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1.
1 INTRODUCTION The synthesis of porous and open-framework transition metal phosphates has received great in- terest due to their various compositions and topolo- gyies, as well as their useful properties such as con- trollable size- and shape-selectivity, rigid frame- works and chemical/thermal stability[1]. Of these phosphates constructed from oxometal polyhedra and PO4 tetrahedron, the most interesting is the [MoV6P4X31]n- (X=O, OH) family with the dimen- sionalities ranging from …  相似文献   

2.
Two asymmetric polyoxomolybdates Na(6){Mo(2)O(5)[(Mo(2)O(6))NH(3)CH(2)CH(2)CH(2)C(O)(PO(3))(2)](2)}·16H(2)O (1) and (NH(4))(7)Na{MoO(2)[(Mo(2)O(6))NH(3)CH(2)CH(2)CH(2)C(O)(PO(3))(2)]}(4)·H(2)O (2) have been synthesized by the reactions of alendronic acid with molybdate. Structure analysis revealed that the polyoxoanions 1 and 2 can be described as dimeric and tetrameric aggregates of the {MoO(3)[(Mo(2)O(6))NH(3)CH(2)CH(2)CH(2)C(O)(PO(3))(2)]} units respectively. Their tetrabutylammonium salts show efficient selective oxidation of benzyl alcohol to benzaldehyde with 72.5% and 81.5% benzyl alcohol conversion, and 87.1% and 82.4% benzaldehyde selectivity, respectively.  相似文献   

3.
Hydrothermal reactions of a vanadate source, an appropriate Cu(II) source, bisterpy and an organodiphosphonate, H2O3P(CH2)nPO3H2(n= 1-5), in the presence of HF, yielded a family of materials of the type oxyfluorovanadium/copper-bisterpy/organodiphosphonate. Under similar reaction conditions, variations in diphosphonate tether length n provided the one-dimensional [{Cu2(bisterpy)}V2F2O2{HO3PCH2PO3}{O3PCH2PO3}](1) and [{Cu2(bisterpy)}V2F4O4{HO3P(CH2)2PO3H}](3), the two-dimensional [{Cu2(bisterpy)}V2F2O2(H2O)2{HO3P(CH2)2PO3}2] x 2H2O (2 x 2H2O), [{Cu2(bisterpy)(H2O2}V2F2O2{O3P(CH2)3PO3}{HO3P(CH2)3PO3H}(4) and [{Cu2(bisterpy)}V4F4O4(OH)(H2O){HO3P(CH2)5PO3}{O3P(CH2)5PO3}] x H2O (9 x H2O) and the three-dimensional [{Cu2(bisterpy)}3V8F6O17{HO3P(CH2)3PO3}4]0.8H2O (5 x 0.8H2O), [{Cu2(bisterpy)}V4F2O6{O3P(CH2)4PO3}2](8) and [{Cu2(bisterpy)(H2O)}2V8F4O8(OH)4{HO3P(CH2)5PO3H}2{O3P(CH2)5PO)}3] x 4.8H2O (10 x 4.8H2O). In addition, two members of the oxovanadium/Cu2(bisterpy)/organodiphosphonate family [{Cu2(bisterpy)}V2O4{HO3P(CH2)3PO3}2](6) and [{Cu2(bisterpy)}3V4O8(OH)2{O3P(CH2)3PO3}2{HO3P(CH2)3PO3}2] x 5H2O (7 x 5H2O) cocrystallized from the reaction mixture which provided 5. The overall architectures reveal embedded substructures based on V/P/O(F) clusters, chains, networks, and frameworks. In contrast to the oxovanadium/Cu2(bisterpy)/ organodiphosphonate family, several of the materials of this study also exhibit the direct condensation of vanadium polyhedra to produce binuclear and/or tetranuclear building units.  相似文献   

