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1.
Sodium holmium polyphosphate crystal, NaHo(PO3)4, has been synthesized by the high temperature solution reaction and characterized by X-ray diffraction analysis, EDX, IR, UV-vis-NIR, and PL spectra. The structure belongs to the monoclinic system, space group P21/n with Z = 4, α = 7.181(3), b = 13.059(5) and c = 9.730 (4) ?. It is described as a three-dimensional (3D) architecture made up of [P4O12]4- anionic spiral chains and HoO8 polyhedra by corner-sharing. The 8-coordinated sodium atoms are located in infinite tunnels. The results of EDX and IR spectrum are in good agreement with the crystallographic analysis. In addition, NaHo(PO3)4 exhibits visible light emission in the solid state at room temperature.  相似文献   

2.
The title molecule, 3-(4-(dimethylamino)benzylidene)-l,5-dioxaspiro[5.5] unde- cane-2,4-dione (I), was synthesized and characterized by elemental analysis, IR, UV-vis spectra and X-ray diffraction analysis. The compound belongs to the triclinic system, space group Pi with a = 6.3640(6), b = 7.7404(8), c = 16.2890(18) A, α = 86.860(2), β = 85.837(2), γ = 79.6720(10)°, V = 786.60(14) A3, D, = 1.331 g/cm3, and F(000) = 336. Geometrical structure of the title compound was optimized by density functional theory (DFT) using B3LYP method with 6-31G** as the basis set. The vibrational frequencies were calculated by the DFT method and the results are consistent with the observed frequencies. The electronic absorption spectra were studied with the time- dependent density functional theory (TD-DFT), showing the calculation results in good agreement with the corresponding experimental data.  相似文献   

3.
Surface structures and electronic properties of hypophosphite H2PO2^- on Ni(111) and Ag(111) surfaces were investigated by means of density functional theory at B3LYP/6-31 + +G(d,p) level. The most stable structure was that in which the H2PO2^- adsorbs with its two P--O bonds faced to the substrate surface. The results of the Mulliken population analysis showed that because of the subtle difference of electron configuration, the adsorption energy was larger on the Ni surface than on the Ag surface, and the amounts of both donation and back donation were larger on the Ni(111) surface than on the Ag(111) surface. There were more negative Mulliken charge transfer from H2PO2^- to substrate clusters on Ni surface than on Ag surface and more positive Mulliken charges on P atom in Ni4H2PO2^- than in Ag4H2PO2^-, which means that P atom in Ni4H2PO2^- is easily attacked by a nucleophile such as OH . Thus, H2PO2^- is more easily oxidated on Ni(111) surface than on Ag(111) suface. These results indicated that the silver surface is inactive for the oxidation reaction of the hypophosphite anion.  相似文献   

4.
In order to study the Fe-Cu interactions and their effects on 31p NMR, the structures of mononuclear complex Fe(CO)3fPhzPpy)a 1 and binuclear complexes Fe(CO)3(PhEPpy)z(CuXn) (2: Xn = Cl2^2-, 3: Xn = Cl-, 4: Xn = Br-) are calculated by density functional theory (DFT) PBE0 method. For complexes 1, 3 and 4, the 31p NMR chemical shifts calculated by PBE0-GIAO method are in good agreement with experimental results. The 31p chemical shift is 82.10 ppm in the designed complex 2. The Fe-Cu interactions (including Fe→Cu and Fe←Cu charge transfer) mainly exhibit the indirect interactions. Moreover, the Fe-Cu(I) interactions (mostly acting as σFe-p→4Scu and aFe-C→4Scu charge transfer) in complexes 3 and 4 are stronger than Fe-Cu(Ⅱ) interactions (mostly acting as σFe-p→4Scu and σFe-p←4Sc,) in complex 2. In complex 2, the stronger Fe←Cu interac- tions, acting as σFe-p←44SCu charge transfer, increase the electron density on P nucleus, which causes the upfield 31p chemical shift compared with mononuclear complex 1. For 3 and 4, although a little deshielding for P nucleus is derived from the delocalization of σFe-p→4Scu due to the Fe→Cu interactions, the stronger σFe-c→np charge-transfer finally increases the electron density on P nucleus. As a result, an upfield 31p chemical shift is observed compared with 1. The stability follows the order of 2〉3=4, indicating that Fe(CO)3(PhzPpy)2(CuCl2) is stable and could be synthesized experimentally. The N-Cu(Ⅱ) interaction plays an important role in the stability of 2. Because the delocalization of σFe-p→4SCu and σFe-c→πc-o weakens the a bonds of Fe-C and ~r bonds of CO, it is favorable for increasing the catalytic activity of binuclear complexes. Complexes 3 and 4 are expected to show higher catalytic activity compared to 2.  相似文献   

