Alhakmi Ghaleb, Assani Abderrazzak, Saadi Mohamed, El Ammari Lahcen
Laboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Battouta, BP 1014, Rabat, Morocco.
Acta Crystallogr Sect E Struct Rep Online. 2013 Jun 22;69(Pt 7):i40. doi: 10.1107/S1600536813016504. eCollection 2013.
The title compound, lead trimanganese tris(orthophosphate), has been synthesized by hydro-thermal methods. In this structure, only two O atoms are in general positions and all others atoms are in the special positions of the Imma space group. Indeed, the atoms in the Wyckoff positions are namely: Pb1 and P1 on 4e (mm2); Mn1 on 4b (2/m); Mn2 and P2 on 8g (2); O1 on 8h (m); O2 on 8i (m). The crystal structure can be viewed as a three-dimensional network of corner- and edge-sharing PO4 tetra-hedra and MnO6 octa-hedra, building two types of chains running along the b axis. The first is an infinite linear chain, formed by alternating Mn(III)O6 octa-hedra and PO4 tetra-hedra which share one vertex. The second chain is built up from two adjacent edge-sharing octa-hedra (Mn(II) 2O10 dimers) whose ends are linked to two PO4 tetra-hedra by a common edge. These chains are linked together by common vertices of polyhedra in such a way as to form porous layers parallel to (001). These sheets are bonded by the first linear chains, leading to the appearance of two types of tunnels, one propagating along the a axis and the other along b. The Pb(II) ions are located within the inter-sections of the tunnels with eight neighbouring O atoms in form of a trigonal prism that is capped by two O atoms on one side. The three-dimensional framework of this structure is compared with similar phosphates such as Ag2Co3(HPO4)(PO4)2 and Ag2Ni3(HPO4)(PO4)2.
标题化合物三锰酸铅（III）三（正磷酸）已通过水热法合成。在该结构中，只有两个O原子处于一般位置，所有其他原子都处于Imma空间群的特殊位置。实际上，在Wyckoff位置的原子分别为：位于4e（mm2）的Pb1和P1；位于4b（2/m）的Mn1；位于8g（2）的Mn2和P2；位于8h（m）的O1；位于8i（m）的O2。晶体结构可视为由角共享和边共享的PO4四面体以及MnO6八面体组成的三维网络，形成了沿b轴延伸的两种类型的链。第一种是无限线性链，由交替的Mn(III)O6八面体和PO4四面体共享一个顶点形成。第二条链由两个相邻的边共享八面体（Mn(II)2O10二聚体）组成，其末端通过一条公共边与两个PO4四面体相连。这些链通过多面体的公共顶点连接在一起，形成平行于(001)的多孔层。这些片层由第一条线性链连接，导致出现两种类型的隧道，一种沿a轴传播，另一种沿b轴传播。Pb(II)离子位于隧道交叉处，周围有八个相邻的O原子，呈三角棱柱形式，一侧由两个O原子封顶。该结构的三维框架与类似的磷酸盐如Ag2Co3(HPO4)(PO4)2和Ag2Ni3(HPO4)(PO4)2进行了比较。