4.
Hydrothermal reactions of solutions containing a vanadate source, an organodiphosphonate, an organonitrogen component, and HF (V/P/O/F) yield a series of oxyfluorovanadium-diphosphonates with charge-compensation provided by organoammonium cations or hydronium cations. While V/P/O/F networks provide the recurrent structural motif, the linkage between the layers and the details of the polyhedral connectivities within the layers are quite distinct for the five structures of this study. [H2pip][V4F4O2(H2O)2{O3P(CH2)3PO3}2] (1) (pip = piperazine) is a conventional three-dimensional (3D) "pillared" layer structure, whose V/P/O/F networks are buttressed by the propylene chains of the diphosphonate ligands. In contrast, [H2en][V2O2F2(H2O)2{O3P(CH2)4PO3}] (2) and [H2en]2[V6F12(H2O)2{O3P(CH2)5PO3}2 {HO3P(CH2)5PO3H}] (3) are two-dimensional (2D) slablike structures constructed of pairs of V/P/O/F networks sandwiching the pillaring organic tethers of the diphosphonate ligands. Despite the common overall topology, the layer substructures are quite different: isolated {VO5F} octahedra in 2 and chains of corner-sharing {VO(3)F(3)} octahedra in 3. The 3D structure of [H2en]2[V7O6F4(H2O)2{O3P(CH2)2PO3}4].7H2O (4.7H2O) exhibits a layer substructure that contains the ethylene bridges of the diphosphonate ligands and are linked through corner-sharing octahedral {VO6} sites. The connectivity requirements provide large channels that enclose readily removed water of crystallization. The structure of [H3O][V3F2(H2O)2{O3P(CH2)2PO3}2].3.5H2O (5.3.5H2O) is also 3D. Because of the similiarity with 4.7H2O, it exhibits V/P/O/F layers that include the organic tethers of the diphosphonates and are linked through corner-sharing {VO6} octahedra. In contrast to the network substructure of 4.7H2O, which contains binuclear and trinuclear vanadium clusters, the layers of 5.3.5 H2O are constructed from chains of corner-sharing {VO4F2} octahedra. Thermal studies of the open framework materials 4 and 5 reveal that incorporation of fluoride into the inorganic substructures provides robust scaffoldings that retain their crystallinity to 450 degrees C and above. In the case of 4, dehydration does not change the powder X-ray diffraction pattern of the material, which remains substantially unchanged to 450 degrees C. In the case of 5, there are two dehydration steps, that is, the higher temperature process associated with loss of coordinated water. This second dehydration results in structural changes as monitored by powder X-ray diffraction, but this new phase is retained to ca. 450 degrees C. The materials of this study exhibit a range of reduced oxidation states: 1 is mixed valence V(IV)/V(III) while 2 and 4.7H(2)O are exclusively V(IV) and 3 and 5.3.5H2O are exclusively V(III). These oxidation states are reflected in the magnetic properties of the materials. The paramagnetism of 1 arises from the presence of V(III) and V(IV) sites and conforms to the Curie-Weiss law with C = 2.38 em K/(Oe mol) and = -66 K with mu(eff) (300 K) = 4.33 mu(B). Compounds 3-5 exhibit Curie-Weiss law dependence of magnetism on temperature with mu(eff) (300 K) = 5.45 mu(B) for 3 (six V(III) sites), mu(eff) = 4.60 mu(B) for 4 (seven V(IV) sites) and mu(eff) = 4.13 mu(B) for 5 (two V(III) sites). Compound 2 exhibits antiferromagnetic interactions, and the magnetism may be described in terms of the Heisenberg linear antiferromagnetic chain model for V(IV). The effective magnetic moment at 300 K is 2.77 mu(B) (two V(IV) sites).  相似文献   

