首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
A series of open‐framework aluminoborates (ABOs), namely, [Zn2(en)5][Al2B10O20] ( 1 ), [Zn(en)(dien)][AlB5O10] ( 2 ), [Zn(en)3][AlB7O12 (OH)2] ( 3 ), [Zn(en)2][AlB5O10] ( 4 ), K7{AlO0.5[BO2(OH)]Zn@[B12O21(OH)3]}?H2O ( 5 ) (en=ethylenediamine, dien=diethylenetriamine) have been made under mild solvothermal conditions and characterized by single‐crystal X‐ray diffraction, powder X‐ray diffraction, elemental analysis, IR and UV/Vis spectroscopy, thermogravimetric analysis, and nonlinear optical determination. They were classified as two types: Compounds 1 – 4 contain intersecting channels and exhibit various 4‐connected nets built by AlO4 tetrahedra and oxo boron clusters, zinc–amine complexes act as the templates ( 1 – 3 ) or directly bond to the walls of the ABO ( 4 ); compound 5 exhibits a double‐layer structure made by nanosized [BO2(OH)]Zn@[B12O21(OH)3] ({BZn@B12}) clusters with Al2O7 dimers, the channels are within the layer. The second harmonic generation (SHG) measurement shows that the SHG responses of 1 – 3 are about 2.5, 1.6, and 0.5 times that of KH2PO4. Compounds 1 – 2 are type I phase‐matchable materials. UV/Vis spectroscopy indicates that compounds 1 – 5 are wide‐band‐gap semiconductors.  相似文献   

2.
Synthesis of amorphous zinc cadmium ammine aqua monophosphates Zn3?x Cd x (PO4). 2n(NH3) · m(H2O) (x = 0.6–2.4, n = 1.3–3.1, m = 2.3–3.4) with variable molar ratio of the cations described. The sequence of thermal transformations of compound [Zn1.5Cd1.5(NH3)1.4(H2O)3.2(PO4)2] with equimolar ratio of cations is studied, and schemes of its transformation into the crystalline zinc cadmium monophosphate Zn1.5Cd1.5(PO4)2 are suggested.  相似文献   

3.
The crystal structure of the new Bi∼3Cd∼3.72Co∼1.28O5(PO4)3 has been refined from single crystal XRD data, R1=5.37%, space group Abmm, a=11.5322(28) Å, b=5.4760(13) Å, c=23.2446(56) Å, Z=4. Compared to Bi∼1.2M∼1.2O1.5(PO4) and Bi∼6.2Cu∼6.2O8(PO4)5, this compound is an additional example of disordered Bi3+/M2+ oxyphosphate and is well described from the arrangement of double [Bi4Cd4O6]8+ (=D) and triple [Bi2Cd3.44Co0.56O4]6+ (=T) polycationic ribbons formed of edge-sharing O(Bi,M)4 tetrahedra surrounded by PO4 groups. According to the nomenclature defined in this work, the sequence is TT/DtDt, where t stands for the tunnels created by PO4 between two subsequent double ribbons and occupied by Co2+. The HREM study allows a clear visualization of the announced sequence by comparison with the refined crystal structure. The Bi3+/M2+ statistic disorder at the edges of T and D entities is responsible for the PO4 multi-configuration disorder around a central P atom. Infrared spectroscopy and neutron diffraction of similar compounds (without the highly absorbing Cadmium) even suggests the long range ordering loss for phosphates. Therefore, electron diffraction shows the existence of a modulation vector q*=1/2a*+(1/3+ε)b* which pictures cationic ordering in the (001) plane, at the crystallite scale. This ordering is largely lost at the single crystal scale. The existence of mixed Bi3+/M2+ positions also enables a partial filling of the tunnels by Co2+ and yields a composition range checked by solid state reaction. The title compound can be prepared as a single phase and also the M=Zn2+ term can be obtained in a biphasic mixture. For M=Cu2+, a monoclinic distortion has been evidenced from XRD and HREM patterns but surprisingly, the orthorhombic ideal form can also be obtained in similar conditions.  相似文献   