5.
The title compound 1 has been synthesized by the reaction of H2MoO4,CdCl2,H3PO4,KF,piperazine hexahydrate and water in aqueous solution under mild hydrothermal conditions. Single-crystal X-ray analysis reveals that the title compound crystallizes in the triclinic system,space group P1 with a = 14.049(3),b = 15.972(3),c = 20.043(4) A,α = 85.82(3),β = 81.28(3),γ = 67.15(3)°,V = 4095.9(14) A^3,Mr = 3204.62,Z = 2,Dc = 2.598 g/c^m3,μ = 2.360 mm^-1,F(000) = 3124,the final R = 0.0314,wR = 0.0826 and S = 0.989 for 18592 observed reflections with I 〉 2σ(I). The crystal packing is stabilized by N–H… and O–H… intraand intermolecular hydrogen bonds to form an infinite 3D network.  相似文献   

6.
The crystal structure of the title compound (C18H24N4O7S, Mr = 440.47) was prepared by the condensation of 2,3,4-tri-O-acetyl-β-D-xylopyranosyl isothiocyanate with 4,6-dimethylpyrimidin-2-amine and structurally determined by single-crystal X-ray diffraction. The crystal belongs to the monochnic system, space group P2 1 with a = 7.5500(17), b = 10.498(2), c = 14.208(3) A, β = 99.929(4)°, V = 1109.2(4) A^3, Z = 2, Dc = 1.319 g/cm^3,μ = 0.191, F(000) = 464, Flack = 0.00(15), R = 0.0684 and wR = 0.1103. In the crystal structure, the xylose ring adopts a ^4C1 chair conformation. Due to the hydrogen bonding interaction between N(4)-H(4A) and N(1), the pyrimidine ring is well positioned.  相似文献   

7.
The compound, N-(pyrimidin-2-yl)-N'-methoxycarbonyl-thiourea, has been synthesized. The single crystal structure has been determined by an X-ray diffractometer. The crystal belongs to triclinic with space group P-1 and a=0.72152(4) nm, b=0.8056(4) nm, c=0.90772(5) nm, α= 105.141(4)°, β=94.588(4)°, γ= 115.415(4)°, F(000)= 220, the unit cell volume V=0.45704(4) nm^3, the molecule number in one unit cell Z=2, the absorption coefficient μ=0.333 mm^-1, the calculated density Dc= 1.542 g/cm^3. The theoretical investigation of the title compound was carried out with B3LYP/6-311G, HF/6-311G and MP2/6-311G methods, and the atomic charges and natural bond orbital analysis were also discussed.  相似文献   

8.
A new reduced molybdenum(V) phosphate (H3dien)2(H2dien)2[NaMo12O24 (OH)6 (HEPO4)(HPO4)5(PO4)2]·nH2O (n= 10.92, dien = diethylenetriamine) has been synthesized under hydrothermal conditions and characterized by elemental analyses, IR and X-ray diffraction. C16H96.84MO12N12NaO72.92P8 (Mr = 3046.73) crystallizes in the monoclinic system, space group P21/c with a = 13.3575(18), b = 21.907(3), c = 15.654(2)A, β= 110.22(2)°, V= 4298.4(10) A^3 Dc = 2.354 g/cm^3, Z = 2,μ(MoKcr) = 1.966 mm^-1, F(000) = 2990.4, the final R = 0.0357 and wR = 0.1086 for 8739 observed reflections with I 〉 2σ(I). It consists of sandwich-shaped cluster anions [Na{Mo6P4}2]^10- held together into a three-dimensional supramolecular framework through intermolecular hydrogen-bonding contacts. A probe reaction of the oxidation of acetaldehyde with H2O2 showed that this compound has high catalytic activity in the reaction.  相似文献   

9.
A novel inorganic-organic hybrid compound, {[Co(dien)]4[0aO4)MoV8(wV10.56MoV10.44)4- O33(OH)3]}'nH20 (1, n = 1, dien = diethylenetriamine), has been synthesized hydrothermally and characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the triclinic system with a = 11.927(2), b = 13.328(3), c = 19.306(4)A, a = 93.76(3), β = 94.14(3), γ = 109.99(3)°, V= 2863.2(12) A3, space group P1 and Z = 2 at 173 K. The final full-matrix least-squares refinement converged to R = 0.049 for 9621 observed reflections with 1 〉 2σ(I) and wR = 0.139 for all data (9871) and S = 1.073. Crystal structure analysis shows that 1 contains a kind of the first reported mixed-valence and molybdenum-tungsten mixed-distributed e-Keggin structural polyanion capped by four Co(dien) fragments with the main group element P occupying the center site. These results were further confirmed by energy-dispersive X-ray spectroscopy (EDS), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, Thermogravimetry (TG) and X-ray photoelectron spectroscopy (XPS) analyses.  相似文献   