5.
A new molybdenum phosphate [Zn(Mov6P4O31H10)2(C4H14N3)2]·2C4H13N3·8H2O 1 (C4H13N3 = diethylenetriamine) has been synthesized under hydrothermal condition. Single-crystal X-ray diffraction reveals that compound 1 crystallizes in the monoclinic, space group P21/n, a =13.1679(3), b = 22.1240(6), c = 13.6146(3) (A), β = 103.4847(7)°, V = 3856.95(16) (A)3,C16H90N12O70P8ZnMo12, Mr = 3035.41, Z = 2, Dc = 2.614 g/cm3, μ = 2.483 mm-1, F(000) = 2968, S = 1.014, the final R = 0.0196 and wR = 0.0506 for 7486 observed reflections (I > 2σ(Ⅰ)). Compound 1 consists of two identical rings of six edge-sharing MoO6 octahedra interconnected by one ZnO6 octahedron, whereas the PO4 tetrahedra which share their apices with the MoO6 octahedra are only located on one side of each Mo6 ring. The 2-charge of polyanion [Zn(Mov6P4O31H10)2]2- unit is compensated in the crystal by two mono-protonated diethylenetriamines (C4H14N3)+. By hydrogen bonding interactions the polyanion of compound 1 is interconnected to form pseudo three dimensional molybdophosphate. Other characterizations by elemental analyses, IR spectrum and fluorescent spectrum are also described.  相似文献   

6.
The hydrothermal chemistry of the CsVO(3)/methylenediphosphonate system was investigated. Variations in reaction temperatures, heating times, and stoichiometries of reactants resulted in the isolation of mononuclear, one-, two-, and three-dimensional species: Cs[VO(HO(3)PCH(2)PO(3)H)(2)(H(2)O)] (1), Cs[VO(HO(3)PCH(2)PO(3))] (2), Cs[(VO)(2)V (O(3)PCH(2)PO(3))(2)(H(2)O)(2)] (3), and [V(HO(3)PCH(2)PO(3))(H(2)O)] (4), respectively. The structure of the anion of 1 consists of isolated V(IV) octahedra. Phase 2 adopts a chain structure constructed from corner-sharing V(IV) octahedra, forming infinite {-V=OV=O-} linkages. The layer structure of 3 contains trinuclear units of corner-sharing {VO(6)} octahedra with the central V site in the III oxidation state and V(IV) centers at the extremities of the cluster. The diphosphonate ligands serve to link neighboring trinuclear motifs into a layer structure three octahedra in depth. The Cs(+) cations occupy cavities within the layers, rather than the more common interlamellar positions. The structure of 4 consists of isolated {V(III)O(6)} octahedra linked by diphosphonate groups into a three-dimensional framework. Crystal data: for 1, CH(6)O(7)P(2)V(0.5)Cs, monoclinic C2, a = 10.991(2) ?, b = 10.161(2) ?, c = 7.445(1) ?, beta = 92.97(3) degrees, Z = 4; for 2, CH(3)O(7)P(2)VCs, monoclinic C2, a = 10.212(2) ?, b = 10.556(2) ?, c = 14.699(3) ?, beta = 94.57(2) degrees, Z = 8; for 3, C(2)H(8)O(16)P(4)V(3)Cs, monoclinic C2/m, a = 9.724(2) ?, b = 8.136(2) ?, c = 10.268(2) ?, beta = 103.75(3) degrees, Z = 2; for 4, CH(5)O(7)P(2)V, monoclinic P2(1)()/n, a = 5.341(1) ?, b = 11.516(2) ?, c = 10.558(2) ?, beta = 99.89(1) degrees, Z = 4.  相似文献   

7.
The hydrothermal reaction of Na2MoO4·2H2O, SmCl3 in acidified H2O/CH3CN solution gives rise to the title compound as colorless needle crystals, which was characterized by elemental analysis, IR and X-ray single-crystal diffraction techniques. Crystallographic data: Orthorhombic, Pnma, H3Mo3NaO11, Mr. = 489.83, a = 8.411(2), b = 7.566(2), c = 14.359(3) A, V= 913.8(3) A3, Z = 4, De = 3.560 g·cm-3,μ = 4.148 mm-1, F(000) = 912, the final R = 0.0649 and wR = 0.1569 for 1885 observed reflections with I ≥ 2σ (I). The title compound consists of infinite chains built up by distorted {MOO6} octahedra via edge sharing, which are further connected into a three-dimensional framework by sodium ions and protoned water molecules.  相似文献   