4.
Cd2Cu(PO4)2     
During an investigation of the insufficiently known system M1O–M2O–X2O5–H2O (M1 = Cd2+, Sr2+ and Ba2+; M2 = Cu2+, Ni2+, Co2+, Zn2+ and Mg2+; X = P5+, As5+ and V5+), single crystals of the novel compound dicadmium copper(II) bis[phosphate(V)], Cd2Cu(PO4)2, were obtained. This compound belongs to a small group of compounds adopting a Cu3(PO4)2‐type structure and having the general formula M12M2(XO4)2 (M1/M2 = Cd2+, Cu2+, Mg2+ and Zn2+; X = As5+, P5+ and V5+). The crystal structure is characterized by the interconnection of infinite [Cu(PO4)2]n chains and [Cd2O10]n double chains, both extending along the a axis. Exceptional characteristics of this structure are its novel chemical composition and the occurrence of double chains of CdO6 polyhedra that were not found in related structures. In contrast to the isomorphous compounds, where the M1 cations are coordinated by five O atoms, the Cd atom is coordinated by six. The dissimilarity in the geometry of M1 coordination between Cd2Cu(PO4)2 and the isomorphous compounds is mostly due to the larger ionic radius of the Cd cation in comparison with the Cu, Mg and Zn cations. Sharing a common edge, two CdO6 polyhedra form Cd2O10 dimers. Each such dimer is bonded to another dimer sharing common vertices, forming [Cd2O10]n double chains in the [100] direction. The Cu atoms, located on an inversion centre (site symmetry ), form isolated CuO4 squares interconnected by PO4 tetrahedra, forming [Cu(PO4)2]n chains similar to those found in related structures. Conversely, the [Cd2O10]n double chains, which were not found in related structures, are an exclusive feature of this structure.  相似文献   

5.
New complex phosphates of the general formula K2M0.5Ti1.5(PO4)3 (M=Mn, Co) have been obtained from the melting mixture of KPO3, K4P2O7, TiO2 and CoCO3·mCo(OH)2 or Mn(H2PO4)2 by means of a flux technique. The synthesized phosphates have been characterized by the single-crystal X-ray diffraction and the FTIR-spectroscopy. The compounds crystallize in the cubic system with the space group P213 and cell parameters a=9.9030(14) Å for K2Mn0.5Ti1.5(PO4)3 and a=9.8445(12) Å for K2Co0.5Ti1.5(PO4)3. Both phosphates are isostructural with the langbeinite mineral and contain four formula unit K2M0.5Ti1.5(PO4)3 per unit cell. The structure can be described using [M2(PO4)3] framework composed of two [MO6] octahedra interlinked via three [PO4] tetrahedra. The Curie-Weiss-type behavior is observed in the magnetic susceptibility.  相似文献   

6.
Phase equilibrium in the pseudo-quaternary system K2O–MoO3–P2O5–Bi2O3 was studied as three-component solvent K2MoO4–KPO3–MoO3 containing 15 mol% Bi2O3 during slow cooling and spontaneous crystallization. The results of the investigation were shown on a composition diagram, which indicates the crystallization fields of K2Bi(PO4)(MoO4), K5Bi(MoO4)4, BiPO4 and K3Bi5(PO4)6. New phosphate K3Bi5(PO4)6 was characterized by single-crystal X-ray diffraction (space group C2/c, a=17.680(4), b=6.9370(14), c=18.700(4) Å, β=113.79(3)°) and FTIR spectroscopy. The possibility of lone electron pair stereoactivity of bismuth was suggested using the calculations of characteristics of the Voronoi–Dirichlet polyhedra for K3Bi5(PO4)6 and K2Bi(PO4)(MoO4).  相似文献   

