John Murrell

John Murrell made major contributions to chemistry in the fields of electronic spectroscopy, intermolecular forces, potential energy functions and valence theory. In electronic spectroscopy, methods were derived for determining quantitative substituent parameters from frequency shifts; inductive shifts of pi and sigma electrons could be of opposite sign, and this was later shown to be valuable for assigning photoelectron spectra. His research on strongly conjugating substituents and intramolecular charge transfer have yet to be superseded. In the field of intermolecular forces, John was the first to derive the so called MSMA exchange perturbation method, which is widely used for interactions in the Van der Waals region and is the basis of several semi-empirical potentials. He showed that the variation perturbation method is invaluable for calculating intermolecular parameters and for deriving damping factors for dispersion terms. A new general strategy for obtaining analytical potential functions for small polyatomic molecules, based on the many-body expansion was devised. These potentials have been used for studies of vibrational motion, photodissociation and bimolecular reactions by other leading workers.

Professor John Murrell FRS died on 25 January 2016.

Biographical Memoir