Coffee With

Dedicated to theory: Prof Rudolph Marcus, Visiting Professor and Nanyang Professor at SPMS’ Division of Physics & Applied Physics.

On a late July afternoon at NTU’s School of Physical & Mathematical Sciences (SPMS), the usual quiet of the hallways has been replaced by the chatter of excited voices. It’s the first day of Convocation 2009, and SPMS’ pioneering cohort (all in their graduation gowns) have returned to meet their professors, with animated updates on their new jobs.

Their voices carry into the office of Prof Rudolph Marcus. A Nobel laureate in Chemistry (1992) with a distinguished list of academic and research honours to his name, he is a leader in theoretical chemistry. But at this moment, Prof Marcus is hard at work emailing his postdoctoral and graduate students at the California Institute of Technology (Caltech).

“There!” he says, carefully putting aside his MacBook before turning to us with a smile. “What can I do for you?”

AN EARLY LOVE FOR MATH AND SCIENCE
Prof Marcus was born in Montreal, Canada, in 1923, and his interest in the sciences began with mathematics and chemistry during his time in high school. He spent his undergraduate and graduate years at McGill University studying chemistry, with a leavening of math courses, and upon receiving his PhD in 1946, Prof Marcus went to Ottawa to join the postdoctoral programme at Canada’s National Research Council (NRC).

In 1948, he formed a partnership with a fellow student at NRC to study theoretical papers related to their experiments. It was here that he first discovered a love of theoretical enquiries. “There were no theoretical chemists in Canada at the time,” he recalls, “and as students, I don’t think we ever considered how or where theories were conceived.”

EXPERIMENTATION AND THEORY
That same year, Prof Marcus received an offer to pursue his newfound interest at the University of North Carolina, and in February of 1949, he headed south to warmer climes and a fresh adventure in learning. A three-month immersion in the basics of theoretical work proved a marvellous experience, and he soon turned to studying particular problems in chemistry.

In 1951, Prof Marcus accepted a faculty position at the Polytechnic Institute of Brooklyn. Though he continued to conduct experiments while pursuing his theoretical investigations, it soon became clear that it was in the latter that he found the greatest fulfilment. By 1960, Prof Marcus had decided to bring the experimental part of his research programme to a close – there was too much for him to explore in the theoretical aspects, especially in the field of electron transfers.

Despite his passion for theoretical research, Prof Marcus believes that his experimental background has nevertheless coloured his particular approach to it. “I drew upon experimental findings or puzzles for theoretical problems to study,” he explains. “This interaction of experiment and theory, each stimulating the other, has been – and continues to be – one of the joys of my experience.”

In 1964, Prof Marcus joined the faculty of the University of Illinois in Urbana-Champaign, and since 1978, has been with Caltech as the Arthur Amos Noyes Professor of Chemistry. Encouraged by the investigations of his colleagues in the fields of unimolecular reactions, intramolecular dynamics and electron transfer processes, as well as by the rapidly growing experimental work in these areas worldwide, he turned to these topics with renewed vigour.

Colleagues: NTU President Dr Su Guaning with Prof Marcus at a dinner hosted by SPMS on 21 July, in celebration of the opening of the new SPMS building.

NOBEL HONOURS
Prof Marcus’ theoretical enquiries are built on the careful examination of existing concepts. “It’s about looking at all the experimental data, trying to think through it, and then coming up with some kind of theory that can explain it,” he says. “If you want to have developments across a whole area, and to try and solve a particular problem like solar energy conversion, then there is a real advantage to having people with different expertise, and bringing them together – but if you want truly original ideas on a particular topic, then maybe a single investigator is best.”

For Prof Marcus, the work of theoretical chemistry is a simple matter of coming to grips with the problem before him. “Almost everything that I am studying is some sort of puzzle,” he explains. “The results may seem well-defined enough for an answer, but whether they have the simplicity that I search for in an answer, is a key question.”

In 1992, Prof Marcus was recognised by the Nobel Committee for his theoretical research on electron transfers, and for a range of contributions that have greatly stimulated experimental developments in chemistry. The processes that he studied – the transfer of electrons between molecules in solution – underlie a number of critical chemical phenomena, and the practical consequences of his theories extend over many areas in the field.

THE NTU CONNECTION
The voices down the hall have subsided somewhat, with only the occasional laugh to break the quiet. In recent years, Prof Marcus has made a number of visits to NTU as a speaker at the Institute of Advanced Studies and SPMS. This year, he accepted a position as Visiting Professor and Nanyang Professor at SPMS’ Division of Physics & Applied Physics, and was among the luminaries who spoke at the inaugural SPMS conference.

The sojourn has been instructive for Prof Marcus. “Normally at Caltech, I will be talking to my students and postdocs, and now we communicate mostly by email,” he says. “Singapore is a very different place from southern California, with a richness and diversity of people. Everybody knows how well Singaporean students do, how highly they rate, and it’s been interesting for me to learn more about that. My many stimulating discussions here include those with colleagues down the hall, and particularly the ones with SPMS’ Head of Physics & Applied Physics, Prof Alfred Huan. And when it comes to science policies, I enjoy very much exchanging ideas with your Provost, Prof Bertil Andersson.”

Having taught and conducted research at premier institutions in North America and Europe, as well as travelled widely as an authority in the field, Prof Marcus has a unique insight into the continuing internationalisation of research. “The more the different countries are made equal by having their educational levels lifted up, the better for society as a whole,” he says. “It’s good when research grows and becomes more universal across the globe.”

THE WILL FOR CHANGE


	“Everybody knows how well Singaporean students do, how highly they rate, and it’s been interesting for me to learn more about that.”

It seems safe to say that this is a signal moment for the worlds of science and technology, with an unprecedented amount of public interest in how they can tackle the issues of energy and climate change. Prof Marcus’ theoretical research has had an impact on these problems; in the field of solar energy conversion, one particular effect that he discovered was cited by the Nobel committee. Another theory that he derived for rates of certain types of reactions of the gas phase has also been used in various elementary reactions related to combustion.

For Prof Marcus, the solutions that science can provide are tempered by an awareness of their limits in the public sphere. “I am confident that science can give answers, but I don’t have confidence that these will be enacted, and become law,” he explains. “In other words, I imagine that our current difficulties, as complicated as they are, can be analysed enough – maybe even have been analysed enough – to provide some rough predictions. But whether society will then make the changes that will permit improvements in the climate situation – that only time can tell.”

Prof Marcus remains deeply committed to the more immediate challenge of solving the problems before him. “A recurring theme is that when you look at new experiments and articles, you see that there really are many puzzles that are yet to be explained,” he says. “When I see that, it takes me right back to the days when I was a student in my math class, trying to solve a problem...”