7.
Three novel carboxyarylphosphonate polymers {[Zn2(PCP)(H2PCP)(phen)2] · H2O}n ( 1 ), [Zn(HPCP)(4,4′‐bipy)]n ( 2 ), and [Zn3(MCP)2(2,2′‐bipy)]n ( 3 ) [PCP3– = p‐O2C(C6H4)CH2PO33–, MCP3– = m‐O2C(C6H4)CH2PO33– and phen = phenanthroline] were synthesized and characterized by single‐crystal X‐ray diffraction. Compound 1 features a butterfly‐shaped dimer consisting of [Zn4P4O10] tetranuclear units, which are further linked by hydrogen bonds and π–π stacking interactions into a 3D supramolecular framework. In 2 , there is an infinite P–O–Zn inorganic 2D (4,4) layer with the phosphonate moieties of HPCP2– and unidentate 4,4′‐bipy ligands vertically sticking out. As for 3 , the novel [Zn6P4O12] hexanuclear units with “chair“ conformation are tetrahedrally bridged by eight MCP3– to generate a 2D double‐layer, in which the windows are occupied by 2,2′‐bipy molecules. Additionally, 2D correlation analysis of FTIR with thermal perturbation of 3 were discussed. Compounds 1 – 3 exhibit intense solid state fluorescent emissions. Thermogravimetric analyses suggested the very high stability.  相似文献   

8.
Single crystals of oxidephosphates MTi2O2(PO4)2 [M: Fe (dark red), Co (pinkish red), Ni (green)] with edge‐lengths up to 0.4 mm were grown by chemical vapour transport. FeTi2O2(PO4)2 and CoTi2O2(PO4)2 are isotypic to NiTi2O2(PO4)2. The crystal structure of the latter was previously solved from powder data [FeTi2O2(PO4)2 (data for CoTi2O2(PO4)2 and NiTi2O2(PO4)2 in brackets): monoclinic, P21/c, Z = 2, a = 7.394(3) (7.381(6), 7.388(4)) Å, b = 7.396(2) (7.371(5), 7.334(10)) Å, c = 7.401(3) (7.366(6), 7.340(3)) Å, β = 120.20(3) (120.26(6), 120.12(4))°, R1 = 0.0393 (0.0309, 0.0539) wR2 = 0.1154 (0.0740, 0.1389), 2160 (1059, 1564) independent reflections, 75 (76, 77) variables]. The single‐crystal study allowed improved refinement using anisotropic displacement parameters, yielded lower standard deviations for the structural parameters and revealed a small amount of cation disordering. Twinning and cation disordering within the structures are rationalized by a detailed crystallographic classification of the MTi2O2(PO4)2 structure type in terms of group‐subgroup relations. The structure is characterized by a three‐dimensional network of [PO4] tetrahedra and [MIITi2O12] groups formed by face‐sharing of [MIIO6] and [TiO6] octahedra. Electronic absorption spectra of MTi2O2(PO4)2 in the UV/VIS/NIR region show rather large ligand‐field splittings for the strongly trigonally distorted chromophors [MIIO6] (M = Fe, Co, Ni) with interelectronic repulsion parameters beeing slightly smaller than in other phosphates. Interpretation of the spectra within the framework of the angular overlap model reveals a significant second‐sphere ligand field effect of TiIV ions on the electronic levels of the NiII and CoII.  相似文献   

9.
The asymmetric unit of the title compound, dipotassium bis[hexaaquanickel(II)] tris(μ2‐methylenediphosphonato)tripalladium(II) hexahydrate, K2[Ni(H2O)6]2[Pd3{CH2(PO3)2}3]·6H2O, consists of half a {[Pd{CH2(PO3)2}]3}6− anion [one Pd atom (4e) and a methylene C atom (4e) occupy positions on a twofold axis] in a rare `handbell‐like' arrangement, with K+ and [Ni(H2O)6]2+ cations to form the neutral complex, completed by three solvent water molecules. The {[Pd{CH2(PO3)2}]3}6− units exhibit close Pd...Pd separations of 3.0469 (4) Å and are packed via intermolecular C—H...Pd hydrogen bonds. The [KO9] and [NiO6] units are assembled into sheets coplanar with (011) and stacked along the [100] direction. Within these sheets there are [K4Ni4O8] and [K2Ni2O4] loops. Successive alternation of the sheets and [Pd{CH2(PO3)2}]3 units parallel to [001] produces the three‐dimensional packing, which is also supported by a dense network of hydrogen bonds involving the solvent water molecules.  相似文献   