8.
[C6N2H18]2[Mo5O15(HPO4)2]·H2O的水热合成与结构表征   总被引:6,自引:0,他引:6  
通过水热法合成了一个新化合物[C6N2H18]2[Mo5O15(HPO4)2]·H2O,并通过IR光谱、ICP、元素分析、差热与热重分析和X射线单晶衍射分析等手段进行了表征.结果表明,晶体属三方晶系,P3(2)21空间群,a=1.1231(1)nm,c=2.2802(5)nm,V=2.4911(7)nm3,Dx=2.835Mg/m3,Z=6,最后的一致性因子R=0.0227,wR=0.0675.阴离子中Mo5O15构成一环状结构,2个HPO4一个连在环的下方,一个连在环的上方,形成类似于“飞碟”状的结构,阳离子为2个质子化的四甲基乙二胺.  相似文献   

9.
The hydrothermal reactions of a vanadium source, an appropriate diphosphonate ligand, and water in the presence of HF provide a series of compounds with neutral V-P-O networks as the recurring structural motif. When the {O3P(CH2)(n)PO3}4- diphosphonate tether length n is 2-5, metal-oxide hybrids of type 1, [V2O2(H2O){O3P(CH2)(n)PO3}] x xH2O, are isolated. The type 1 oxides exhibit the prototypical three-dimensional (3-D) "pillared" layer architecture. When n is increased to 6-8, the two-dimensional (2-D) "pillared" slab structure of the type 2 oxides [V2O2(H2O)4{O3P(CH2)6PO3}] is encountered. Further lengthening of the spacer to n = 9 provides another 3-D structure, type 3, constructed from the condensation of pillared slabs to give V-P-O double layers as the network substructure. When organic cations are introduced to provide charge balance for anionic V-P-O networks, oxides of types 4-7 are observed. For spacer length n = 3, a range of organodiammonium cations are accommodated by the same 3-D "pillared" layer oxovanadium diphosphonate framework in the type 4 materials [H3N(CH2)(n)NH3][V4O4(OH)2 {O3P(CH)3PO3}2] x xH2O [n = 2, x = 6 (4a); n = 3, x = 3 (4b); n = 4, x = 2 (4c); n = 5, x = 1 (4d); n = 6, x = 0.5 (4e); n = 7, x = 0 (4f)] and [H3NR]y[V4O4(OH)2 {O3P(CH)3PO3}2] x xH2O [R = -CH2(NH3)CH2CH3, y = 1, x = 0 (4g); R = -CH3, n = 2, x = 3 (4h); R = -CH2CH3, y = 2, x = 1 (4i); R = -CH2CH2CH3, y = 2, x = 0 (4j); cation = [H2N(CH2CH3)2], y = 2, x = 0 (4k)]. These oxides exhibit two distinct interlamellar domains, one occupied by the cations and the second by water of crystallization. Furthermore, as the length of the cation increases, the organodiammonium component spills over into the hydrophilic domain to displace the water of crystallization. When the diphosphonate tether length is increased to n = 5, structure type 5, [H3N(CH2)2NH3][V4O4(OH)2(H2O){O3P(CH2)5PO3}2] x H2O, is obtained. This oxide possesses a 2-D "pillared" network or slab structure, similar in gross profile to that of type 2 oxides and with the cations occupying the interlamellar domain. In contrast, shortening the diphosphonate tether length to n = 2 results in the 3-D oxovanadium organophosphonate structure of the type 7 oxide [H3N(CH2)5NH3][V3O3{O3P(CH2)2PO3}2]. The ethylenediphosphonate ligand does not pillar V-P-O networks in this instance but rather chelates to a vanadium center in the construction of complex polyhedral connectivity of 7. Substitution of piperazinium cations for the simple alkyl chains of types 4, 5, and 7 provides the 2-D pillared layer structure of the type 6 oxides, [H2N(CH2CH2)NH2][V2O2{O3P(CH)(n)PO3H}2] [n = 2 (6a); n = 4 (6b); n = 6 (6c)]. The structural diversity of the system is reflected in the magnetic properties and thermal behavior of the oxides, which are also discussed.  相似文献   

