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I
was born in Akron, Ohio on June 6, 1943, one year to the day before D-Day,
the allied invasion at Normandy. The youngest of four children, I was
brought up in a wonderfully stable, loving family of strong Midwestern
values. When I was three my family moved to Kansas City, Missouri where
we lived in a beautiful large home in a lovely upper-middle class neighborhood.
I grew up there (at least to the extent one can be considered to be grown
up on leaving for college at age 18) and was convinced that Kansas City,
Missouri was the exact center of the known universe.
My mother, Esther Virginia Rhoads, was the third of six children of Charlotte
Kraft and Errett Stanley Rhoads, a wealthy manufacturer of furniture in
the Kansas City area. She liked the unusual name Errett so much that she
gave it to me as my middle name. She picked the name Richard after the
crusading English king (the Lion-Hearted), but being a good American and
suitably suspicious of royalty, she was fond of calling me "Mr. President"
instead. She had big plans for me, and loved me beyond all reason.
My father, Frank Dudley Smalley, Jr., was the second of four children
born to Mary Rice Burkholder and Frank Dudley Smalley (Sr.), a railroad
mail clerk in Kansas City. Although my father went by the name of June
(short for Junior), he never quite forgave his father for not having given
him a name of his own, and for not having aspired to more in life. My
father started work as a carpenter, and then as a printer's devil, working
for the local newspaper, The Kansas City Star, and later for a
farm implement trade journal, Implement and Tractor. By the time
he retired in 1963 he had long since risen to be CEO of this company,
and a group of several others that published trade journals in the booming
agriculture industry throughout the Western Hemisphere. He was incredibly
industrious, talented, and fascinated with both business and technology.
He had a wonderfully analytic mind, and loved argument, open discussion,
and homespun philosophy. During the depression in the early 1930's he
married my mother (who fell in love with his blue eyes) and was promptly
laid off from work. The story of his career is one of total dedication
to both his work and his family, a dedication that held steady through
a series of tribulatons, many of which I am only now beginning to appreciate.
He loved me too, but he could see himself in me, and knew my failings
through and through. Until late in life I was never quite good enough
for my father, and I suppose that is part of what drives me even now,
well after his death in 1992.
My interest in Science had many roots. Some came from my motner as she
finished her B.A. Degree studies in college while I was in my early teens.
She fell in love with science, particularly as a result of classes on
the Foundations of Physical Science taught by a magnificent mathematics
professor at the University of Kansas City, Dr. Norman N. Royall, Jr.
I was infected by this professor second hand, through hundreds of hours
of conversations at my mother's knees. It was from my mother that I first
learned of Archimedes,
Leonardo da Vinci,
Galileo,
Kepler,
Newton, and
Darwin. We spent hours together collecting single-celled organisms from
a local pond and watching them with a microscope she had received as a
gift from my father. Mostly we talked and read together. From her I learned
the wonder of ideas and the beauty of Nature (and music, painting, sculpture,
and architecture). From my father I learned to build things, to take them
apart, and to fix mechanical and electrical equipment in general. I spent
vast hours in a woodworking shop he maintained in the basement of our
house, building gadgets, working both with my father and alone, often
late into the night. My mother taught me mechanical drawing so that I
could be more systematic in my design work, and I continued in drafting
classes throughout my 4 years in high school. This play with building,
fixing, and designing was my favorite activity throughout my childhood,
and was a wonderful preparation for my later career as an experimentalist
working on the frontiers of chemistry and physics.
The principal impetus for my entering a career in science, however, was
the successful launching of Sputnik in 1957, and the then current belief
that science and technology was going to be where the action was in the
coming decades. While I had been a rather erratic student for many years,
I suddenly became very serious with my education at the beginning of my
junior year in the fall of 1959. I set up a private study in the partly
furnished, unheated attic of our home, and began to spend long hours in
solitude studying and reading (and smoking cigarettes). This happened
to be the year when I began to study chemistry for the first time. Luckily,
these years were some of the best ever for the public school system in
Kansas City, and my local high school, Southwest High, was one of the
most effective anywhere in the US as measured by scores on standard achievement
tests, and the fraction of students going on to college. My teacher, Victor
E. Gustafson, was a great inspiration. He had just begun to teach the
preceding year, and was full of love for his subject and for teaching,
and had an as yet unblunted ambition to reach even the slowest of students.
In addition, this was the first class I had ever taken with my sister,
Linda, who was a year older than I, and was a far better student than
I had ever been. The result was that by the end of the year, my sister
and I finished with the top two grades in the class. We hardly ever missed
a question on an exam. It was an exhilarating experience for me, and still
ranks as the single most important turning point in my life, even from
my current perspective of nearly four decades later. It was the proof
of an existence theorem. After my junior year, I knew I could be successful
at science. The next year I did equally well in physics with a wonderful
professor, J.C. Edwards, but my soul had already been imprinted by my
exposure to chemistry the year before.
