A DFT study of two diiron (II) synthetic model compounds and their diiron(III) peroxide oxygenation products

Abstract

Unrestricted density functional theory calculations have been conducted on two diiron(II) synthetic model compounds. Calculations employed the BPW91 and BOP density functionals with both high-spin and broken symmetry lowspin representations of weakly coupled high-spin irons. Comparison of the calculated and crystallographic structures is made, and good agreement is found with both spin representations. Raman spectral data are available for the diiron(III) product of the reaction with O2 to form a bridged peroxide. Calculated harmonic frequencies confirm the experimental assignments. Small geometry differences between the high spin and broken symmetry results are seen in bond lengths, angles, Raman frequencies, and spin densities associated with oxo and peroxo bridges in the diiron(III) oxidation products.2 to form a bridged peroxide. Calculated harmonic frequencies confirm the experimental assignments. Small geometry differences between the high spin and broken symmetry results are seen in bond lengths, angles, Raman frequencies, and spin densities associated with oxo and peroxo bridges in the diiron(III) oxidation products.