density-functional theory: DFT) and
strove to evolve the all-important exchange-correlation functional
in DFT as far as possible.
Tremendously encouraging as well was the work of Tom Ziegler
(University of Calgary, Canada). He was the first to apply the new
exchange-correlation functionals to significant and challenging
problems in organometallic chemistry in the mid-1980s, demonstrating
the great promise of DFT as a practical and accurate computational
tool.
What would you rate as your most difficult or trying professional
moment?
For a while, my Ph.D. thesis seemed doomed never to see
completion! After writing the first-ever non-LCAO grid-based code
for molecular orbital calculations in chemistry, I computed X-alpha
spectroscopic properties of several diatomic molecules. The
resulting bond energies were seriously in error. No amount of
debugging effort could change those baffling numbers... until
discussions with Tom Ziegler (who was a postdoctoral fellow at
McMaster at the time) revealed that I was performing the atomic
reference calculations incorrectly. That is how I learned the
difference between density functionals and SPIN density functionals.
After all that, the thesis examination itself was suspended by
the external examiner for insufficient referencing and too few
computational results! Though a disappointing setback, the
criticisms were correct, and a much-improved document was submitted
several months later and successfully defended.
Other most trying professional moments? Lecturing to freshman
classes of hundreds of engineering students!
Which of your professional achievements brings you the most
satisfaction?
Twice, once for diatomics and a second time for polyatomics, I
have written programs from scratch to perform non-LCAO grid-based
computations of electronic orbitals in molecules. These have been
very satisfying and creative efforts for me, and I hope to return to
this kind of work again in the future.
Also, I am very pleased to have been lucky enough to discover a
path to honing the accuracy of density-functional theory to its
present level of respectability. We progressed significantly from
the vagaries of the old X-alpha method to the widespread popularity
of modern DFT in the last two decades of the twentieth century.
Did you expect to become highly cited, or is this surprising to you?
It was unexpected. My work was known only to a relatively small
community of theoretical and computational specialists, until DFT
methodologies were adopted by Peter Gill, Benny Johnson, John Pople,
and Michael Frisch into the GAUSSIAN molecular structure program in
1992. This was the event that made DFT available, for the first
time, to an enormous user base of computational chemists.
What lessons would you draw from your work to pass on to the next
generation of researchers?
Persistence. Persistence. Persistence. Ask the BIG questions...
the general questions... and don't be sidetracked until you are
perfectly satisfied with the answers (if that ever happens!).
If you had the power to make a single, sweeping change in the way that
scientific research is conducted and presented, what would it be?
Preserve and protect democratic funding of small scale,
independent researchers. True breakthroughs are the outcome of
serendipity and are (by definition) unforeseen. It is misguided to
place too much faith in the funding of strategic, highly networked,
business-like, results-driven research. The independent but
promising dreamer should not be forgotten.
Dr. Axel D. Becke
Queen’s University at Kingston
Department of Chemistry
Kingston, Ontario, Canada
cites
:
n
this interview, Dr. Axel Becke of Queen’s University at
Kingston, Ontario, Canada, discusses his highly cited work on
the density-functional theory of atomic and molecular
structure. Six of Dr. Becke’s papers on this topic have been
cited a total of 4,663 times. According to our analysis of
high-impact papers in chemistry, Dr. Becke’s most-cited
paper is "Density-functional thermochemistry .3. The role
of exact exchange," (Journal of Chemical Physics,
98 [7]:
5648-52, 1 April, 1993), which has been cited more than 3,208
times. Dr. Becke is also the recipient of the 2000
Schroedinger Medal from the World Association of Theoretically
Oriented Chemists.
of
the theoretical nuclear physics group, where I received a thorough
grounding in quantum mechanics and many-body theory. I found the
(many) books of John Slater on the quantum theory of matter to be
highly readable and especially useful and inspiring.
