The isomerism, optimized molecular structure, UV spectrum, metal-ligand bond strength, and vibrational assignment of tris(triflouroacetylacetonato)iron(III), Fe(TFAA)3, were investigated by the aid of theoretical calculations (using DFT and Atoms-in-Molecules (AIM) at the B3LYP/6-311++G(d,p) level) and experimental methods (vibrational and UV spectroscopy). To explore the effect of the CF3 substituent in the β-position on the properties of complex, the above theoretical and experimental results of the titled complex compared with the corresponding data for tris(acetylacetonato) iron(III), Fe(AA)3. Both theoretical and experimental results confirmed that there is no significant difference in the strength of the Fe−O bond in these complexes. The effect of the CF3 group on the experimental vibrational bands of the chelated ring agrees with the calculated results. Comparing the observed and calculated vibrational spectra suggests that vibrational spectroscopy cannot be used to determine the type of isomer in the sample. However, due to the small difference of energy between the fac and mer isomers in the Fe(TFAA)3, the presence of both isomers in the sample is possible. The computed quantum chemical descriptors of Fe(TFAA)3 and Fe(AA)3 were also compared.

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