Year: 2026
Type: article
Abstract: The title compound, rubidium cobalt iron bis(phosphate), was synthesized by the solid-state method under atmospheric conditions. This phosphate crystallizes with trigonal symmetry in space group P 3 m 1 and all atoms lie on special crystallographic positions. In this structure, the Co II O 4 tetrahedra alternate with one of the two types of PO 4 tetrahedra, sharing the vertices of their bases and extending along the a - and b -axis directions to form a first tetrahedral layer, lying parallel to the (001) plane. The same alternation is observed between the Fe III O 4 tetrahedra and the other PO 4 tetrahedra, leading to the formation of a second layer also lying parallel to the (001) plane. In the first layer, all tetrahedra are oriented downwards, while in the second, they are oriented upwards with respect to the c axis. The interconnection between these two layers is ensured by the sharing of the vertices of the CoO 4 and PO 4 tetrahedra, as well as the vertex of the FeO 4 tetrahedra, with those of the other PO 4 tetrahedra. The stacking of these two layers leads to the formation of [CoFeP 2 O 8 ] − ∞ double layers lying parallel to the (001) plane and creates hexagonal tunnels running parallel to the c -axis direction. The Rb + cations are located at the intersection of the tunnels with the interlayer space, thus forming a plane lying perpendicular to the c -axis direction, sandwiched between the double layers. In this structure, each rubidium atom exhibits a coordination number of twelve, whereas in the similar structure of KMgFe(PO 4 ) 2 , which has monoclinic symmetry, the potassium cation is surrounded by eight oxygen atoms.
Language: English
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $500
OpenAlex ID: W7218513574