10.
Yellow–orange tetraaquabis(3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olato‐κN3)cadmium(II) dihydrate, [Cd(C8HN4O2)2(H2O)4]·2H2O, (I), and yellow tetraaquabis(3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olato‐κN3)cadmium(II) 1,4‐dioxane solvate, [Cd(C8HN4O2)2(H2O)4]·C4H8O2, (II), contain centrosymmetric mononuclear Cd2+ coordination complex molecules in different conformations. Dark‐red poly[[decaaquabis(μ2‐3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olato‐κ2N:N′)bis(μ2‐3‐cyano‐4‐dicyanomethylene‐1H‐pyrrole‐2,5‐diolato‐κ2N:N′)tricadmium] hemihydrate], [Cd3(C8HN4O2)2(C8N4O2)2(H2O)10]·0.5H2O, (III), has a polymeric two‐dimensional structure, the building block of which includes two cadmium cations (one of them located on an inversion centre), and both singly and doubly charged anions. The cathodoluminescence spectra of the crystals are different and cover the wavelength range from UV to red, with emission peaks at 377 and 620 nm for (III), and at 583 and 580 nm for (I) and (II), respectively.  相似文献   

11.
The phase relations in the cross-section of the K2W2O7-K2WO4-KPO3 containing 15 mol% Bi2O3 were undertaken using flux method. Crystallization fields of K6.5Bi2.5W4P6O34, K2Bi(PO4)(WO4), Bi2WO6, KBi(WO4)2 and their cocrystallization areas were identified. Novel phase K6.5Bi2.5W4P6O34 was characterized by single-crystal X-ray diffraction: sp. gr. P−1, a=9.4170(5), b=9.7166(4), c=17.6050(7) Å, α=90.052(5)°, β=103.880(5)° and γ=90.125(5)°. It has a layered structure, which contains {K7Bi5W8P12O68} layers stacked parallel to ab plane and sheets composed by potassium atoms separating these layers. Sandwich-like {K7Bi5W8P12O68} layers are assembled from [W2P2O13] and [BiPO4] building units, and are penetrated by tunnels with K/Bi atoms inside. FTIR-spectra of K2Bi(PO4)(WO4) and K6.5Bi2.5W4P6O34 were discussed on the basis of factor group theory.  相似文献   

12.
The stability constants and structure of the complexes of CdII and ZnII with 1-ethoxymethylimidazole (ExMeIm), 1-propoxymethylimidazole (PxMeIm), 1-ethoxymethyl-2-methylimidazole (ExMe-2-MeIm) and 1-propoxymethyl-2-methylimidazole (PxMe-2-MeIm) in aqueous solution have been determined by potentiometric methods. ZnII form both tetrahedral and octahedral species with the cited ligands according to the configurational equilibrium type: octahedron tetrahedron, but CdII prefers octahedral coordination of alkoxymethylimidazole complexes in aqueous solution. Retention of the six-coordination form of CdII has also been confirmed by the data obtained for two novel compounds which have been synthesized in the solid state. The crystal and molecular structure of [Cd(ExMeIm)4(NO3)2] (1) has been determined by X-ray diffraction. The coordination geometry around the CdII ion can be considered as slightly distorted tetragonal bipyramidal (CdN4O2). Additionally, another six-coordinate CdII compound with ethoxymethyl-2-methylimidazole [Cd(ExMe-2-MeIm)4(H2O)](NO3)2 (2) has been characterized by spectroscopic (i.r., far i.r., Raman) ES–MS and t.g.a. methods.  相似文献   

