Zouihri Hafid, Saadi Mohammed, Jaber Boujemaa, El Ammari Lehcen
Acta Crystallogr Sect E Struct Rep Online. 2011 Jun 1;67(Pt 6):i39. doi: 10.1107/S1600536811019477. Epub 2011 May 28.
The title compound contains infinite one-dimensional BP(2)O(8) borophosphate helical ribbons, built up from alternate BO(4) and PO(4) tetra-hedra arranged around the 6(5) screw axes. The vertex-sharing BO(4) and PO(4) tetra-hedra form a spiral ribbon of four-membered rings in which BO(4) and PO(4) groups alternate. The ribbons are connected through slightly distorted MgO(4)(H(2)O)(2) octa-hedra, in which the four O atoms belong to the phosphate groups. The free threads of the helices are occupied by silver ions, which are in an irregular environment surrounded by six O atoms. The central channels of the helices, running along the c axis, are filled with the water mol-ecules. The structure is stabilized by O-H⋯O hydrogen bonds between the water mol-ecules and O atoms that are part of the helices. The crystal structure of the title compound is isotopic with other analogous borophosphates such as A(I)M(II)(H(2)O)(2)[BP(2)O(8)]·H(2)O, where A(I) = Li, Na, K or NH(4) (+) and M(II) = Mg, Mn, Fe, Co, Ni, Cu, Zn or Cd.
标题化合物包含无限的一维[BP₂O₈]³⁻硼磷酸盐螺旋带，由围绕6₅螺旋轴排列的交替的BO₄和PO₄四面体构成。顶点共享的BO₄和PO₄四面体形成一个四元环的螺旋带，其中BO₄和PO₄基团交替排列。这些带通过略微扭曲的MgO₄(H₂O)₂八面体相连，其中四个O原子属于磷酸基团。螺旋的自由端被银离子占据，银离子处于由六个O原子包围的不规则环境中。沿着c轴延伸的螺旋的中心通道被水分子填充。该结构通过水分子与作为螺旋一部分的O原子之间的O—H⋯O氢键得以稳定。标题化合物的晶体结构与其他类似的硼磷酸盐如A(I)M(II)(H₂O)₂[BP₂O₈]·H₂O同构，其中A(I)=Li、Na、K或NH₄⁺，M(II)=Mg、Mn、Fe、Co、Ni、Cu、Zn或Cd。
