John Simons has made many original contributions in photochemistry and photophysics, molecular reaction dynamics, and biomolecular spectroscopy. His principal achievements include incorporating an ultra-high-speed rotor into a crossed supersonic molecular beam system to provide a unique method for studying photochemical reaction dynamics.

He pioneered Doppler-resolved, polarised laser spectroscopy, providing a three-dimensional view of reactive molecular collisions — their stereodynamics. He also combined ultraviolet and infrared laser spectroscopy and quantum chemical computation to reveal the conformational structures and interactions of small biomolecules, especially carbohydrates and peptides, free from extraneous environmental ‘disturbance’.

John’s principal awards include the Tilden, Polanyi, Spiers and Liversidge Lectureships and the Chemical Dynamics Award of the Royal Society of Chemistry (RSC). He received the Humphry Davy Lectureship and the Davy Medal of the Royal Society, and the George C. Pimentel Memorial Lectureship and a visiting Miller Fellowship from the University of California, Berkeley. He served on the Councils of the Royal Society and the Faraday Division of the RSC, acting as the latter’s Honorary Secretary throughout the 1980s and, subsequently, as its President.