10.
本文报道了一个新的有机双膦酸铜化合物Cu3{(C5NH11)C(OH)(PO3)2}2(H2O)4·4H2O(1)的合成及结构。该化合物呈梯子型双链结构,由Cu(1)O5四方锥体和Cu(2)O6八面体通过{PO3C}四面体以共顶点方式连接而成。相邻的双链以几乎相互垂直的方式堆积,通过氢键作用形成了具有孔道的三维超分子网络结构,晶格水分子填充其中。磁性研究表明在铜离子间存在反铁磁相互作用。  相似文献   

11.
Cao DK  Li YZ  Song Y  Zheng LM 《Inorganic chemistry》2005,44(10):3599-3604
Based on the [hydroxy(4-pyridyl)methyl]phosphonate ligand, three compounds with formula Ni{(4-C(5)H(4)N)CH(OH)PO(3)}(H(2)O) (1), Cd{(4-C(5)H(4)N)CH(OH)PO(3)}(H(2)O) (2), and Gd{(4-C(5)H(4)N)CH(OH)P(OH)O(2)}(3).6H(2)O (3) have been synthesized under hydrothermal conditions. The crystal data for 1 are as follows: orthorhombic, space group Pbca, a = 8.7980(13) A, b = 10.1982(15) A, and c = 17.945(3) A. For 2 the crystal data are as follows: monoclinic, space group C2/c, a = 23.344(6) Angstroms, b = 5.2745(14) Angstroms, c = 16.571(4) Angstroms, and beta = 121.576(4) degrees. The crystal data for 3 are as follows: rhombohedral, space group R, a = 22.2714(16) Angstroms, b = 22.2714(16) Angstroms, and c = 9.8838(11) Angstroms. Compound 1 adopts a three-dimensional pillared layered structure in which the inorganic layers made up of corner-sharing {NiO(5)N} octahedra and {CPO(3)} tetrahedra are connected by pyridyl groups. A two-dimensional layer structure is found in compound 2, which contains alternating inorganic double chains and pyridyl rings. Compound 3 has a one-dimensional chain structure where the Gd atoms are triply bridged by O-P-O linkages. The pyridyl nitrogen atom in 3 remains uncoordinated and is involved in the interchain hydrogen bonds. Magnetic susceptibility studies of 1 and 3 reveal that weak ferromagnetic interactions are mediated between Ni(II) centers in compound 1. For compound 3, the behavior is principally paramagnetic.  相似文献   

12.
1 INTRODUCTION Most materials with nonlinear optical pro- perties and electro-optical applications are either borates or phosphates. LBO(LiB3O5), KTP(KtiO- PO4), BBO(b-BaB2O4) and KDP(KH2PO4) are well- known commercially and extensively used for different optical elements. In recent years, the compounds combined both borate and phosphate groups have been synthesized and structurally characterized with quite different anionic partial structures. In particular, the use of hydrot…  相似文献   

