Spheniscidite, ammonium hydroxide iron phosphate dihydrate, [Fe2(NH4)(
OH)(PO4)2].2H2O, is known as a mineral isotypic with leucophosphite. C
rystals were obtained by hydrothermal synthesis at medium temperature.
The crystal structure determination confirms the leucophosphite struc
ture type and provides detailed localization of the water molecules an
d ammonium cations inside the cavities of the framework.