10.
A novel zinc(H) metal phosphonate compound [Zn(phen)(m-OOCC6H4PO3H)] 1 (phen = phenanthroline) has been synthesized under hydrothermal conditions. Single-crystal X-ray structure analysis reveals that compound 1 belongs to the triclinic system, space group P1 with a = 9.3356(19), b = 10.203(2),c = 10.743(2)A,α = 76.3030(70), β= 69.2317(51), y = 84.3833(74)°,V = 929.4(3) ,A3, Z = 2, C2OH15N2O5PZn, Mr = 459.68, Dc = 1.643 g/cm^3,μ= 1.444, mm^-1, F(000) = 468, the final R = 0.0330 and wR = 0.0848. In the structure, the central ion Zn(H) is five-coordinated, linking three O atoms with one from carboxyl and the other two from phosphonyl group. The remained two coordinate sites were occupied by two N atoms from one phen molecule to form the asymmetric unit. Then every two adjacent asymmetric units are bridged by the O atoms from phosphonate group and carboxyl to give rise to a 1D chain along the b axis. These chains are constructed by weak π-π stacking interactions and C-H…π interactions to generate a 3D supramolecular framework.  相似文献   

11.
The hydrothermal syntheses of a family of new alkali-metal/ammonium vanadium(V) methylphosphonates, M(VO(2))(3)(PO(3)CH(3))(2) (M = K, NH(4), Rb, Tl), are described. The crystal structures of K(VO(2))(3)(PO(3)CH(3))(2) and NH(4)(VO(2))(3)(PO(3)CH(3))(2) have been determined from single-crystal X-ray data. Crystal data: K(VO(2))(3)(PO(3)CH(3))(2), M(r) = 475.93, trigonal, R32 (No. 155), a = 7.139(3) ?, c = 19.109(5) ?, Z = 3; NH(4)(VO(2))(3)(PO(3)CH(3))(2), M(r) = 454.87, trigonal, R32 (No. 155), a = 7.150(3) ?, c = 19.459(5) ?, Z = 3. These isostructural, noncentrosymmetric phases are built up from hexagonal tungsten oxide (HTO) like sheets of vertex-sharing VO(6) octahedra, capped on both sides of the V/O sheets by PCH(3) entities (as [PO(3)CH(3)](2-) methylphosphonate groups). In both phases, the vanadium octahedra display a distinctive two short + two intermediate + two long V-O bond distance distribution within the VO(6) unit. Interlayer potassium or ammonium cations provide charge balance for the anionic (VO(2))(3)(PO(3)CH(3))(2) sheets. Powder X-ray, TGA, IR, and Raman data for these phases are reported and discussed. The structures of K(VO(2))(3)(PO(3)CH(3))(2) and NH(4)(VO(2))(3)(PO(3)CH(3))(2) are compared and contrasted with related layered phases based on the HTO motif.  相似文献   

12.
13.
The new compounds Li(2-x)Na(x)Ni[PO(4)]F (x = 0.7, 1, and 2) have been synthesized by a solid state reaction route. Their crystal structures were determined from single-crystal X-ray diffraction data. Li(1.3)Na(0.7)Ni[PO(4)]F crystallizes with the orthorhombic Li(2)Ni[PO(4)]F structure, space group Pnma, a = 10.7874(3), b = 6.2196(5), c = 11.1780(4) ? and Z = 8, LiNaNi[PO(4)]F crystallizes with a monoclinic pseudomerohedrally twinned structure, space group P2(1)/c, a = 6.772(4), b = 11.154(6), c = 5.021(3) ?, β = 90° and Z = 4, and Na(2)Ni[PO(4)]F crystallizes with a monoclinic twinned structure, space group P2(1)/c, a = 13.4581(8), b = 5.1991(3), c = 13.6978(16) ?, β = 120.58(1)° and Z = 8. For x = 0.7 and 1, the structures contain NiFO(3) chains made up of edge-sharing NiO(4)F(2) octahedra, whereas for x = 2 the chains are formed of dimer units (face-sharing octahedra) sharing corners. These chains are interlinked by PO(4) tetrahedra forming a 3D framework for x = 0.7 and different Ni[PO(4)]F layers for x = 1 and 2. A sodium/lithium disorder over three atomic positions is observed in Li(1.3)Na(0.7)Ni[PO(4)]F structure, whereas the alkali metal atoms are well ordered in between the layers in the LiNaNi[PO(4)]F and Na(2)Ni[PO(4)]F structures, which makes both compounds of great interest as potential positive electrodes for sodium cells.  相似文献   