13.
在水热的条件下合成了1个标题的Mo-Ni-O异核簇合物,化学式为H34Ni5Mo12O52 (Mr = 2311.10),用单晶X射线衍射方法测定了它的结构,该晶体属四方晶系,I41/amd空间群,晶胞参数为a = 15.319(2),c = 30.645(3) ,V = 7191.2(16) 3,Z = 4,Dc = 2.135 g/cm3,μ= 3.369 mm-1, F(000) = 4376, 1036个可观察衍射点(I > 2s(I)),最终结构偏离因子R = 0.0560,wR = 0.1632,S = 1.002。该化合物簇阴离子笼中心是Ni2+,由12个MoO6八面体和4个NiO6八面体通过共角和共边构成。  相似文献   

14.
Hydrothermal reactions of bis(benzimidazol-2-ylmethyl)imino(methylenephosphonic acid) {[(C(7)H(5)N(2))CH(2)]2NCH(2)PO(3)H(2), bbimpH2} with metal salts result in four new compounds, namely, Mn2{[(C(7)H(5)N(2))CH2]2NCH(2)PO(3)}2(H2O)2.2H2O (1), Cd2{[(C(7)H(5)N(2))CH2]2NCH(2)PO(3)}2.2H2O (2), Fe2{[(C(7)H(5)N(2))CH2]2NCH(2)PO(3)}2.H2O (3), and CuI(2){[(C(7)H(5)N(2))CH2]2NCH(2)P(OH)O2}2 (4). Compounds 1 and 2 have dinuclear structures in which two {MN(3)O(3)} octahedra are linked through edge sharing. In compound 3, a chain structure is observed where the {FeN(3)O(2)} trigonal bipyramids are linked by {CPO(3)} tetrahedra through corner-sharing. The structure of compound 4 is unique. The monovalent Cu(I) ions are connected by the imidazole nitrogen atoms from the bbimp(2-) ligands forming a 16-member metallomacrocycle. These metallomacrocycles are further connected by the phosphonate oxygen atoms, leading to a two-dimensional net containing 16- and 32-member rings. Magnetic studies of 1 and 3 reveal that weak ferromagnetic interactions are mediated between magnetic centers in compound 1, while antiferromagnetic interactions were observed in compound 3.  相似文献   

15.
研究了一种可循环并且环境友好的催化体系:[π-C5H5N(CH2)15CH3]3[PMoW3O24]/过氧化氢/乙酸乙酯/烯烃.此体系不仅可以催化烯烃的环氧化反应,而且避免了对含氯溶剂的使用.反应在过氧化氢/乙酸乙酯的两相体系中进行,可以将多种烯烃转化为相应的环氧化物,且产率较高.此催化剂具有反应控制相转移的特征,反应结束后可以回收再利用.采用Raman,IR,^31P MAS NMR和^31P NMR等手段对新鲜及重复使用过的催化剂进行表征.结果表明:新鲜催化剂[π-C5H5N(CH2)15CH3]3[PMoW3O24]是一种混合物,含有多种过氧磷钼钨酸盐,如{PO4[MoO(O2)2]4}^3-,[(PO4){Mo3WO20}]^3-,[(PO4){Mo2W2O20}]^3-,[(PO4){MoW3O20}]^3-和{PO4[WO(O2)2]4}^3-.当过氧化氢被完全消耗后,这些小的活性物种就会聚合成具有混合多原子的Keggin型杂多阴离子,形成M-Ob—M(M=W或Mo)和M-Oc-M键.  相似文献   

