Spheniscidite, a synthetic iron phosphate mineral has been synthesized by hydrothermal methods. The material is isotypic with another iron phosphate mineral, leucophosphite. Spheniscidite crystallizes in the monoclinic spacegroupP2₁/n. (a=9·845(1),b=9·771(3),c=9·897(1),β=102·9°,V=928·5(1),Z=4,M=372·2,d_calc=2·02 g cm⁻³ andR=0·02). The structure consists of a network of FeO₆ octahedra vertex-linked with PO₄ tetrahedra forming 8-membered one-dimensional channels in which the NH₄⁺ ions and H₂O molecules are located. The material exhibits reversible dehydration and good adsorption behaviour. Magnetic susceptibility measurements indicate that the solid orders antiferromagnetically.

A new iron fluorophosphate of the composition, [C₆N₄H₂₁] [Fe₂F₂(HPO₄)₃][H₂PO₄]·2H₂O,I has been prepared by the hydrothermal route. This compound contains iron fluorophosphate layers and the H₂PO₄^- anions are present in the interlayer space along with the protonated amine and water molecules. The compound crystallizes in the monoclinic space group P2₁/c.(a = 13.4422(10) Å,b = 9.7320(10) Å, c = 18.3123(3) Å, β= 92.1480°,V= 2393.92(5) ų, Z = 4,M = 719.92,d_calc. = 1.997 g cm^-3, R₁ = 0.03 andwR₂= 0.09).