Synthesis, structure and magnetic property of a new organo-templated mixed-valent iron(ii, iii) borophosphate†
Abstract
A new layered iron borophosphate (C4N3H16)(C4N3H15)0.5[Fe2B4P7O26(OH)4] (denoted FeBPO-CJ28), with a novel B/P ratio of 4/7 and mixed-valent iron(II, III) was prepared under mild hydrothermal conditions in the presence of (No. 2), a = 8.9568(3) Å, b = 9.8717(3) Å, c = 17.9905(5) Å, α = 102.510(2)°, β = 92.343(2)°, γ = 100.403(2)°, V = 1522.10(8) Å3, and Z = 2). The structure comprises unprecedented anionic double layers 2∞{[Fe2B4P7O26(OH)4]4−} with one-dimensional 8-ring channels along the [110] direction, which are made up of FeO6, BO4, PO4 and HPO4 polyhedral units. Such double layers parallel to the ab plane are connected by inter-layer hydrogen bonds forming the three-dimensional (3D) supramolecular open framework with pseudo 10-ring channels along the [110] direction. Protonated DETA