A DFT study of the hydration of monophosphate complexes of iron (III), Fe3+(H2PO4-)(H2O)5

A systematic theoretical DFT study of the bonding between the cation Fe3+ and the anion H2PO4- was carried out. The role of water ligands is presented. Several isomers with tetrahedral, bipyramidal and octahedral environments around the iron ion were investigated. 5-fold coordination of the Fe3+ cation is found when 5 and 6 water molecules are included. Calculated infrared spectra are also presented.