THE FIRST ORGANICALLY TEMPLATED LAYERED IRON PHOSPHATE - HYDROTHERMAL SYNTHESIS, STRUCTURE, MAGNETIC PROPERTIES, AND THE MOSSBAUER SPECTRUM OF [H3NCH2CH2NH3](0.5)[FE(OH)(PO4)]

摘要

The first organically templated, layered iron phosphate [H3NCH2CH2NH3](0.5)[Fe(OH)(PO4)], 1, has been prepared and characterized via single crystal X-ray diffraction, variable temperature magnetic susceptibility measurements, and Mossbauer spectroscopy. Phosphate 1 is synthesized from the hydrothermal reaction of FeCI3, H3PO4, ethylenediamine, and H2O in the mole ratio 1:3.6:4.2:444 for 64 h at 160 degrees C and exhibits a layered structure consisting of infinite chains of edge-sharing {FeO6} octahedra linked into finite 2-D sheets by {PO4} tetrahedra that possess terminal P=O groups which protrude into the interlamellar space. The infinite edge-sharing chains display a pairwise puckering resulting from the presence of trans mu(2)-OH groups arranged in a zig-zag fashion along the chain. The charge compensating ethylenediammonium cations contact both adjacent layers via an elaborate and complicated hydrogen bonded network. Crystal data for 1: FePO5NCH6, monoclinic, space group P2(1)/c, a = 4.5010(7) Angstrom, b = 6.114(1) Angstrom, c = 18.460(3) Angstrom, beta = 94.59(1)degrees, V = 56.4(1) Angstrom, Z = 2, d(calc) = 2.608 g . cm(-3); 1650 reflections, R = 0.049. Variable temperature Mossbauer data, de magnetization, and ac susceptibility measurements show that 1 undergoes a transition to a weak ferromagnetic state near 30 K. (C) 1996 Academic Press, Inc. [References: 33]