My mother's youngest sibling, Dr. Sara Jane Rhoads, was one of the first
women in the United States to ever reach the rank of full Professor of
Chemistry. After earning her Ph.D. in 1949 with William von Eggers Doering,
who was then at Columbia University, she devoted her life to teaching
and research in the Department of Chemistry of the University of Wyoming.
She received the Garvan Medal of the American Chemical Society in 1982
for her contributions to physical organic chemistry, particularly in the
study of the Cope and Claisen rearrangements. She was the only scientist
in our extended family and was one of the brightest and, in general, one
of the most impressive human beings I have ever met. She was my hero.
I used to call her, lovingly, "The Colossus of Rhoads". Her
example was a major factor that led me to go into chemistry, rather than
physics or engineering. One of the most enjoyable memories of my early
life was the summer (1961) I spent working in her organic chemistry laboratory
at the University of Wyoming. It was at her suggestion that I decided
to attend Hope College that fall in Holland, Michigan. Hope had then (and
still has now) one of the finest undergraduate programs in chemistry in
the United States.
At Hope College I spent two years in fruitful study, but decided to transfer
to the University of Michigan in Ann Arborafter my favorite professor,
Dr. J. Harvey Kleinheksel, died of a heart attack, and the organic chemistry
professor with whom I had hoped to do research, Dr. Gerrit Van Zyl, announced
his retirement. While the next two years in Ann Arbor were successful,
I had become so entangled in a stormy love affair with a lovely girl back
at Hope College, that I was not able to concentrate as much on science
as I should have. I did, however, learn a lot. Most of all I learned from
my fellow students, and particularly from John Seely Brown, a graduate
student in mathematics who lived in an apartment down the hall in a small
house off campus (he is currently Director of Xerox's Palo Alto Research
Center, PARC). John displayed an audacity of thought and intellectual
ambition that I have rarely seen in any individual. My fellow housemates
and I were infected with the notion that we could master any subject,
and at times we did manage to at least feel that we got close.
By the time of my graduation in 1965, the job market for scientists in
the United States was at an all-time high, and even chemistry graduates
with just a BS degree were in great demand. Rather than proceeding directly
to graduate school, I decided to take a job in the chemical industry in
order to buy a bit of time to see what I really wanted to do in science,
and to live a little in the "real" world. It turned out to be
a terrific decision.
In the fall of 1965 I began work full time in Woodbury, New Jersey at
a large polypropylene manufacturing plant owned by the Shell Chemical
Company. I began as a chemist working in the quality control laboratory
for the plant, a 24 hour a day operation that in the mid 60's was quite
a wonderland of high technology. My first boss was a chemist named Donald
S. Brath. He taught his young professionals that "chemists can do
anything", and the time I worked under him was a wonderfully broadening
experience. I was teamed up with chemical engineers at the plant to study
problems with the quality of the polymer product. The Ziegler-Natta catalyst
system then in use by Shell to produce isotactic polypropylene was no
where near as efficient as those currently in use, and the level of inorganics
remaining in the polymer was high. Much of what we were concerned with
in those days revolved around this problem of high "ash" content
and how it affected the downstream applications. These were fascinating
days, involving huge volumes of material, serious real-world problems,
with large financial consequences. I loved it.
After two years I moved up to the Plastics Technical Center at the same
site in Woodbury, and devoted myself to developing analytical methods
for various aspects of polyolefins, and of the materials involved in their
manufacture, modification, and processing. Although I found my work at
Shell highly enjoyable, I realized it was time to get on to graduate school,
so I began to study seriously and to send out applications. At the time
I was most interested in quantum chemistry, and received several offers
for graduate assistantships in excellent schools. I was close to accepting
an offer from the Theoretical Chemistry Institute at the University of
Wisconsin when the automatic graduate student deferments from the Draft
into the US military were eliminated. This was in early 1968, during a
major buildup phase in the Vietnam War, and I decided it would be more
prudent to remain at Shell for a while since my industrial deferment was
still in effect.
In my off hours over the past few years I had met Judith Grace Sampieri,
who was a wonderful young secretary at Shell. We were married on May 4
ot 1968. Soon thereafter, even the industrial deferment was lost, and
we decided that I might as well reapply for graduate school. Since Judy's
family lived in New Jersey, I decided to apply to Princeton University,
and was accepted. In the late fall of 1968 I was reclassified 1A for the
draft and reported to the processing center in Newark for my physical.
