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1.
Synthesis, Structure, and Properties of Three Tetrasodium Tetrametaphosphimate Hydrates Single crystals of three tetrasodium tetrametaphosphimate hydrates Na4(PO2NH)4 · x H2O with x = 2 and 3, respectively, have been obtained and characterized by single crystal X-ray diffraction. Dimorphous Na4(PO2NH)4 · 3 H2O is formed at RT. It crystallizes monoclinic ( 1 ) or triclinic ( 2 ) (α-Na4(PO2NH)4 · 3 H2O ( 1 ): P21, a = 1002.7(2), b = 1189.7(2), c=1193.1(2)pm, β=104.93(1)°, Z=4; β-Na4(PO2NH)4 · 3 H2O ( 2 ): P 1¯, a = 843.64(9), b = 848.54(10), c = 994.7(2) pm, α = 83.07(1), β = 76.31(1), γ = 87.46(1)°, Z = 2). Compound 2 is formed in the presence of NaCl during the crystallization from aqueous solution. Tetrasodium tetrametaphosphimate dihydrate ( 3 ) is formed at 60 °C (Na4(PO2NH)4 · 2 H2O ( 3 ): C2/c, a = 2225.6(3), b = 513.0(1), c = 1566.7(2) pm, β = 134.21(1)°, Z = 4). In 1 and 2 the P4N4 ring of the tetrametaphosphimate ions attains a saddle and in 3 a twistboat conformation. The conformations of the anions have been analysed using torsion angles, displacement asymmetry parameters, and puckering parameters. The (PO2NH)44– rings of the compounds 1 , 2 , and 3 are linked by N–H · · &mid  相似文献   

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BiGaIn2S6 – Synthesis, Structure, and Properties The novel compound BiGaIn2S6 was obtained in the quaternary system Bi–Ga–In–S. BiGaIn2S6 forms red transparent platelets and exhibits a range of homogeneity between BiGa1In2S6 and BiGa0.8In2.2S6. The compound is a semiconductor with Eg(opt.) = 1.9 eV. – BiGaIn2S6 crystallizes monoclinically forming a new structure type (a = 1112.0 pm, b = 380.6 pm, c = 1228.0 pm, β = 116.30°, Z = 2, space group P21/m, no. 11). The S atoms form strongly corrugated 2 D fragments of the (hc)2 sphere packing type. The In atoms occupy octahedral holes (d(In–S) = 262 pm) and the Ga atoms tetrahedral holes (d(Ga–S) = 234 pm) inside the 2 D-layers. The Bi atoms on the top of trigonal BiS3 pyramids (d(Bi–S) = 265 pm) are at the periphery of the layers and have four additional S ligands from the neigbouring layer at much larger distances (d(Bi–S) = 319 pm). – The bonding of a BiIII sulfide is analyzed for the first time by the Electron Localization Function (ELF).  相似文献   

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K3ReH6 – Synthesis, Structure, and Magnetic Properties K3ReH6 and K3ReD6 were synthesized by the reaction of potassium hydride (deuteride) with rhenium powder under a hydrogen pressure between 3000–3500 bar at 850 K. X-ray investigations on powdered samples and elastic neutron diffraction experiments on the deuterated compound at the triple axis spectrometer TAS 1 in the temperature range 5–600 K led to the atomic arrangement, which corresponds to that of the cryolite with [ReH6]3–-octahedra as characteristic units. Magnetic susceptibility measurements in the temperature range from 3.5 K and room temperature revealed a weak temperature independent paramagnetism. Quantum mechanical calculations confirm these facts and show in detail that the large value of the spin-orbit coupling parameter is essential for the magnetic behaviour.  相似文献   

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In the molecules of both methyl (1RS,3SR,3aRS,6aSR)‐1‐methyl‐3‐(3‐methyl‐1‐phenyl‐1H‐pyrazol‐4‐yl)‐4,6‐dioxo‐5‐phenyloctahydropyrrolo[3,4‐c]pyrrole‐1‐carboxylate, C25H24N4O4, (I), and methyl (1RS,3SR,3aRS,6aSR)‐5‐(4‐chlorophenyl)‐1‐methyl‐3‐(3‐methyl‐1‐phenyl‐1H‐pyrazol‐4‐yl)‐4,6‐dioxooctahydropyrrolo[3,4‐c]pyrrole‐1‐carboxylate, C25H23ClN4O4, (II), the two rings of the pyrrolopyrrole fragment are both nonplanar, with conformations close to half‐chair forms. The overall conformations of the molecules of (I) and (II) are very similar, apart from the orientation of the ester function. The molecules of (I) are linked into sheets by a combination of an N—H...π(pyrrole) hydrogen bond and three independent C—H...O hydrogen bonds. The molecules of (II) are also linked into sheets, which are generated by a combination of an N—H...N hydrogen bond and two independent C—H...O hydrogen bonds, weakly augmented by a C—H...π(arene) hydrogen bond.  相似文献   

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Calcium Rhodium Hydrides –- Synthesis and Structure The two ternary hydrides Ca8Rh5H23 and Ca8Rh6H24 can be synthesised by reacting calcium hydride with rhodium in a hydrogen atmosphere. X-ray investigations on powder samples and elastic neutron diffraction experiments on the deuterated compounds led to the complete structures. Both hydrides crystallise in cubic structure types representing a transition from the K2PtCl6 type to the perovskit type structure. The rhodium deuterium bond lengths and the atomic volume of deuterium were discussed.  相似文献   

