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1.
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   

2.
Crystal Structure of CaZn2(OH)6 · 2 H2O The electrochemical oxidation of zinc in a zinc/iron-pair leads in an aqueous NH3 solution of calciumhydroxide at room temperature to colourless crystals of CaZn2(OH)6 · 2 H2O. The X-ray structure determination was now successful including all hydrogen positions. P21/c, Z = 2, a = 6.372(1) Å, b = 10.940(2) Å, c = 5.749(2) Å, β = 101.94(2)° N(F ≥ 3σF) = 809, N(Var.) = 69, R/RW = 0.011/0.012 The compound CaZn2(OH)6 · 2H2O contains Zn2+ in tetrahedral coordination by OH? and Ca2+ in octahedral coordination by four OH? and two H2O. The tetrahedra around Zn2+ form corner sharing chains, three-dimensionally linked by isolated polyhedra around Ca2+. Weak hydrogen bridge bonds result between H2O as donor and OH?.  相似文献   

3.
Characterization of Distortional Isomers of the Anions Pentacyano-oxo-molybdate(IV) and of Tetracyano-aqua-oxo-molybdate(IV) in the Solid State. Crystal Structures of [(C6H5)4P]3[MoO(CN)5] · 7 H2O (green), [(C6H5)4As]2[MoO(OH2)(CN)4] · 4 H2O (blue), and [(C6H5)4P]2[MoO(OH2) (CN)4] · 4 H2O (green) Preparation of a series of salts containing the new pentacyano-oxo-molybdate(IV) anion is described: Cs2H[MoO(CN)5] (blue), [(CH3)4N]2H[MoO(CN)5] · 2 H2O (blue) and [Cr(en)3] [MoO(CN)5] · 4 H2O (green). The green [(C6H5)4P]3[MoO(CN)5] · 7 H2O crystallizes triclinic in the space group P1 . The molybdenum(IV) center is in an pseudo-octahedral environment of a terminal oxo-group (d(Mo?O); 1.705(4) Å), a CN? group in the trans-position (d(Mo? C): 2.373(6) Å), and four equatorial CN? groups (averaged d(Mo? C): 2.178 (Å). The blue and green salts exhibit v(Mo?O) stretching frequencies at 948 cm?1 and 920 cm?1, respectively. Blue and green salts containing the [MoO(OH2)(CN)4]2? anion and [(C6H5)4P]+ or [(C6H5)4As]+ cations have been prepared and characterized by single crystal crystallography. [(C6H5)4P]2[MoO(OH2)(CN)4] · 4 H2O (green) and [(C6H5)4As]2[MoO(OH2)(CN)4] · 4 H2O (blue) crystallize monoclinic in the space group C—P21/n. They are considered to be distortional isomers of the complex anion: the green species has a Mo?O bond distance of 1.72(2) Å whereas for the blue species d(Mo?O) = 1.60(2) Å is found; the corresponding v(Mo?O) frequencies are at 920 cm?1 and 980 cm?1.  相似文献   

4.
Hydrates of Weak and Strong Bases. XI. The Crystal Structures of NaOH · 3,5H2O and NaOH · 7 H2O. A Refinement The crystal structures of the hydrates NaOH · 3,5 H2O (space group P21/c, Z = 8 formula units per unit cell; lattice parameters: a = 6.481, b = 12.460, c = 11.681 Å, β = 104.12° at ?100°C) and NaOH · 7 H2O (P21/c, Z = 4; a = 7.344, b = 16.356, c = 6.897 Å, β = 92.91° at ?150°C) have been redetermined using MoKα diffractometer data. The obtained refinement of the structures, including the localization also of the H atoms for the first time, has led to new findings with respect to the H bonds. In particular, in both hydrates there is one such interaction of the rare type OH? …? OH2, from an OH? ion to an H2O molecule, i. e. with the OH? ion as the proton donor.  相似文献   

5.
Crystal Structure of SrZn(OH)4 · H2O Colorless crystals of SrZn(OH)4 · H2O are obtained by electrochemical oxidation of Zn in a zinc/iron pair in an aqueous ammonia solution saturated with strontium hydroxide. The X-ray crystal structure determination was now successful including all hydrogen positions: P1 , Z = 2, a = 6.244(1) Å, b = 6.3000(8) Å, c = 7.701(1) Å, α = 90.59(1)°, β = 112.56(2)°, γ = 108.66(2)°, N(F ≥ 3σF) = 1967, N(Var.) = 84, R/Rw = 0.020/0.024. In SrZn(OH)4 · H2O Zn2+ is tetrahedrally coordinated by four OH? -ions while Sr2+ has 6 OH? and one H2O as neighbours. The polyhedra around Sr2+ are connected to chains which are linked three-dimensionally by isolated tetrahedra [Zn(OH)4]. Hydrogen bonds between H2O as donor and OH? are characterized by raman spectroscopy.  相似文献   