13.
Preparation and crystal structure of the novel compound [Bi3I(C4H8O3H2)2(C4H8O3H)5]2Bi8I30 are reported. The title compound is prepared by heating of BiI3 and diethylene glycol at 413 K in a sealed quartz glass tube filled with argon. Deep red single crystals are grown and applied to perform X-ray powder diffraction and X-ray single-crystal diffraction measurements. The compound crystallizes triclinic with space group P-1: Z=2, a=13.217(1) Å, b=15.277(1) Å, c=22.498(1) Å, α=84.33(1), β=73.18(1), γ=67.48(1). [Bi3I(C4H8O3H2)2(C4H8O3H)5]2Bi8I30 comprises the novel polynuclear [Bi8I30]6− anion and [Bi3I(C4H8O3H2)2(C4H8O3H)5]3+ as the cation. Cation as well as the anion can be assumed to represent intermediates between solid BiI3 and BiI3 completely dissolved in diethylene glycol.  相似文献   

14.
Zincselenide- and Zinctellurideclusters with Phenylselenolate- and Phenyltellurolateligands. The Crystal Structures of [NEt4]2[Zn4Cl4(SePh)6], [NEt4]2[Zn8Cl4Se(SePh)12], [Zn8Se(SePh)14(PnPr3)2], [HPnPr2R]2[Zn8Cl4Te(TePh)12] (R = nPr, Ph), and [Zn10Te4(TePh)12(PR3)2] (R = nPr, Ph) In the prescence of NEt4Cl ZnCl2 reacts with PhSeSiMe3 or a mixture of PhSeSiMe3/Se(SiMe3)2 to form the ionic complexes [NEt4]2[Zn4Cl4(SePh)6] 1 or [NEt4]2[Zn8Cl4Se(SePh)12] 2 respectively. The use of PnPr3 instead of the quarternary ammonia salt leads in toluene to the formation of crystalline [Zn8Se(SePh)14(PnPr3)2] 3 . Reactions of ZnCl2 with PhTeSiMe3 and tertiary phosphines result in acetone in crystallisation of the ionic clusters [HPnPr2R]2[Zn8Cl4Te(TePh)12] (R = nPr 4 , Ph 5 ) and in THF of the uncharged [Zn10Te4(TePh)12(PR3)2] (R = nPr 6 , Ph 7 ). The structures of 1–7 were obtained by X-ray single crystal structure. ( 1 : space group P21/n (No. 14), Z = 4, a = 1212,4(2) pm, b = 3726,1(8) pm, c = 1379,4(3) pm β = 99,83(3)°; 2 space group P21/c (Nr. 14), Z = 4, a = 3848,6(8) pm, b = 1784,9(4) pm, c = 3432,0(7) pm, β = 97,78(3)°; 3 : space group Pnn2 (No. 34), Z = 2, a = 2027,8(4) pm, b = 2162,3(4) pm, c = 1668,5(3) pm; 4 : space group P21/c (No. 14), Z = 4, a = 1899,8(4) pm, b = 2227,0(5) pm, c = 2939,0(6) pm, β = 101,35(3)°; 5 : space group space group P21/n (No. 14), Z = 4, a = 2231,0(5) pm, b = 1919,9(4) pm, c = 3139,5(6) pm, β = 109,97(4)°; 6 : space group I41/a (No. 88), Z = 4, a = b = 2566,0(4) pm, c = 2130,1(4) pm; 7 : space group P1¯ (No. 2), Z = 2, a = 2068,4(4) pm, b = 2187,8(4) pm, c = 2351,5(5) pm, α = 70,36°, β = 84,62°, γ( = 63,63°)  相似文献   

15.
《Solid State Sciences》1999,1(2-3):109-118
K3[Cu3FZn2(PO4)4] has been prepared by hydrothermal synthesis and the crystal structure was determined by single crystal X-ray analysis: space group C2/c, a = 37.824(8), b = 9.813(2), c = 16.679(3) Å, β = 92.70(3)°, wR2 = 0.057, R = 0.0255. An open framework structure is built by [CuO5] and [CuO4F] square pyramids, [CuO4] flattened tetrahedra, [ZnO4] and [PO4] tetrahedra with potassium ions in the channels.  相似文献   