14.
Two new phosphates, Bi(4.25)(PO4)2O(3.375) and Bi(5)(PO(4))(2)O(4.5), have been analyzed by single-crystal X-ray diffraction in the series Bi(4+x)(PO4)2O(3+3x/2) (0.175 < or = x < or = 1). The syntheses of the compositions ranging from x = 0.175 to 0.475 were carried out by the ceramic route. The compositions from x = 0.175 to 0.475 form a solid solution with a structure similar to that of Bi(4.25)(PO4)2O(3.375), while Bi(5)(PO4)2O(4.5) was isolated from a mixture of two phases. Both of the phases form fluorite-related structures but, nevertheless, differ from each other with respect to the arrangement of the bismuth atoms. The uniqueness in the structures is the appearance of isolated PO(4) tetrahedra separated by interleaving [Bi2O2] units. ac impedance studies indicate conductivity on the order of 10(-5) S cm(-1) for Bi(4.25)(PO4)2O(3.375). Crystal data: Bi(4.25)(PO4)2O(3.375), triclinic, space group P (No. 1), with a = 7.047(1) A, b = 9.863(2) A, c = 15.365(4) A, alpha = 77.604(4) degrees, beta = 84.556(4) degrees, gamma = 70.152(4) degrees, V = 980.90(4) A3, and Z = 4; Bi(5)(PO4)2O(4.5), monoclinic, space group C2/c (No. 15), with a = 13.093(1) A, b = 5.707(1) A, c = 15.293(1) A, beta = 98.240(2) degrees, V = 1130.95(4) A(3), and Z = 8.  相似文献   

15.
报道了一种新的杂多化合物[HN(C_2H_5)_3]_4-[Mo_3~VMo_6~(VI)V_7~(IV)O_(40)(PO_4)]·2[N(C_2H_5)_3]的合成,并用元素分析、EPR、IR谱、及X--射线单晶衍射等手段进行了表征。结果表明,该杂多酸盐属于单斜晶系,空间群P21/n,a=14.0841(3),b=14.2505(3),c=19.6089(3)?b=94.213(1),V=3925.0(1)?,Z=2,Dc=2.171g/cm3,Mr=2566.18,m=2.284mm-1,F(000)=2516,R=0.0477,wR=0.0945.杂多阴离子是1个16金属笼状物,笼中心包含1个PO4四面体客体。  相似文献   

16.
The novel vanadophosphate (DETAH)(DETAH3)3[V18O42(PO4)]·(PO4)·2H2O has been synthesized under hydrothermal conditions and its structure was determined by single-crystal X-ray diffraction. The compound crystallizes in monoclinic, space group C2/c with a = 23.857(3), b = 12.9619(18), c = 20.204(3) , β = 105.692(2)°, V = 6015.0(14) 3, Z = 4, Dc = 2.473 g/cm3, Mr = 2239.68, F(000) = 4432, R = 0.0725, wR = 0.1524 and GOOF = 1.095. The metaloxo cluster contains a novel six-capped pesudo-Keggin structure unit which encloses a disorder PO43- guest.  相似文献   

17.
Wozniak M  Nowogrocki G 《Talanta》1979,26(12):1135-1141
The acids under study differed from one another in length of the carbon chain [N + H(3)(CH(2))(n)PO(3)H(-) for n = 1, 2, 3], substitution on the nitrogen atom [R(1)R(2)N + HCH(2)PO(3)H(-) for R(1) = H; R(2) = Me, Et and R(1) = R(2)= Me, Et] or extent of branching on the carbon atom adjacent to functional groups [N + H(3)CR(3)R(4)PO(3)H(-) for R(3) = H; R(4) = Me, Et, nPr, iPr, nBu and R(3) = R(4) = Me]. Acidity constants and overall stability constants of complexes formed with Ca(II), Mg(II), Co(II), Ni(II), Cu(II), Zn(II) were obtained with the multiparametric refinement programs MUPROT and MUCOMP, applied to potentiometric data, obtained at 25 degrees , in a 0.1M potassium nitrate medium. In the most general case, the existing species are MHA(+), MA, M(OH)A(-), MH(2)A(2), MHA(-)(2) and MA(2-)(2), where A(2-) stands for the fully ionized ligand; preliminary examination of results points out some predominant microscopic forms.  相似文献   

