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21.
Two new gallium phosphates, [NH3(CH2)4NH3][Ga4(PO4)4 (HPO4)] (I) and [NH3(CH2)4NH3][Ga(PO4)(HPO4)] (II), have been synthesized under solvothermal conditions in the presence of 1,4-diaminobutane and their structures determined using room-temperature single-crystal X-ray diffraction data. Compound (I) (Mr=844.90, triclinic, space group P-1, a=9.3619(3), b=10.1158(3) and c=12.6456(5) Å, α=98.485(1), β=107.018(2) and γ=105.424(1)°; V=1070.39 Å3, Z=2, R=3.68% and Rw=4.40% for 2918 observed data [I>3(σ(I))]) consists of GaO4 and PO4 tetrahedra and GaO5 trigonal bipyramids linked to generate an open three-dimensional framework containing 4-, 6-, 8-, and 12-membered rings of alternating Ga- and P-based polyhedra. 1,4-Diaminobutane dications are located in channels bounded by the 12-membered rings in the two-dimensional pore network and are held to the framework by hydrogen bonding. Compound (II) (Mr=350.84, monoclinic, space group P21/c, a=4.8922(1), b=18.3638(6) and c=13.7468(5) Å, β=94.581(1)°; V=1227.76 Å3, Z=4, R=2.95% and Rw=3.37% for 2050 observed data [I>3(σ(I))]) contains chains of edge-sharing 4-membered rings of alternating GaO4 and PO4 tetrahedra constituting a backbone from which hang ‘pendant’ PO3(OH) groups. Hydrogen bonding between the GaPO framework and the diamine dications holds the structure together. A previously reported phase, [NH3(CH2)4NH3][Ga4(PO4)4(HPO4)] (V), structurally related but distinct from its stoichiometric equivalent, (I), has been prepared as a pure phase by this method. Two further materials, [NH3(CH2)5NH3][Ga4(PO4)4(HPO4)] (III) (tricli- nic, lattice parameters from PXD: a=9.3565(4), b=5.0156(2) and c=12.7065(4) Å, α=96.612(3), β=102.747(4) and γ=105.277(3)°) and [NH3(CH2)5NH3][Ga(PO4)(HPO4)] (IV) (Mr=364.86, monoclinic, space group P21/n, a=4.9239(2), b=13.2843(4) and c=19.5339(7) Å, β=96.858(1)°; V=1268.58 Å3, Z=4, R=3.74% and Rw=4.44% for 2224 observed room-temperature data [I>3(σ(I))]), were also prepared under similar conditions in the presence of 1,5-diaminopentane. (III) and (IV) are structurally related to, yet distinct from (I) and (II) respectively.  相似文献   
22.
A new vanadium(Ⅲ) phosphite,V2(HPO3)3(1),was synthesized hydrothermally with V2O5,H3PO3 as reactants,1,6-diaminopropane(1,6-HAD) as the structure-directing agent and characterized by single crystal X-ray diffraction,powder X-ray diffraction,IR spectroscopy,TGA,ICP-AES and elemental analyses.Single-crystal X-ray diffraction analysis reveals that compound 1 crystallized in the P6(3)/m hexagonal space group with the unit-cell parameters:a=0.80436(10) nm,c=0.73972(2) nm,V=0.41447(13) nm3,Z=4.The construction of...  相似文献   
23.
FeCl2与酸性离子液在乙醇中反应制备得到咪唑硫酸铁簇合物[HMIM]2[Fe2O(SO43(DMSO)2]·0.5DMSO(1)和[HPIM]4[Fe4O2(SO46(DMSO)4]·2MeCN(2),该类簇合物为四核铁簇Fe4(O)2(SO46(DMSO)4结构,4个Fe原子通过中心μ3-O桥、硫酸根上的μ2-O和μ3-O桥连接,形成共平面结构,中间的四核铁簇为-4价,4个质子化的咪唑正离子起电荷平衡作用。该簇合物的晶体结构属于三斜晶系中的P1空间群。变温磁化率测试表明该簇合物具有强的反铁磁性。但在类似的反应条件下,FeCl3在酸性离子液反应没有得到类似的簇合物,而是得到DMSO配合物[FeCl2(DMSO)4][EtSO4]·DMSO(3)。  相似文献   
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