New open-framework in the uranyl vanadates A3(UO2)7(VO4)5O (A=Li, Ag) with intergrowth structure between A(UO2)4(VO4)3 and A2(UO2)3(VO4)2O
New open-framework in the uranyl vanadates A3(UO2)7(VO4)5O (A=Li, Ag) with intergrowth structure between A(UO2)4(VO4)3 and A2(UO2)3(VO4)2O
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DOI：
10.1016/j.jssc.2008.10.019
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发表时间：
2009-03
影响因子：
3.3
通讯作者：
S. Obbade;C. Renard;F. Abraham
中科院分区：
文献类型：
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作者：
S. Obbade;C. Renard;F. Abraham
新铀酰钒酸盐A3(UO2)7(VO4)5O(M=Li(1)，Na(2)，∞_2[(UO_2)_2(VO_4)_2]_4−和∞_2[(UO_2)_2(VO_4)_3]_5_−由UO_6正方形双金字塔通过VO_4四面体与∞_1[U_(3)O_5-U(4)O_5]_8−无限链交替连接的四方结构结果A轴和b轴以构建三维的铀酰钒酸盐排列。值得注意的是，类似的∞[UO_5]_4−链仅由A2(UO_2)_3(VO_4)_2O中的S片层和A(UO_2)_4(VO_4)_3中的D-型片层连接，因此A_3(U_2)_7(VO_4)_5O似乎是两个已报道的系列之间的共生结构。在三维排列中形成的相互垂直的通道中，一价离子的迁移率与格位的占有率和Na、Ag或Li占据的不同格位的几何形状有关。晶体数据：293K，配备4K ccd探测器的Bruker X8-APEX2 X射线衍射仪，MoKα，λ=0.71073？，四方对称，空间群P4‘m2，Z=1，在F2的基础上进行全矩阵最小二乘精修；1，a=7.2794(9)？，c=14.514(4)？，r1=0.021，wr2=0.048，62个参数，782个独立反射，i⩾2σ(I)；3，a=7.2373(3)？，c=14.7973(15)？，r1=0.041，wr2=0.085，60个参数，1066个独立反射，i⩾2σ(I)。
New uranyl vanadates A3(UO2)7(VO4)5O (M=Li (1), Na (2), Ag (3)) have been synthesized by solid-state reaction and their structures determined from single-crystal X-ray diffraction data for 1 and 3. The tetragonal structure results of an alternation of two types of sheets denoted S for∞2[UO2(VO4)2]4−and D for∞2[(UO2)2(VO4)3]5−built from UO6square bipyramids and connected through VO4tetrahedra to∞1[U(3)O5-U(4)O5]8−infinite chains of edge-shared U(3)O7and U(4)O7pentagonal bipyramids alternatively parallel to a- and b-axis to construct a three-dimensional uranyl vanadate arrangement. It is noticeable that similar∞[UO5]4−chains are connected only by S-type sheets in A2(UO2)3(VO4)2O and by D-type sheets in A(UO2)4(VO4)3, thus A3(UO2)7(VO4)5O appears as an intergrowth structure between the two previously reported series. The mobility of the monovalent ion in the mutually perpendicular channels created in the three-dimensional arrangement is correlated to the occupation rate of the sites and by the geometry of the different sites occupied by either Na, Ag or Li. Crystallographic data: 293K, Bruker X8-APEX2 X-ray diffractometer equipped with a 4K CCD detector, MoKα, λ=0.71073Å, tetragonal symmetry, space group P4¯m2, Z=1, full-matrix least-squares refinement on the basis of F2; 1,a=7.2794(9)Å, c=14.514(4)Å, R1=0.021 and wR2=0.048 for 62 parameters with 782 independent reflections with I⩾2σ(I); 3, a=7.2373(3)Å, c=14.7973(15)Å, R1=0.041 and wR2=0.085 for 60 parameters with 1066 independent reflections with I⩾2σ(I).