“This award, I think,
is an award to Penn,
and it’s an award to interdisciplinary science throughout the world,”
Dr. Alan G. MacDiarmid, the Blanchard Professor of Chemistry, was saying.
“It is also an award to the teaching of young persons and to the
teaching of older persons. Because all of us here are students.”
MacDiarmid made his characteristically
generous remarks to a group of administrators and faculty who had gathered
in Houston Hall last month to honor him for winning the Nobel Prize in
Chemistry, an award he shared with former Penn physics professor Dr. Alan
J. Heeger (now at the University of California-Santa Barbara) and Dr.
Hideki Shirakawa of the University of Tsukuba, Japan. The Royal Swedish
Academy of Sciences awarded the prize to the three for the discovery and
development of conductive polymers.
“Most
of us recognize plastics to be insulators—things that are wrapped
around the wires to keep electricity from being lost —but Alan and
his colleagues made the revolutionary discovery that plastics can, after
certain modifications, be made electrically conductive,” said Dr.
Robert Barchi Gr’72 M’72 GM’73, the provost. “This
discovery created a research field of great importance to both chemists
and physicists,” he added, one that “unleashed a flood of interdisciplinary
studies that continue to grow today.” It has also led to such wide-ranging
applications as shields for computer screens, rechargeable batteries and
flexible plastic transistors and electrodes, to name just a few.
The
award comes a year after another member of the Penn community—Dr. Ahmed
Zewail Gr’74 Hon’97—garnered the 1999 Nobel Prize in Chemistry, and three
years after Dr. Stanley B. Prusiner C’64 M’68 Hon’98 won the 1997 Nobel
Prize in Physiology or Medicine. But it is the first time that a member
of the Penn faculty has won a Nobel Prize since 1980, when Dr. Lawrence
R. Klein, the Benjamin Franklin Professor Emeritus of Economics, won in
economics. The 73-year-old MacDiarmid has been a member of the Penn faculty
since 1955, having studied at the University of New Zealand, the University
of Cambridge and the University of Wisconsin. He has won numerous other
awards.
Penn’s
president, Dr. Judith Rodin CW’66, said that the prize is a “validation
of the extraordinary faculty that we have,” and that MacDiarmid’s work
“is at the pinnacle of the interdisciplinary nature of our aspirations.”
The
interdisciplinary collaboration between MacDiarmid and Heeger, a physicist
who served as director of Penn’s Laboratory for Research on the Structure
of Matter [LRSM], was indeed vital to the discovery.
“This
experiment in interdisciplinary research at LRSM has been a real model
for the rest of the world,” agreed MacDiarmid. “As Alan Heeger
and I found, you have to learn a different language, a different lingo,
for a physicist to talk to a chemist and a chemist to a physicist.”
MacDiarmid,
Heeger and Shirakawa showed that polymers can conduct electricity if they
are “doped” by removing or introducing electrons, and if they consist
alternately of single and double bonds between carbon atoms. According
to his homepage, MacDiarmid began research in 1973 on (SN)x, “an unusual
polymeric material with metallic conductivity,” but his interest in organic
conducting polymers “began in 1975 when he was introduced to a new form
of polyacetylene” by Shirakawa.
MacDiarmid
recalled that he invited Shirakawa to Penn to study polymers after they
met over a cup of green tea at a conference at the Tokyo Institute of
Technology, where MacDiarmid was giving a lecture. When MacDiarmid—who
noted that he likes “pretty things”—showed Shirakawa a “golden-colored”
polymer made of silver nitride, Shirakawa showed him a “beautiful silvery
polymer” made of polyacetylene.
“I said, ‘If I can get some money, could you come and join me
for a year at Penn?’” MacDiarmid said. “And he said ‘Yes.’”
While
at Penn, they soon found that Shirakawa’s silvery polymer “showed some
conductivity, not very high, but this elemental analysis also showed that
there was impurity in it. So we said, ‘Well, obviously, you make it more
pure, you get a higher conductivity.’” But, MacDiarmid noted, Shirakawa
found that “the purer he got it, the more the conductivity decreased
instead of increasing.” They then added iodine, which removed some
of the tightly packed electrons, “and suddenly the conductivity increased
within a few seconds to millions and billions of times higher than what
it was before.”
MacDiarmid
and Heeger enjoyed a “very, very crucial and successful collaboration
for about 10 years,” MacDiarmid recalled. “We would arrange to get together
every Saturday morning—we strictly said not to discuss anything
specific; purely to sit down and let our minds wander and consider crazy
things, which we did.”
From
his point of view, MacDiarmid said, the “whole climate of Penn is really
just great” for research, and its interdisciplinary strengths are complemented
by the quality of its students.
“We
all know that the research done in a given research group cannot be better
than the students—undergraduate, graduate or post-doctoral,”
he said. “If you have very good people working—not for you but
with you, then the chances of finding very important, critical, unexpected
things are pretty high.”
