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Ludwig Maier 《Helvetica chimica acta》1967,50(7):1742-1746
A new method for the preparation of dialkylaminomethyl-phosphonous and-phosphinic acids, R2NCH2P(O)H(OH) and (R2NCH2)2P(O)OH, is described. This involves reaction of hypophosphorous acid with hydroxymethyl-dialkyl-amines or a mixture of formaldehyde and a secondary amine. and The crystalline acids form monohydrates which are stable up to the melting points of the acids. The IR. and 31P-NMR. spectra are reported. 相似文献
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Na(NTO)(H2O)的制备、晶体结构及热力学性质研究 总被引:6,自引:0,他引:6
利用氢氧化钠溶液与NTO水溶液进行反应制备了标题化合物并培养出单晶。通过X射线单晶结构分析法测定分子结构和晶体结构,其分子式可表示为Na(NTO)(H2O),晶体属单斜晶系,P21/c空间群,晶体学参数为:a=0.6303(1)nm,b=0.8285(1)nm,c=1.1574(2)nm,β=103.85(1)°,V=0.5868(2)nm^3,Dc=1.925g/cm^3,Z=4,F(000)=344,μ=0.238mm^-1,R=0.0259。通过Na(NTO)(H2O)在水中溶解焓的测定,算得其标准生成焓、晶格焓和晶格能。 相似文献
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The molecular and crystal structures of Ph2P(O)(CH2)2OH and Ph2P(O)CH2(C6H6)OH have been determined. For the first compound the space group is
with unit cell dimensions a=10.505(2), b=13.720(2), c=14.782(3) Å; =72.58(6), =76.95(6), =72.49(6)° for Z=6 (Syntex
diffractometer,MoK radiation, 2996 reflections, R=3.2%). The second compound crystallizes in the space group P212121 with unit cell dimensions a=9.371(3), b=9.014(3), c=18.461(5) Å for Z=4 (DAR-UM diffractometer,CuK radiation, 909 reflections, R=4.9%). In Ph2P(O)(CH2)2OH, three independent molecules differing in structural details are linked by the P=O...O hydrogen bonds (O...H is 1.84, 1.80, and 1.86 Å), to form a chain. In Ph2P(O)CH2(C6H6)OH, the molecules are joined by pairs of the P=O...H–O bonds (O...H is 1.81 Å) to form 16-membered dimeric associates.Institute of Chemical Physics, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 34, No. 3, pp. 109–118, May–June 1993.Translated by T. Yudanova 相似文献
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Hydrothermal syntheses of 2-carboxyethyl(phenyl)phosphinic acid (H2CEPPA) with Bi(NO3)3 and Cd(NO3)2 produce two layered complexes [Bi2(μ3-O)(CEPPA)2]n (1) and [Cd(HCEPPA)2]n (2). Compound 1 is comprised of [Bi4(μ3-O)2(POO)4(COO)4] SBUs which grow into a double wave-like 2D layer with–CH2CH2–spacers. Compound 2 crystallizes in the orthorhombic noncentrosymmetric space group Pca21, exhibiting a double lattice-like layer. Through edge-to-face d???π stacking, a 3D supramolecular framework is formed based on 2D lattices. Topological analyses indicate that 1 and 2 have sql (or Shubnikov tetragonal plane net) and kgd (or Shubnikov (3.6.3.6) plane net) topological networks respectively. 1 and 2 are isolated as single crystal pure phases, which is confirmed by powder XRD. TGA shows high thermal stabilities with decomposition temperatures of 1 and 2 being 373 and 303°C respectively. The fluorescent spectra exhibit fluorescence quenching in 1 and sharp emission at 292 nm in 2, which is assigned to intraligand emission. 相似文献
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The adsorption of H(2)O and its dissociation products, O, H, and OH, on Ag(100) has been studied using an ab initio embedding method. Results at different sites (atop, bridge, and hollow) are presented. The four-fold hollow site is found to be the most stable adsorption site for O, H, and OH, and the calculated adsorption energies are 87.1, 42.7, and 76.2 kcal mol(-1), respectively. The adsorption energy of water at the atop and bridge sites is almost identical with values of 11.1 and 12.0 kcal mol(-1), respectively. The formation of adsorbed OH species by adsorption of water on oxygen-precovered Ag(100) is predicted to be exothermic by 36 kcal mol(-1). 相似文献