16.
The hydrothermal reactions of a Cu(II) starting material, a molybdate source, 2,2'-bipyridine or terpyridine, and the appropriate alkyldiphosphonate ligand yield two series of bimetallic organophosphonate hybrid materials of the general types [Cu(n)(bpy)(m)Mo(x)O(y)(H(2)O)(p)[O(3)P(CH(2))(n)PO(3)](z)] and [Cu(n)(terpy)(m)Mo(x)O(y)(H(2)O)(p)[O(3)P(CH(2))(n)PO(3)](z)]. The bipyridyl series includes the one-dimensional materials [Cu(bpy)(MoO(2))(H(2)O)(O(3)PCH(2)PO(3))] (1) and [[Cu(bpy)(2)][Cu(bpy)(H(2)O)](Mo(5)O(15))(O(3)PCH(2)CH(2)CH(2)CH(2)PO(3))].H(2)O (5.H(2)O) and the two-dimensional hybrids [Cu(bpy)(Mo(2)O(5))(H(2)O)(O(3)PCH(2)PO(3))].H(2)O (2.H(2)O), [[Cu(bpy)](2)(Mo(4)O(12))(H(2)O)(2)(O(3)PCH(2)CH(2)PO(3))].2H(2)O (3.2H(2)O), and [Cu(bpy)(Mo(2)O(5))(O(3)PCH(2)CH(2)CH(2)PO(3))](4). The terpyridyl series is represented by the one-dimensional [[Cu(terpy)(H(2)O)](2)(Mo(5)O(15))(O(3)PCH(2)CH(2)PO(3))].3H(2)O (7.3H(2)O) and the two-dimensional composite materials [Cu(terpy)(Mo(2)O(5))(O(3)PCH(2)PO(3))] (6) and [[Cu(terpy)](2)(Mo(5)O(15))(O(3)PCH(2)CH(2)CH(2)PO(3))] (8). The structures exhibit a variety of molybdate building blocks including isolated [MoO(6)] octahedra in 1, binuclear subunits in 2, 4, and 6, tetranuclear embedded clusters in 3, and the prototypical [Mo(5)O(15)(O(3)PR)(2)](4-) cluster type in 5, 7, and 8. These latter materials exemplify the building block approach to the preparation of extended structures.  相似文献   

17.
A nickel-1,10-phenanthroline complex supported on an octamolybdate, [{Ni(phen)2}2(x- Mo8O26)], has been hydrothermally synthesized with MoO3, H2MoO4, Ni(OAc)2· 6H2O and 1,10-phenathroline (1,10-phen) as raw materials. The crystals of the compound belong to monoclinic P21/n space group, a = 1.2952(2), b = 1.6659(10), c = 1.3956(12) nm, b =106.273(8)°, V = 2.8906(5) nm3, Z = 2. 5604 observable reflections (I >2s(I)) were used for structure resolution and refinements to converge to final R1 = 0.0414, wR2 = 0.0815. The result of structure determination shows that the compound contains octamolybdate possessing a novel structure type (named as x-isomer). The feature of x-[Mo8O26]4- is that it is composed of Mo6O6 ring and two MoO6 octahedra located at cap positions on opposite faces. The Mo6O6 ring contains two octahedral and four trigonal-bipyramidal MoVI atoms. Each x-[Mo8O26]4- unit is bonded with two [Ni(phen)2]2+ through terminal oxygen atoms of octahedral and neighbouring trigonal-bipyramidal Mo atom in the Mo6O6 ring. IR and UV-Vis spectra of the compound were measured and its electronic structure was studied by EHMO method.  相似文献   

18.
Two manganese phosphonates Mn3(4-piH)2(H2O)3·H2O (1) and Mn5(4-piH)2(4-piH2)2(phen)2(H2O)4 (2) (4-piH4 = 4-phosphonoisophthalic acid, phen = 1,10-phenanthroline) have been synthesized under hydrothermal conditions in the presence of organic co-ligand. Both compounds exhibit layer structures but with different topologies. In compound 1, a complicated "ladder-like" chain of {Mn3O3}O2 which contains three- and six-member rings made up of triangular shaped {Mn3O3} trimers is found. The chains are linked by the PO3C groups to form an inorganic layer. The phenyl and protonated carboxylate groups are pendent between the layers with extensive hydrogen bonds. In compound 2, tetramers of {Mn4O6} are connected by the {MnO6} octahedra through corner-sharing to form an infinite chain, which is further bridged by 4-piH3- ligands into a thick hybrid layer. Magnetic measurements reveal that antiferromagnetic interactions are dominant in both compounds. Metamag- netism is observed in compound 1 at low temperature, while no long range ordering is found in compound 2 down to 1.8 K.  相似文献   

