Synthesis and structure of the first three-legged low-dimensional iron phosphate, [H3N(CH2)(3)NH2(CH2)(2)NH2(CH2)(3)NH3][Fe3F6(HPO4)(2)(PO4)]center dot 3H(2)O

摘要

A hydrothermal reaction of iron acetylacetonate, phosphoric acid, HF, N,N'-bis(3-aminopropyl)ethylenediamine and water at 150degreesC gave rise to a new iron phosphate, [H3N(CH2)(3)NH2(CH2)(2)NH2(CH2)(3)NH3][Fe3F6(HPO4)(2)(PO4)](.) 3H(2)O (I). The structure consists of Fe(1)O4F2, Fe(2)O3F3 octahedral and P(1)O-3(OH) and P(2)O-4 tetrahedral building units connected through their vertices to form fragments of tancoite-type units. The tancoite-type units are linked through the phosphate tetrahedra forming an unusual iron phosphate with a hitherto unknown low-dimensional structure with three-iron center. Magnetic studies indicate a complex behavior at low temperature and the high-temperature data (150 - 300 K) has a Curie-Weiss behavior. The calculated room temperature magnetic moment is 6 mu(B) per Fe atom, and the Neel temperature, T-N = 46K. Crystal data: orthorhombic, space group = I2(1)2(1)2(1) (no. 24), a = 9.9042(11), b = 12.8865(14), c = 19.783(2) Angstrom, U = 2524.9(5), Z = 4. [References: 12]