Calculated oxidation potentials of Me 4 QH 2 in the presence of Al 3+ differ between 0.11-0.18 eV from the experimental E ox of -0.28 eV. The deviation from the experimental value is moderate but acceptable. However, we would like to remember that calculated oxidation potentials of Me 4 QH 2 without considering Al 3+ presence already exhibited a moderate deviation from the experimental value. In fact, regarding the shift of the oxidation potentials when aluminum is considered (∆E ∅→Al ox ) or upon methylation ∆E M et ox , the agreement with experimental figures is very reasonable. In this sense, our calculations replicate the experimental trend that Al 3+ disfavors Me 4 QH 2 oxidation (i.e., negative (∆E ∅→Al ox ) , and that methylation favors oxidation (positive values of ∆E M et ox ).