Written by Professor Peter Daivis

(This is an extended version of Peter's obituary written for the Age newspaper.)

Ian Snook was a Professor of Physics at RMIT University and long-term Visiting Scientist at CSIRO who excelled as a researcher, mentor and lecturer. He was internationally recognized for his influential work in computational physics, typically characterised by its innovation and illuminating physical insight.

Ian was born on June 13, 1945 in Cremorne, NSW where his father was stationed during the second world war. When he was only one year old, his father died after appendix surgery, and his mother Joan raised him and his sister Frances with the support of Legacy. Ian, a Quaker, received his secondary education (1958 – 1963) at the Friends School, Hobart, which was co-founded by his great grandfather. At the Friends School, he was Dux of the school and won prizes for Mathematics, Chemistry and Geography. Here he discovered his aptitude for pattern recognition, which he later considered to be the key to his scientific ability and also to many of his other interests including music and art.

Ian excelled in his undergraduate degree in chemistry at the University of Tasmania, completing an honours project on polyhalides with Dr G.H. Cheeseman and embarking on his PhD studies under the supervision of Dr Tom Spurling with the support of a postgraduate scholarship from General Motors Holden. During his PhD, he attended his first international conference in Sydney where he met John Barker, whose pioneering research in the field was an inspiration to Ian and many others. After John’s death, Ian wrote an article for a commemorative issue of Molecular Physics about John Barker’s influence on Australian science. Ian often returned to the subject of intermolecular potentials, making significant contributions at intervals throughout his career.

He met Marie, his wife of 43 years, while employed as a demonstrator in the chemistry labs at the University of Tasmania and they were married in 1970. They moved to Melbourne, where Ian completed his PhD with Tom Spurling at CSIRO at Fisherman’s Bend.

His first paper was published in 1970, and his early research concerned studies of intermolecular potentials using experimental data and theoretical computations.

From CSIRO, he went to work with David Craig at the Research School of Chemistry at the Australian National University in Canberra (1971 – 1973). His ANU contemporaries from this period include many of the leading figures of Australian Theoretical Chemistry. At CSIRO and then ANU he began a long friendship and productive collaboration with Bob Watts. While at ANU, he also met Bill Hoover, visiting from the USA and Denis Evans then a PhD student of Bob Watts), who both became long-time friends.

Ian and Marie’s first son Stuart was born in Canberra in December 1972 on the day before Ian’s interview for an academic position in the Department of Applied Physics at RMIT, Melbourne. He started his appointment there in May 1973, about a year after Bill van Megen, who he had also met at ANU. Ian and Bill were instrumental in the modernization and renewal of physics at RMIT initiated by the then Head of Department, Robert Budwine. With teaching loads at the time of 16 to 19 contact hours per week and a still-developing research culture, this was a very tough environment in which to establish a research career, but Ian and Bill combined their talents and managed to do world-leading research in colloid physics.

Ian Snook and Bill van Megen were the first researchers at RMIT to receive funding from the then-named Australian Research Grants Council in the mid-1970’s. Following that, he was successful in gaining 12 more ARC grants. Snook and van Megen supervised a group of Masters degree students who were amongst the first higher-degree graduates at RMIT. Soon afterwards, Ian was instrumental in the development of PhD awards at RMIT, and he supervised Tony Hughes (now at CSIRO) who became one of the earliest PhD graduates of the university.

 Ian and Marie’s second son, Graeme, an electrochemist at CSIRO, was born in 1975 in Melbourne. In 1976 – 1977, Ian visited the IBM Research Laboratory in San Jose, California, where he interacted with John Barker, Douglas Henderson and Farid Abraham, and did seminal computations of the nanoscale oscillations in the molecular density of a fluid next to a hard wall. This visit to the USA also coincided with the birth of Ian and Marie’s third child and only daughter, Tamara.

In the years that followed, Ian established a strong research career and became an internationally recognized researcher, authoring or co-authoring more than 200 peer-reviewed papers.

Ian became a highly appreciated invited speaker at many international conferences. This wasn’t only because of the excellent science he presented. He had a unique style of presentation that often involved very funny diversions and asides, illustrated with sometimes unflattering photos of his collaborators. His presentations would veer off into stand-up comedy and back to serious science in a couple of sentences, and this ensured that he never lost the attention of the audience.

As a result of his warm personality and excellent scientific reputation, Ian had many international collaborators from all over the world, including the USA, Ireland, Europe and Japan. In recent years he often visited Mainz, Germany where he had a long-term position as a visiting scientist with Kurt Binder’s group at the Johannes Gutenberg University.

Ian’s scientific contributions ranged very widely, from X-ray scattering studies of the porosity of brown coal to the origins of van der Waals forces between atoms. He worked on the Langevin equation and Brownian motion, publishing a book on this subject in 2007. In collaboration with his great friend, the mathematician Ed Smith, he worked on the complex and difficult subject of hydrodynamic interactions in colloidal suspensions. His most highly cited work was on the density oscillations in fluids near a hard wall. He has worked on the nucleation and growth of nanoparticles, surface physics and recently on new structures of carbon including graphene. To all of these subjects he brought his characteristic enthusiasm, wisdom and physical insight.

As a lecturer, supervisor and mentor, Ian excelled. He was an inspiring lecturer of first year physics for many years, contributing to strong postgraduate recruitment. Ian was the chief or associate supervisor of 29 postgraduate students, with many of them going on to appointments at prestigious institutions such as Cambridge and Oxford Universities, Imperial College, Argonne National Laboratory, ANU, CSIRO and DSTO. His desire to achieve the best outcome for each and every student meant that he was often called upon to take over the role of replacement lecturer or supervisor when things went wrong.

Ian was a very genuine, unassuming and extremely modest man, despite his considerable achievements. He always put the needs of his family, students, colleagues and friends ahead of his own. Many of his students became lifelong friends. He had a gift of nurturing and encouraging students to achieve their potential. Ian often marvelled at how lucky he was to have had such excellent students. It was true, but lots of dedication and hard work on his part also played a part.

Tragically, Ian and Marie’s son Stuart died in October 2004. This event had a profound effect on Ian, both emotionally and physically.

Ian died on the 7^th of April, 2013, after an 18 month struggle with bowel cancer. (During this time, he was continually under treatment - chemotherapy, radiotherapy or surgery.) He continued doing his research, and pursuing his other interests with a passion so typical of his life right up until his death.

He is survived by his wife Marie, son Graeme and daughter Tamara, and two grandchildren.

After his death there was an enormous response to a request for comments in memory of Ian. Many of them came from students he had supervised. He was universally loved, respected and admired, and he will be remembered as one of those rare individuals who was able to create an enormous sphere of positive influence on many people.