6.
In tetraethyl­ammonium hydro­xide tetrahydrate, C8H20N+·­OH?·­4H2O, the array of mirror symmetric NEt4+ cations gives rise to a system of parallel channels which are filled with hydrogen‐bonded anionic ribbons. The central part of each ribbon is constituted by a [OH?(HOH)4/2] spiro‐chain, with each hydro­xide ion accepting four strong linear hydrogen bonds [d(O?O) between 2.692 (1) and 2.727 (1) Å] but donating none. Additional (two‐coordinate) H2O mol­ecules bridge between the (four‐coordinate) H2O mol­ecules of the spiro‐chain [d(O?O) between 2.831 (1) and 2.835 (1) Å].  相似文献   

7.
Hydroxides of Sodium, Potassium, and Rubidium: Crystal Growth and X-ray Structure Determination of the Modification Stable at Room Temperature NaOH powder can be recrystallized at 523 to 473 K from NH3 at 6 kbar pressure within 10 d in the form of transparent crystal plates which are very sensitive to mechanical deformation; they split into slices. Under comparable conditions the protolysis of KNH2 and RbNH2, with K(H2O)OH and Rb(H2O)OH, respectively, at temperatures <423 K and <365 K leads to platelets of crystals of KOH and RbOH. The crystal growth was carried out within the range of stability of the corresponding stable room temperature modification. The x-ray diffraction of single crystals gives new information about the atomic arrangement in the three compounds: For NaOH the positions of the H atoms result (measurements at 294 K and 147 K), the x-ray structure of NaOH has been known as to the Na and O arrangement. It is of the TlI-type structure. The OH? ions are quadratic pyramidaly coordinated by Na+ ions. They form linear Na? O? H groups with the Na+ ion at the top of the pyramide. This gives H double layers within the structure; they are responsible for the easy cleavage of the crystals perpendicular to the direction [010]. KOH and RbOH are isotypic. They have a monoclinically deformed NaCl-type structure for the heavier atoms. The OH? ions librate at room temperature. So the positions of the H atoms even in KOH could not be detected by x-ray structure determination.  相似文献   

8.
Crystal Structure and Data from Vibrational Spectra of cis-Na2[Pd(SO3)2en] · 4 H2O The compound cis-Na2[Pd(SO3)2en] · 4 H2O (en = 1,2-diaminoethane) crystallizes in the orthorhombic space group Pnma with a = 623.7(2), = 1070.9(10), c = 1989.5(30) pm and Z = 4. In the [Pd(SO3)2en]2? anions the trans-influence of the sulfite ligands manifests itself in long Pd? N bonds with short Pd? S distances. A set of Na+ ions is present in face-sharing octahedra Na(OH2)6+, forming rods [Na(OH2)6/2]+ parallel to [100]. A second set of Na+ ions is surrounded by two H2O molecules and four O atoms from SO3 ligands of two anions to form likewise octahedra with face-sharing, yielding rods [Na(OH2)2/2{(OSO2)2Pd en}2/2]? parallel to [100]. Comparatively low v(Pd? N)-frequencies reveal the trans-influence of the sulfite ligands also in the vibrational spectra.  相似文献   

9.
Crystal Structure of Sr(BrO3)2 · H2O, Ba(BrO3)2 · H2O, Ba(IO3)2 · H2O, Pb(ClO3)2 · H2O, and Pb(BrO3)2 · H2O The crystall structures of the isostructural halates Sr(BrO3)2 · H2O, Ba(BrO3)2 · H2O, Ba(IO3)2 · H2O, Pb(ClO3)2 · H2O, and Pb(BrO3)2 · H2O were determined using X-ray single crystal data (monoclinic space group C2/c? C, Z = 4), The mean bond lengths and bond angles of the halate ions in the Ba(ClO3)2 · 1 H2O-type compounds, which correspond to those of other halates, are Cl? O, 149.0, Br? O, 165.9, I? O, 180.2 pm, ClO3?, 106.4, BrO3?, 104.0, and IO3?, 99.6°. The structure data obtained are discussed in terms of possible orientational disorder of the water molecules, strengths of the hydrogen bonds, influence of the lead ions on the structure, and site group distortion of the halate ions.  相似文献   

