New iron(III) nitrate hydrates: Fe(NO3)3•xH2O with x = 4, 5 and 6

Crystals of the title compounds were grown from their hydrous melts or solutions. The crystal structure of iron(III) trinitrate hexahydrate {hexaaquairon(III) trinitrate, Fe(H2O)6](NO3)3} is built up from [Fe(H2O)6]2+ octahedra and nitrate anions connected via hydrogen bonds. In iron(III) trinitrate pentahydrate {pentaaquanitratoiron(III) dinitrate, [Fe(NO3)(H2O)5 nitrate with pentagonal–bipyramidal coordination geometry, where two bidentate nitrate anions and one water molecule form a pentagonal plane.