18.
Water-soluble phosphonate-functionalized triaryl phosphine ligands Na(2)[Ph(2)P(4-C(6)H(4)PO(3))].1.5H(2)O (4a), Na(2)[Ph(2)P(3-C(6)H(4)PO(3))].2H(2)O (4b), and Na(2)[Ph(2)P(2-C(6)H(4)PO(3))].2H(2)O (4c), were prepared in 54-56% yields by the transesterification and hydrolysis of the appropriate phosphonic acid diethyl ester precursors. The solubilities of 4a-c in water are compared and the spectroscopic properties studied in detail. The crystal structure of Na(2)[Ph(2)P(4-C(6)H(4)PO(3))(H(2)O)(3)(CH(3)OH)].CH(3)OH (monoclinic, P2(1)/n, a = 6.4457(8) ?, b = 8.1226(8) ?, c = 46.351(3) ?, beta = 92.902(8) degrees, Z = 4) shows a dimeric association via two bridging water molecules and four sodium ions. Reaction of 4a with PtCl(2)(PPh(3))(2) in a biphasic H(2)O/CH(2)Cl(2) mixture gives cis- and trans-Na(4)[PtCl(2){Ph(2)P(4-C(6)H(4)PO(3))}(2)]. 3H(2)O. Palladium dichloride and 4a in H(2)O/benzene catalyzes the carbonylation of benzyl chloride to give phenylacetic acid (91%).  相似文献   

19.
The reaction of UO(2)(NO(3))(2).6H(2)O with Cs(2)CO(3) or CsCl, H(3)PO(4), and Ga(2)O(3) under mild hydrothermal conditions results in the formation of Cs(4)[(UO(2))(2)(GaOH)(2)(PO(4))(4)].H(2)O (UGaP-1) or Cs[UO(2)Ga(PO(4))(2)] (UGaP-2). The structure of UGaP-1 was solved from a twinned crystal revealing a three-dimensional framework structure consisting of one-dimensional (1)(infinity)[Ga(OH)(PO(4))(2)](4-) chains composed of corner-sharing GaO(6) octahedra and bridging PO(4) tetrahedra that extend along the c axis. The phosphate anions bind the UO(2)(2+) cations to form UO(7) pentagonal bipyramids. The UO(7) moieties edge-share to create dimers that link the gallium phosphate substructure into a three-dimensional (3)(infinity)[(UO(2))(2)(GaOH)(2)(PO(4))(4)](4-) anionic lattice that has intersecting channels running down the b and c axes. Cs(+) cations and water molecules occupy these channels. The structure of UGaP-2 is also three-dimensional and contains one-dimensional (1)(infinity)[Ga(PO(4))(2)](3-) gallium phosphate chains that extend down the a axis. These chains are formed from fused eight-membered rings of corner-sharing GaO(4) and PO(4) tetrahedra. The chains are in turn linked together into a three-dimensional (3)(infinity)[UO(2)Ga(PO(4))(2)](1-) framework by edge-sharing UO(7) dimers as occurs in UGaP-1. There are channels that run down the a and b axes through the framework. These channels contain the Cs(+) cations. Ion-exchange studies indicate that the Cs(+) cations in UGaP-1 and UGaP-2 can be exchanged for Ca(2+) and Ba(2+). Crystallographic data: UGaP-1, monoclinic, space group P2(1)/c, a = 18.872(1), b = 9.5105(7), c = 14.007(1) A, beta = 109.65(3)(o) , Z = 4 (T = 295 K); UGaP-2, triclinic, space group P, a = 7.7765(6), b = 8.5043(7), c = 8.9115(7) A, alpha = 66.642(1)(o), beta = 70.563(1)(o), gamma = 84.003(2)(o), Z = 2 (T = 193 K).  相似文献   

20.
1 INTRODUCTION Current research interest is focused on the designof structures built up from octahedral and tetrahedralbuilding blocks[1]. During the wide investigations intransition-metal phosphates for many years, a num-ber of new mixed transition-metal phosphates havebeen reported[2]. A great number of manganese phos-phates were largely discovered as minerals[1]. On theother hand, many vanadium phosphates have alsobeen prepared recently partly because of their poten-tial applications …  相似文献   

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