10.
The Crystal Structure of the 1:1 Addition Compound between Antimony Trichloride and Diphenylammonium Chloride, SbCl3 · (C6H5)2NH2+Cl? The 1:1 addition compound between antimony trichloride and diphenylammoniumchloride SbCl3 · (C6H5)2NH2+Cl? crystallizes in the monoclinic space group P21/n with a = 5.668(8), b = 20.480(12), c = 14.448(17) Å, β = 110.4(1)° and Z = 4 formula units. Chains of SbCl3 molecules and anion cation chains are bridged by Cl ions and form square tubes. The coordination of the Sb atoms by Cl atoms by Cl atoms and Cl ions is distorted octahedral. Mean distances are Sb? Cl = 2.37 Å for Sb? Cl (3×), 3.09 Å for Sb…Cl? (2×) and 3.42 Å for Sb…Cl (1×). The Sb…Cl? contacts and hydrogen bonds NH…Cl? at 3.15 Å generate tetrahedral coordination of the Cl ions.  相似文献   

11.
Rb2I(OH): A Hydroxide Iodide in the System RbOH/RbI The pseudobinary system RbOH/RbI was investigated by X-ray methods. The crystal structure of Rb2I(OH) was solved by single crystal data: Rb2I(OH): Pnma, Z = 4, a = 7.748(1) Å, b = 5.654(2) Å,c = 13.254(2) Å Z(Fo) with (Fo)2 ? 3σ = (Fo)2 = 449, Z (parameter) = 25, R/Rw = 0.021/0.023 Rb2I(OH) crystallizes in a new type of structure, built up by a three dimensional network of [Rb2(OH)+] containing the iodide ions.  相似文献   

12.
Hydroxide Monohydrates of Potassium and Rubidium; Compounds with Atomic Arrangements which Suggest the Formula K(H2O)OH and Rb(H2O)OH Single crystals for x-ray structure investigations of the monohydrates of potassium and rubidium hydroxides were obtained by recrystallization of microcrystalline sampels in supercritical ammonia as solvent. The structure determination on both structurally closely related compounds was successful up to the localization of the hydrogen positions. Besides the monohydrates were characterized by IR spectra and thermochemical data. The atomic arrangement of the compounds is discussed in comparison to the one of substances as PbFCl, γ-AlOOH etc. In addition to the chemical bonds in the stated compounds both monohydrates show one-dimensional infinite hydrogen bridges between the H atoms of the water molecules and the hydroxide ions; furthermore weak H bonds connect the OH? ions. Because the hydroxide ions are involved in two bridge-bindung systems water molecules are the nearest neigh-bours of the cations.  相似文献   

13.
The title compound, C36H44N6O4+·2Cl?·2ClO4?·0.132H2O, is shown to be protonated at all the pyridine N atoms; the two chloride ions are hydrogen bonded to three pyridine N atoms and to the phenolic O atom of the same cation [Cl?N = 3.045 (2)–3.131 (2) Å and Cl?O = 2.938 (2) Å], and the remaining pyridine N atom is hydrogen bonded to the phenolic O atom [N?O = 2.861 (2) Å]. The mean value of the C—N—C angle of the protonated pyridine rings is 123.4 (1)°, which is significantly larger than that found for unprotonated pyridine rings.  相似文献   

14.
Crystal Structures of Sr(OH)2 · H2O, Ba(OH)2 · H2O (o.-rh. and mon.), and Ba(OH)2 · 3 H2O The crystal structures of Ba(OH)2 · 3 H2O (Pnma, Z = 4), γ-Ba(OH)2 · H2O (P21/m, Z = 2) and the isotypic Sr(OH)2 · H2O and β-Ba(OH)2 · H2O (Pmc21, Z = 2) were determined using X-ray single crystal data. Ba(OH)2 · 3 H2O and Ba(OH)2 · H2O mon. crystallize in hitherto unknown structure types. The structure of Ba(OH)2 · H2O mon. is strongly related to that of rare earth hydroxides M(OH)3 with space group P63/m (super group of P21/m). The metal-oxygen distances are significantly shorter for OH? ions (mean Ba—O bond lengths of all hydroxides under investigation 278.1 pm) than for H2O molecules (289.9 pm). Corresponding to other hydrates of ionic hydroxides, the water molecules form strong hydrogen bonds to adjacent OH? ions whereas the hydroxide are not H-bonded.  相似文献   

15.
Selenostannates from Aqueous Solutions: Preparation and Structure of Na4SnSe4 · 16 H20 Pure selenostannates(IV) are prepared from aqueous solutions by reaction of SnSe2, with alkali selenides, strictly excluding oxygen. Na4SnSe4 · 16 H2O, being obtained from stoicheo-metric 1:2 quantities, is characterized by a complete X-ray structure analysis and by vibrational spectra. The compound is monoclinic (P21/m) with a = 8.673(3), b = 16.563(4), c = 8.647(2) Å, β = 92.10(2)°, Z = 2; it contains isolated tetrahedral SnSe44? ions [Sn? Se 2.504(2)?2.527(2) Å, Se? Sn? Se 106.6(1)?111.1(1)°] which are in contact to the hydrated octahedral [Na(OH2)6]+ ions through Se…?H? O bridges within an extensive hydrogen bridge system. The stretching vibrations of the SnSe44? ion are observed at 195 (n?1) and 252 cm?1 (n?3). The stretching force constant is approximately 1.59 mdyn/Å.  相似文献   