16.
Three unprecedented 2D architectures made up of sandwich‐type tetra‐metal‐substituted polyoxotungstates and transition‐metal complexes, [Cu(dien)(H2O)]2{[Cu(dien)(H2O)]2‐[Cu(dien)(H2O)2]2[Cu4(SiW9O34)2]}? 5H2O ( 1 ; dien=diethylenetriamine), [Zn(enMe)2(H2O)]2{[Zn(enMe)2]2[Zn4‐ (HenMe)2(PW9O34)2]}?8H2O ( 2 ; enMe =1,2‐diaminopropane), and [Zn(enMe)2‐(H2O)]4[Zn(enMe)2]2{(enMe)2{[Zn‐ (enMe)2]2[Zn4(HSiW9O34)2]}{[Zn‐ (enMe)2(H2O)]2[Zn4(HSiW9O34)2]}}? 13H2O ( 3 ) were hydrothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and single‐crystal X‐ray diffraction. Compound 1 consists of anions [Cu4(SiW9O34)2]12? linked by copper complexes into a 2D structure, whereas 2 is constructed from novel inorganic–organic hybrid anions [Zn4(HenMe)2(PW9O34)2]8? linked by zinc complexes into a 2D structure. The most interesting is the unique 2D network 3 , which consists of anions [Zn4(PW9O34)2]10? with two types of bridging groups: zinc complexes and enMe ligands.  相似文献   

17.
A new potassium bismuth phosphate-molybdate K2Bi(PO4)(MoO4) has been synthesized by the flux method and characterized by single-crystal and powder X-ray diffraction, IR spectroscopic studies. The compound crystallizes in the orthorhombic system with the space group Ibca and the cell parameters: a=19.7037(10), b=12.4752(10), c=7.0261(10). This phase exhibits an original layered structure, in which the [Bi(PO4)(MoO4)] layers consist of [Bi2Mo2O18] chains linked through single PO4 tetrahedra. The K+ cations interleaved between these layers exhibit a monocapped distorted cubic coordination.  相似文献   

18.
Reaction of [Zn44-O)(O2CCH3)6] with one equivalent of 4-tertiary-butylpyridine leads to a nearly quantitative formation of the heptanuclear cluster [Zn7O2(O2CCH3)10(tbupy)2] (1). Here, we present the crystal structure of 1 and first results of the examination of its catalytic activity in transesterification reactions and polymerization of lactide compared to the activity of [Zn44-O)(O2CCH3)6] in the presence of 4-tertiary-butylpyridine.  相似文献   

19.
The two‐dimensional zinc phosphate [H3N(CH2)3NH3]0.5[Zn2(PO4)(HPO4)], has been synthesized hydrothermally using 1,3‐diaminopropane as the template. Its structure contains an inorganic framework with three‐, four‐, or six‐membered rings, built from PO4, PO3(OH) and ZnO4 tetrahedral moieties sharing vertexes. The protonated 1,3‐diaminopropane molecules interact with the framework through hydrogen bonds. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

20.
Single crystals of the new Bi(III) phosphates, Rb6Bi4(PO4)2(P2O7)3, have been isolated and their structure has been determined by X-ray diffraction techniques. This compound crystallizes in the monoclinic space group P21/c with a=9.077(1)Å, b=9.268(2)Å, c=36.418(6)Å, β=95.75(1)° and Z=8. The crystal structure is made up of BiO5 and BiO6 polyhedra sharing the corners with PO4 tetrahedra and P2O7 diphosphate groups. The structure can be described as infinite anionic layers with composition [Bi4(PO4)2(P2O7)3]6− parallel to the [301] plane, connected via P-O-Bi bridges to form a three-dimensional open framework. This framework delimits tunnels running along [100] and [010] directions, where the rubidium ions reside. This compound exhibits a rubidium ion conduction but with rather low conductivity value at 640 K.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号