A new three-dimensional open-framework iron(III) phosphate, [C2N2H10][Fe2(HPO4)4]

A new open-framework iron(III) phosphate, I, [C2N2H10][Fe-2(HPO4)(4)] has been hydrothermally synthesized in the presence of ethylenediamine (en). The structure is built up from the vertex linkages between the FeO6 octahedra and the PO4 tetrahedra, strictly alternating, forming the three-dimensional architecture. The linkages between the FeO6 and PO4 polyhedra gives rise to ladder-like edge-shared chains, which are connected variously forming two types of channels. The di-protonated en molecules occupy these channels. Crystal data for I, [C2N2H10][Fe4P4O16]: a=9.341(1), b=8.892(1), c=9.480(1) Angstrom, beta=117.6(1)degrees, V=698.1(1) Angstrom(3), space group P2/n (No. 13), Z=2, M=557.7, D-calc=2.65 g cm(-3), MoK alpha(lambda=0.71073 Angstrom), R-1=0.03, wR(2)=0.08 and S=1.10. Magnetic susceptibility studies indicate a predominantly antiferromagnetic interaction with T-N=30 K. (C) 2000 Elsevier Science Ltd. All rights reserved.