16.
(Phenacetin)4·2I4·2H2O is triclinic, a = 13.641 (7), b = 12.807 (6), c = 7.201 (3) Å, α = 99.8 (4), b? = 86.5 (4), γ = 104.0 (5)°, P1 , Z = 1. The ordered crystal structure has been refined to RF = 0.050, using 4173 independent reflections measured on a four-circle diffractometer with MoKa (graphite monochromator) radiation. The crystals are composed of alternating positively and negatively charged slices; each positive slice contains a double layer of stacks of hemi-protonated phenacetin molecules which are H-bonded through their carbonyl groups (d(O - - - O) = 2.432 (4) Å) while each negative slice contains a single layer of I2?4-ions linked in chains along [100] through H-bonds to pairs of water molecules. The axes of the phenacetin stacks are parallel to the planes of the (I2?4·2H2O)-layers. The I2?4-ion is centro-symmetric and can be approximately represented as I?- - - I–I- - - I? (d(I? - - - I) = 3.404 (1) Å; d(I–I) = 2.774 (1) Å). The compound is a pseudo-type A basic salt.  相似文献   

17.
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   

18.
Potassium Amido Trioxo Germanates(IV) – Hydrogen Bridge Bonds in K3GeO3NH2 and K3GeO3NH2 · KNH2 Colorless crystals of K3GeO3NH2 and of K3GeO3NH2 · KNH2 were obtained by the reaction of KNH2 with GeO2 in supercritical ammonia at 450°C and p = 6 kbar in high-pressure autoclaves within 15 resp. 5 days. The crystal structures of both compounds were solved by X-ray single crystal methods. K3GeO3NH2: P1 , a = 6.390(1) Å, b = 6.684(1) Å, c = 7.206(1) Å, α = 96.47(1)°, β = 101.66(1)°, γ = 91.66(1)°, Z = 2, R/Rw = 0.020/0.022, N(I) ≥ 2σ(I) = 3023, N(Var.) = 82 K3GeO3NH2 · KNH2: P21/c, a = 10.982(6) Å, b = 6.429(1) Å, c = 12.256(8) Å, β = 106.12(1)°, Z = 4, R/Rw = 0.022/0.029, N(F) ≥ 3σ(F) = 1745, N(Var.) = 107. In K3GeO3NH2 tetrahedral ions GeO3NH23? are connected to chains by N? H …? O bridge bonds with 2.18 Å ≤ d(H …? O) ≤ 2.40 Å for d(N? H) ? 1.0 Å and by potassium ions while in K3GeO3NH2 · KNH2 bridge bonds between NH2 groups of GeO3NH23? and NH2? ions as acceptors occur with 2.41 Å ≤ d((N? )H …? NH2?) ≤ 2.61 Å for d(N? H) ? 1.0 Å.  相似文献   

19.
The reaction of [HN(n-C4H9)3]3[WV(CN)8]·4H2O, 4,4′-bipyridine dioxide(4,4′-dpdo), and MnCl2·4H2O or CuCl2·2H2O gives two new three-dimensional octacyanometalate-based bimetallic assemblies, {[Mn2 (4,4′-dpdo)(H2O)4] [WIV(CN)8]}·6H2O (1) and {[Cu2(4,4′-dpdo)(H2O)][W(CN)8]}·CH3OH·H2O (2). Compound 1 crystallizes in the orthorhombic system, space group P21212 with cell constants a=10.397(2) -, b= 11.321(2) -, c=12.295(3) - and Z=2, whereas 2 crystallizes in the monoclinic system, space group P21/c with cell con...  相似文献   

20.
The title compound, [H2bipy](ClO4)2 or C10H10N22+·2ClO4?, was obtained at the interface between an organic (2,2′‐bi­pyridine in methanol) and an aqueous phase (perchloric acid in water). The compound crystallizes in space group P and comprises discrete diprotonated trans‐bipyridinium cations, [H2bipy]2+, and ClO4? anions. The cations and anions are connected through N—H?O and C—H?O hydrogen bonds [distances N?O 2.817 (4) and 2.852 (4) Å, and C?O 3.225 (6)–3.412 (5)Å]. The C—C bond distance between the two rings is 1.452 (5) Å. The bipyridinium cation has a trans conformation and the N—C—C—N torsion angle is 152.0 (3)°.  相似文献   

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