SUCCESSIVE H2O BINDING-ENERGIES FOR FE(H2O)(N)(+)

The successive H2O binding energies, computed using density functional theory (DFT), are in good agreement with experiment. The bonding is e lectrostatic (charge-dipole) in origin for ah systems. The structures are therefore determined mostly by metal-ligand and ligand-ligand repu lsion. The computed structure for FeH2O+ is C-2 upsilon, where sp hybr idization is important in reducing the Fe-H2O repulsion. Fe(H2O)(2)(+) has D-2d symmetry where sd(sigma) hybridization is the primary factor leading to the Linear O-Fe-O geometry. The bonding in Fe(H2O)(3)(+) a nd Fe(H2O)(4)(+) is very complex because ligand-ligand and metal-ligan d repulsion, both for the in-plane and out-of-plane water lone-pair or bitals, are important.