At the end of the day I ended up in the group who had passed. We were
told to put our affairs in order since we would soon be called up. However,
in a great stroke of luck, within a week, my wife told me she was pregnant,
and within just a few more weeks my draft board reclassified me to some
status I do not remember, save that it meant I would not be drafted. On
June 9, 1969 Judy and I were blessed with the birth of a beautiful child,
Chad Richard. Later that summer, I held him in my lap as Neil Armstrong
first stepped out onto the Moon.
In the fall of 1969 I moved my new family up to Princeton to begin studies
and research for the Ph.D. in the Department of Chemistry. I was lucky
enough to be in the first group of graduate students to work with Elliot
R. Bernstein who was just starting as an Assistant Professor at Princeton,
after having spent a few years postdoctoral work at the University of
Chicago with Clyde A. Hutchison III, following doctoral training with
G. Wilse Robinson at CalTech. Elliot's research at the time involved detailed
optical and microwave spectral probes of pure and mixed molecular single
crystals cooled in liquid helium. I knew nothing about it at the time
I joined the group. I was certain that it was going to be both experimentally
and theoretically complex and challenging, but it seemed likely to be
worth the effort. My research project was the detailed study of 1,3,5-triazine,
a heterocyclic benzene analog that we expected would provide a poignant
testing ground for theories of the Jahn Teller effect. In the end we found
that the crystal field surrounding each molecule was insufficiently symmetrical
to provide the tests we originally sought, but much was learned. Most
importantly from my standpoint, I learned from Elliot Bernstein a penetrating,
intense style of research that I had never known before, and I learned
a great deal about the chemical physics of condensed phase and molecular
systems.
In the summer of 1973 we moved to the south side of Chicago so I could
begin a postdoctoral period with Donald H. Levy at the University of Chicago.
Levy had studied gas-phase magnetic resonance with Alan Carrington, and
had been doing some of the most impressive research anywhere in the world
with microwave/optical double resonance and the Hanle effect on NO2
and other open-shell small molecules. These were the earliest days when
tunable dye lasers were beginning to transform molecular spectroscopy,
and Levy's group was in the lead. The optical spectrum of NO2
was the most troublesome problem for molecular spectroscopists. Even though
it had only three atoms, the visible spectrum had far more structure than
anyone could understand. But since NO2 was readily available
and it displayed an extensive absorption spectrum just where the new lasers
could readily operate (500-640 nm), it was a favorite object for study.
Don Levy and one of his students, Richard Solarz, had made some major
advances with NO2 earlier that summer, so after I arrived in
Chicago I began to consider what I could do next. My biggest problem was
that my training at Princeton had been in condensed matter spectroscopy,
and the ultrahigh resolution gas-phase spectral techniques being used
by the Levy group were going to take months to understand. The detailed
physics of rotating polyatomic molecules with spin is extremely complex.
I was familiar only with the physics of molecules frozen still in a crystal
lattice near absolute zero.
When we first arrived in Chicago, Don Levy was in Germany for a several
month-long visit, so I had an opportunity to do some extended reading
and to prepare for the final oral exam for the Ph.D. degree back in Princeton.
At that time in the Chemistry Department at Princeton, the final oral
exam consisted of a defense of three original research proposals. I spent
many hours in the Univ. Chicago chemistry department library reading recent
journal articles, searching for possible topics for these research proposals.
On one day I read a new paper by Yuan Lee and Stuart Rice on the crossed
beam reaction of fluorine with benzene (J. Chem. Phys. 59,
1427 (1973)] in one of Yuan's "universal" molecular beam apparatuses.
It was the sort of experiment that was to lead to Yuan Lee sharing the
Nobel Prize in 1986 with John Polanyi and Dudley Herschbach. I was deeply
struck by a passage in the paper which said that the supersonic expansion
used to make the benzene molecular beam was strong enough to cool out
essentially all rotational degrees of freedom. That was just what I needed.
Since I didn't understand rotating molecules yet, perhaps I could just
stop them from rotating in the first place!
As a result of this exciting day in the Chicago library, one of the proposals
I presented to the Princeton Ph.D. committee later that fall was to use
a supersonic expansion to cool NO2 to the point that only a
single rotational state was populated, and then to use a tunable dye laser
to study the now greatly simplified spectrum. I had found in further reading
that the current supersonic expansion techniques actually would not get
cold enough, so I added the further use of an electric resonance "state-selector"
to do a final sorting out of just a single rotational state for study.
I recommended, in fact, that the 10 meter state-selector beam machine
of Lennard Wharton at Chicago could be used.
When Levy returned from Germany, I told him of this proposal, and we discussed
it in some depth. He was intrigued, but was concerned that too much of
the NO2 would dimerize to N204 before
sufficient cooling was obtained. A few weeks later we discussed it again,
and became sufficiently excited to walk down the hall and ask Lennard
Wharton what he thought. Len lit up like a light bulb.
