complete degradation of the higher-molecular anions to monomeric resp. dimeric silicate anions. In dependence on the Na2O: SiO2 ratio of the sodium silicate solutions and on the Sr(OH)2 concentrations the following crystalline compounds are formed: 1.25 SrO · 1 SiO2 · 2 H2O, 3 SrO · 2 SiO2 · 3 H2O and 3 SrO · 2 SiO2 · 4 H2O, with monomeric silicate anions; 2 SrO · 2 SiO2 · 1.5 H2O; 2 SrO · 2 SiO2 · 2 H2O, and 2 SrO · 2 SiO2 · 3 H2O, with dimeric anions.  相似文献   

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