Synthesis and Characterization of a New Ferrimagnetic Mixed-Valent Iron Fluorophosphate [C6N4H21][FeIII3-xFeIIxF2(PO4)(HPO4)2]2 (x ∼ 1.5) with a Layered Structure

Autor: Srinivasan Natarajan, Gerard Ferey, Myriam Riou-Cavellec, Jean-Marc Greneche, Sukhendu Mandal
Rok vydání: 2002
Předmět:
Zdroj: Chemistry of Materials. 14:3751-3757
ISSN: 1520-5002
0897-4756
Popis: The synthesis, structure, and magnetic properties of a mixed valent iron fluorophosphate, [C6N4H21][FeIII3-xFeIIxF2(PO4)(HPO4)2]2 (x ∼ 1.5) has been described. The structure consists of a network of FeO4F2 octahedra and PO4 tetrahedra linked through their vertexes, forming infinite two-dimensional sheets separated by the organic amine molecules, triethylenetetrammonium cations (TETA). A remarkable feature of this structure is the presence of chains of FeII−O−FeII that are connected by FeIII octahedra, forming infinite two-dimensional sheets of Fe−O/F−Fe. This is the first time such linkages have been observed in two-dimensional iron fluorophosphates. Magnetic studies indicate ferrimagnetic behavior with a Curie temperature of Tc = 25 K. Mossbauer studies show mixed occupancies in the FeII sites. Crystal data: M = 567.61, triclinic, space group = P1 (no. 2), a = 6.431(4) A, b = 10.274(5) A, c = 10.439(3) A, α = 80.56(4)°, β = 89.53(2)°, γ = 87.94(4)°, V = 680.0(6) A3, Z = 2, ρ(calc.) = 2.772 g cm-3, μ(Mo...
Databáze: OpenAIRE