Hammett equation parameters optimised for improved predictive power
Update overcomes limitations and eliminates human biases intrinsic to the original formulation
A generalised version of the Hammett equation has been developed by researchers in Switzerland. Anatole von Lilienfeld and his team at the University of Basel used a statistical method to optimise two parameters that determine the Hammett equation, allowing the relationship between free energy and substituents to be determined with higher accuracy. The new version will allow users to predict activation energies in non-aromatic molecules with multiple substituents.