The preparation and structural characterization of three new iron phosphates with general formula Rb3M3Fe5(PO4)8 (M = Mn, Co, Ni) labeled: I, II and III respectively, are reported. Single crystals X-ray diffraction reveals that these compounds crystallize in an original structure, which adopts the monoclinic system with space group C2/c. The unit cell parameters are: a = 19.945(1) Å; b = 14.935(7); c = 9.995(1) Å; β = 119.10(3)° for I, a = 19.826(1) Å; b = 14.948(1); c = 9.927(1) Å; β = 117.14(1) ° for II and for III a = 19.792(2) Å; b = 14.833(2); c = 9.908(2) Å; β = 119.28(2)°. The structures consist of MO6 and (M,Fe)O6 octahedra, linked through common edges to form [M2(M,Fe)2O16]∞ crossing chains running along the [1 1 2] and [1 − 1 2] directions. These chains are interconnected by the FeO6 octahedra and PO4 tetrahedra, generating a 3D framework with intersecting tunnels where the Rb+ cations are located.Graphical AbstractThis paper report the synthesis and the structural study of three new alkali iron phosphates Rb3M3Fe5(PO4)8 (M = Mn, Co, Ni). A projection of the Rb3M3Fe5(PO4)8 (M = Mn, Co, Ni) structure along the [112] direction.

中文翻译：

---

三种新型磷酸铁 Rb3M3Fe5(PO4)8 (M = Mn, Co, Ni) 的合成及结构性能

报告了三种新型磷酸铁的制备和结构表征，其通式 Rb3M3Fe5(PO4)8（M = Mn、Co、Ni）分别标记为：I、II 和 III。单晶X射线衍射表明这些化合物以原始结构结晶，采用空间群为C2/c的单斜晶系。晶胞参数为：a = 19.945(1) Å；b = 14.935(7); c = 9.995(1) Å；对于 I，β = 119.10(3)°，a = 19.826(1) Å；b = 14.948(1); c = 9.927(1) 埃；β = 117.14(1) ° II 和 III a = 19.792(2) Å；b = 14.833(2); c = 9.908(2) Å；β = 119.28(2)°。结构由 MO6 和 (M,Fe)O6 八面体组成，通过共同边连接形成 [M2(M,Fe)2O16]∞ 交叉链，沿 [1 1 2] 和 [1 − 1 2] 方向运行。这些链通过 FeO6 八面体和 PO4 四面体相互连接，生成具有 Rb+ 阳离子所在的交叉隧道的 3D 框架。图形摘要本文报告了三种新型碱金属磷酸铁 Rb3M3Fe5(PO4)8 (M = Mn, Co, Ni) 的合成和结构研究。Rb3M3Fe5(PO4)8 (M = Mn, Co, Ni) 结构沿 [112] 方向的投影。