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The crystal structures of three quinuclidine‐based compounds, namely (1‐azabicyclo[2.2.2]octan‐3‐ylidene)hydrazine monohydrate, C7H13N3·H2O ( 1 ), 1,2‐bis(1‐azabicyclo[2.2.2]octan‐3‐ylidene)hydrazine, C14H22N4 ( 2 ), and 1,2‐bis(1‐azoniabicyclo[2.2.2]octan‐3‐ylidene)hydrazine dichloride, C14H24N42+·2Cl? ( 3 ), are reported. In the crystal structure of 1 , the quinuclidine‐substituted hydrazine and water molecules are linked through N—H…O and O—H…N hydrogen bonds, forming a two‐dimensional array. The compound crystallizes in the centrosymmetric space group P21/c. Compound 2 was refined in the space group Pccn and exhibits no hydrogen bonding. However, its hydrochloride form 3 crystallizes in the noncentrosymmetric space group Pc. It shows a three‐dimensional network structure via intermolecular hydrogen bonding (N—H…C and N/C—H…Cl). Compound 3 , with its acentric structure, shows strong second harmonic activity.  相似文献   

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Redetermination of Structure and Properties of the Isotypic Sodium Tetraamido Metallates of Aluminium and Gallium Crystals for x-ray structure determination of NaAl(NH2)4 and NaGa(NH2)4 were obtained by the reaction of the metals with ammonia in autoclaves at 100°C and P(NH3) = 60 bar within 7 days. The compounds crystallize isotypic in the space group P21/c with Z = 4 NaAl(NH2)4 a = 7.328(2) Å, b = 6.047(2) Å, c = 13.151(3) Å, β = 94.04(1)° NaGa(NH2)4 a = 7.4087(8) Å, b = 6.0917(5) Å, c = 12.855(2) Å, β = 92.10(1)° The structures were refined inclusively all H-positions of the amide ions. The ternay amides are furthermore characterized by their IR spectra and their thermal behaviour.  相似文献   

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(CH3)2SBr2 – Reactions and Structures (CH3)2SBr2 ( 1 ) is a donor acceptor complex (8-S-3 + 10-Br-2) which reacts with (CH3)2S(?O)NSi(CH3)3 to yield [(CH3)2S(O)?N? S(CH3)2]+Br? ( 2 ). With SbBr3 (CH3)2SBr+SbBr4? ( 3 ) can be isolated. 1 crystallizes monoclinic in the space group P21/c with a = 733.8, b = 734.2, c = 1132.7 pm, β = 92.8° and Z = 4. 2 crystallizes in the orthorhombic space group Pnma with a = 967.2, b = 793.3, c = 1168.3 pm and Z = 4. The SBr and BrBr force constants of 1 are compared with those of S2Br2, 3 and Br2 resp. The nmr and mass spectra of 1 and 2 are communicated.  相似文献   

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Na3RuD7 – Synthesis and Structure Na3RuD7 was synthesized by the reaction of sodium deuteride with ruthenium powder under a hydrogen pressure of 6000 bar at 900 K. X‐ray investigations on powdered samples and elastic neutron diffraction experiments led to the atomic arrangement (space group: P42/mnm), which is characterized by isolated [RuD7]‐anions. The coordination polyhedron formed by the seven deuterium ligands can be described as a distorted pentagonal bipyramide.  相似文献   

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Bisaminophosphanes – Synthesis, Structure, and Reactivity Different pathways for the synthesis of bis(alkylamino)phosphanes RP(N(H)R′)2 are described. t‐BuP(N(H)‐ Dipp)2 (Dipp = 2,6‐i‐Pr2–C6H3) was structurally characterized by single crystal X‐ray diffraction. The reactivity of the compounds was examplarily investigated using t‐BuP(N(H)t‐Bu)2. Its reaction with Me3Al and R2AlH (R = Me, Et, i‐Bu) in 1 : 1 and 1 : 2 stoichiometrie yield monosubstituted compounds of the type t‐BuP(N(H)t‐Bu)(N(AlR2)t‐Bu).  相似文献   

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The light and heavy γ -variety of iron hydroxide have been prepared by oxydation of Fe(OH)2 and Fe(OD)2 with air oxygen. The formation of cristalline γ - FeOOD proceeds only in a very limited range of temperature, Fe2+ concentration, and duration and velocity of the supplied air. Even at optimal conditions established experimentally the cristallites of the heavy variety are not as ideal as those of the light hydroxide prepared at the same circumstances.  相似文献   

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Na3OsH7 – Synthesis, Structure, and Magnetic Properties as well as Investigations on the Existence of the Analogous Ruthenium Compound Na3OsH7 was synthesized by the reaction of sodium hydride with osmium powder under a hydrogen pressure of more than 1500 bar at 870 K. X‐ray investigations on powdered samples and elastic neutron diffraction experiments on the deuterated compound led to the atomic arrangement (space group: P42/mnm), which is characterized by isolated [OsD7]‐anions. The coordination polyhedron formed by the seven deuterium ligands can be described as a distorted pentagonal bipyramide. Magnetic susceptibility measurements in the temperature range between 3.5 K and room temperature revealed a weak temperature independent paramagnetism. Quantum mechanical calculations confirm these facts and show in detail that the large value of the spin‐orbit coupling constant is responsible for the magnetic behaviour of the osmium (IV) compound. To synthesize the analogous ruthenium hydride it was necessary to increase the hydrogen pressure during the reaction up to 5000 bar. X‐ray investigations showed that Na3RuH7 crystallizes in an atomic arrangement isotypic to that of the osmium compound.  相似文献   

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