19.
摘要 藉助模拟强度精修将九个镧系络合物晶体结构的空间群作了修正 .( 1) NaN[Nd(DMSO)5(H2O)3]Cl3· 3H2O从 P1修正为 P;( 2) Er(ClO4)3· 6(CH3)2NC(O)N(CH3)2从 P修正为 R;( 3) Nd(O3SCF3)3· DMF· 6H2O从 P1修正为 R3m;(4)[NaNCCH3][Nd{S2CN(CH2CH3)2}4]从 P修正为 C 2/c;(5)[(CH3)2NCS2]3La· 2DMSO从 Cc修正为 C 2/c;( 6) Yb(C9H7)2· 2THF从 Cc修正为 C 2/c;( 7) [(C6H5)3Ge]2Yb· 4THF从 P21修正为 P 2;(8)TlPr(C36H44N4)2从 Pna2,修正为 Pnma;(9)[CuLaSm(C4O4)4(H2O)16]· 2H2O从 P2修正为 P2.( 8)、( 9)两个络合物结构从非心修正到有心时,不仅改进了键长与键角值,而且影响到分子结构特征的描述 .  相似文献   

20.
Reactivity studies of oxo-Mo(IV) complexes, Tp(iPr)MoO{2-OC(6)H(4)C(O)R-κ(2)O,O'} (R = Me, Et, OMe, OEt, OPh, NHPh), containing chelated hydrogen-bond donor/acceptor phenolate ligands are reported. Hydrolysis/oxidation of Tp(iPr)MoO(2-OC(6)H(4)CO(2)Ph-κ(2)O,O') in the presence of methanol yields tetranuclear [Tp(iPr)MoO(μ-O)(2)MoO](2)(μ-OMe)(2) (1), while condensation of Tp(iPr)MoO{2-OC(6)H(4)C(O)Me-κ(2)O,O'} and methylamine gives the chelated iminophenolate complex, Tp(iPr)MoO{2-OC(6)H(4)C(Me)NMe-κ(2)O,N} (2), rather than the aqua complex, Tp(iPr)MoO{2-OC(6)H(4)C(Me)NMe-κO}(OH(2)). The oxo-Mo(IV) complexes are readily oxidized by dioxygen or hydrogen peroxide to the corresponding cis-dioxo-Mo(VI) complexes, Tp(iPr)MoO(2){2-OC(6)H(4)C(O)R}; in addition, suitable one-electron oxidants, e.g., [FeCp(2)]BF(4) and [N(C(6)H(4)Br)(3)][SbCl(6)], oxidize the complexes to their EPR-active (g(iso) ≈ 1.942) molybdenyl counterparts (3, 4). Molybdenyl complexes such as Tp(iPr)MoOCl{2-OC(6)H(4)C(O)R} (5) and Tp(iPr)MoOCl(2) also form when the complexes react with chlorinated solvents. The ester derivatives (R = OMe, OEt, OPh) react with propylene sulfide to form cis-oxosulfido-Mo(VI) complexes, Tp(iPr)MoOS{2-OC(6)H(4)C(O)R}, that crystallize as dimeric μ-disulfido-Mo(V) species, [Tp(iPr)MoO{2-OC(6)H(4)C(O)R}](2)(μ-S(2)) (6-8). The crystal structures of [Tp(iPr)MoO(μ-O)(2)MoO](2)(μ-OMe)(2), Tp(iPr)MoO{2-OC(6)H(4)C(Me)NMe}, Tp(iPr)MoOCl{2-OC(6)H(4)C(O)NHPh}·{2-HOC(6)H(4)C(O)NHPh}, and [Tp(iPr)MoO{2-OC(6)H(4)C(O)R}](2)(μ-S(2)) (R = OMe, OEt) are reported.  相似文献   

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