Â鶹´«Ã½

Professor Tony McCaffery

Tony McCaffery, Professor of Chemical Physics and stalwart of the Chemistry Department at the Â鶹´«Ã½ of Sussex for over 50 years, sadly passed away at the age of 89 on 13 May 2024.

Tony was born in Brentford in 1935. Following national service with the RAF, he returned to the UK to read for a Chemistry degree at Exeter Â鶹´«Ã½. Tony excelled in his undergraduate studies and went on to a PhD using circular dichroism spectroscopy to probe optical activity in transition metal complexes under the supervision of Stephen Mason. During his graduate studies, he was inspired by a talk given by Carl Ballhausen, on the essential role angular momentum plays in the description of the structure and dynamics of atoms and molecules. In 1964 Tony was awarded a prestigious CIBA-GEIGY Fellowship, which he chose to take at the Ballhausen laboratory in Copenhagen. Angular momentum theory, the interaction of polarised light with molecules, and the beautiful symbiotic interaction between theory and experiment, became defining themes of Tony’s research. Following a productive period working with Paul Schatz at Â鶹´«Ã½ of Virginia on Magnetic Circular Dichroism (MCD), Tony returned to the UK to take up a lectureship at the Â鶹´«Ã½ of Sussex in 1968.

At Sussex Tony and his graduate students built one of the UK’s first MCD systems which evolved into novel apparatus for investigating the degree of circularly polarised emission for molecules in high magnetic fields. Realisation of the utility of measuring rotationally resolved circularly polarised molecular fluorescence led to high precision studies of gas phase rotational energy transfer in laser excited molecules. With the acquisition of extremely narrow bandwidth tuneable lasers and using Doppler-free spectroscopic techniques Tony and his group were able to study the correlation between angular momentum and velocity changes leading to new insights into the mechanisms underpinning gas phase molecular energy transfer. In 1993 Tony was awarded the RSC Spectroscopy prize for ‘the development and application of polarization spectroscopy techniques to the study of atomic and molecular interactions, particularly in the gas phase’.

Tony was a pioneering all-rounder – a brilliant scientist and innovative educator who took on several academic leadership roles, while always making time to inspire and mentor his students, colleagues, and collaborators. He supervised over 30 PhD students and was an exceptional supporter of female scientists. At Sussex, he was a Pro-Vice-Chancellor (PVC) of the Â鶹´«Ã½ in the 1990s and early 2000s, and his open-mindedness led to many visionary innovations. He was a keen sportsman, playing cricket from a young age, stoolball after arriving at Sussex, and later tennis.

Tony continued to be an active researcher after his official retirement, producing a string of publications in which he explored the significance of angular momentum conservation in controlling the outcome of collisions and other dynamical processes. However, in December 2019, at the age of 84, he felt it was time to step back. We will fondly remember his quick-witted humour, formidable intellect, and competitive banter over a beer, but most of all his kindness, friendship, and modesty. He will be greatly missed. He is survived by his wife Juliet, five daughters and 10 grandchildren.

Authors: (Â鶹´«Ã½ of Sussex), Katharine Reid (Â鶹´«Ã½ of Nottingham) and Angus Bain (UCL)