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The extraction behavior of tervalent rare-earth metals (Ln) using a heptane solution containing bis(2-ethylhexyl)phosphinic
acid (PIA-8, HR) from 0.1 mol/dm3 sodium perchlorate media was studied. The pH0.5 values and separation factors obtained were compared among the metals. The stoichiometry of the extracted species and the
extraction constants for the present aqueous/heptane system were determined by slope analysis. It is demonstrated that the
rare-earth metals were extracted as monomers LnR3⋅mHR (m=3, 4, 5 or 6), and the extracted species could be stripped into a relatively low concentrated hydrochloric acid. PIA-8
was found to be the most selective extractant for the mutual separation of rare-earth metals among the other phosphinic acids
reported.
Received: 27 February 1996/Revised: 13 May 1996/Accepted: 21 May 1996 相似文献
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《Journal of solid state chemistry》2004,177(4-5):1297-1301
Compound Cu2(H2O)2{O3PCH2N(C2H4)2NCH2PO3} (1) has a pillared layered structure in which the organic groups of N,N′-piperazinebis(methylenephosphonate) are sandwiched between the inorganic layers. Compared with other copper phosphonates with layered or pillared layered structures, the inorganic layer in 1 is unique in that each {CPO3} tetrahedron is corner-shared with three {CuO4N} square pyramids through three oxygen donors. Ferromagnetic interactions are mediated between the metal centers. Crystal data: Pbca, a=10.0830(16) Å, b=9.4517(15) Å, c=13.218(2) Å, V=1259.7(3) Å3, Z=4. 相似文献
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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
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《Solid State Sciences》1999,1(6):321-329
Chemical preparation, crystal structure and infrared absorption spectra are given for a new organic cation dihydrogendiphosphate. The new synthesized compound [C6H5(CH2)2NH3]2H2P2O7; crystallized in the monoclinic system (P21/c space group) with Z = 4 and with the following unit-cell dimensions: a = 19.006(3); b = 10.718(2), c = 10.996(3) Å and β = 98.99(2) °. Its crystal structure was determined and refined down to R = 0,056 by using 3278 independent reflections. As in all atomic arrangements including acidic diphosphate groups; we can observe the formation of an infinite network of anions connected by strong H-bonds. 相似文献
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A new open-framework copper borophosphate was hydrothermally synthesized and structurally characterized. Its structure may be regarded as a layer forming via vertex-sharing BO3(OH) and PO4 tetrahedra bonded together with CuO2(OH)2(H2O)2 octahedral units. The thermal stability and magnetic properties are also discussed. 相似文献
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Yu. I. Sal’nikov G. A. Boos V. V. Neklyudov S. G. Fattakhov M. M. Shulaeva 《Russian Journal of General Chemistry》2012,82(12):1999-2004
Protolytic and complexing properties of 2,4,6-triaminopyrimidine and its associates with bis (hydroxymethyl)phosphinic acid in aqueous solution were studied using pH measurements, spectrophotometry (298 K), and mathematical simulation of equilibria (CPESSP software). The stability constants of the associates formed in solution were calculated. It was found that the said associates and the nitrogen base in their composition did not form innner-sphere complexes with typical complexing agents like doubly charged cations of d-elements and lanthanum(III). 2,4,6-Triaminopyrimidine forms an outer-sphere complex with copper(II) ions to affording tetrachlorocuprate(II) with diprotonated 2,4,6-triaminopyrimidine. 相似文献