He was an Emeritus Professor of Physical Chemistry at the University of Cambridge and a Life Fellow of Emmanuel College.
[1][2] Thrush studied the atom and free radical reactions in the gas phase of spectroscopic methods.
He made the first comprehensive examination of the absorption spectra of free radicals in homogeneous explosions using flash photolysis.
He was interested in chemiluminescence and produced a series of papers on the formation of electronically excited molecules in transfer or recombination reactions.
He also studied the rotational spectra of free radicals (NH2, PH2, PH) using the Zeeman effect to bring them into resonance with a far infrared laser.