Wharton argued that we should first do the experiment on NO2
expanded in a supersonic free jet, and leave the much more elaborate state-selected
experiment for later. I told him that wouldn't be cold enough - the lowest
rotational temperature reported for a polyatomic molecule in a supersonic
beam that I was aware of at that time was 30 K still way too hot to achieve
the simplification we needed. Wharton smiled wryly and swiveled in his
chair to reach a research notebook from the shelf behind him. After reading
a few pages he looked up and asked "would 3 K be cool enough?".
He had already built a liquid hydrogen cryopumped supersonic beam source
with argon, and in the research notebook had measured data for the velocity
distribution showing the translational temperature was cooled to 3 K.
That, I knew from my Ph.D. proposal, would be quite cool enough in the
case of NO2 to collapse the rotational population to just a
few levels. We would simply mix in a percent or so of NO2 into
the argon and make a "seeded" supersonic beam. This would avoid
the N204 formation that concerned Don Levy, and
may just possibly cool the rotational degrees of freedom to near the translational
temperature of the argon carrier gas. Thus began the collaboration that
led to supersonic beam laser spectroscopy.
On the night of August 8, 1974 (the night Nixon resigned from the US Presidency)
we recorded the first jet cooled spectrum of NO2. The next
morning Don Levy saw the spectrum for the first time, and immediately
recognized its significance. Molecular physics had changed. Now we could
study at least small polyatomic molecules with at the same penetrating
level of detail previously attained only for atoms and diatomics.
A year later, Lennard Wharton came back from a trip to France where he
had visited with Roger Campargue and learned of the concept of the "zone
of silence" that exists in an expanding gas at sufficiently high
densities. While this zone is surrounded by shock waves where the gas
is heated to very high temperatures, within the zone the expanding gas
is exactly as cold and unperturbed as it would be if the gas expanded
into a perfect vacuum, forming no shock waves at all. Campargue had learned
to fabricate a ultrasharp edged "skimmer" that could penetrate
the "Mach disc" at end of the zone and transmit the gas streaming
along the center line of the zone of silence to form the most intense,
coldest supersonic beams ever produced. Wharton told Don Levy and me that
using helium in such an apparatus we could easily get cowl to 1 K and
perhaps even lower. I was stunned. I knew that 1 Kwas low enough to freeze
out the rotational motion of even medium-sized molecules such as benzene
and naphthalene, and all such molecules could now be studied without rotational
congestion.
Later that same day in a hallway conversation Len Wharton and I realized
we didn't need the skimmer. The probe laser beam could easily penetrate
the shock waves without perturbation, and we could image just the fluorescence
from the laser-excited ultracold molecules in the zone of silence. We
quickly built a new apparatus that incorporated these ideas. With the
spectroscopic insight of Don Levy and with a series of graduate students
we published the pioneering papers on not only jet cooled spectra of ordinary
molecules such as NO2, and tetrazine, but also on the first
van der Waals complexes with helium (e.g. HeI2), and with the
vital collaboration of Daniel Auerbach the first supersonic beam study
of a metal atom-rare gas complex, NaAr.
In the summer of 1976 my family and I moved to Houston, Texas where I
had accepted a position as assistant professor in the chemistry department
at Rice University. I knew of Rice principally because of the beautiful
laser spectroscopy that was being done there by Robert F. Curl, and I
wanted to collaborate with him much the same as I had with Don Levy. The
first supersonic beam apparatus I set up was a free jet machine similar
to that I had used in Chicago, but adapted to use pulsed dye lasers in
the ultraviolet so that we could study more ordinary molecules such as
benzene. My first proposal to the National Science Foundation was for
a much larger, more ambitious apparatus that would for the first time
use pulsed supersonic nozzles. With these pulsed devices mounted in a
large chamber I expected we could attain a 10-100 fold increase in beam
intensity and cooling, and by synchronizing with the pulsed lasers in
both the visible and ultraviolet be able to study a vast array of large
molecules, radicals, and clusters. Being the second apparatus we constructed,
it was called "AP2".
With AP2 we quickly succeeded in setting the world's record for rotational
cooling of a polyatomic molecule (0.17 K). We invented resonant two-photon
ionization (R2PI) with time of flight mass spectrometric detection as
a means of probing the spectrum of molecules in the supersonic beam. We
used this to probe the structure and molecular dynamics of large aromatic
molecules, particularly focussing on the question of intramolecular vibrational
redistribution. We also developed a means of producing fragments of polyatomic
molecules (free radicals such as benzyl and methoxy) by directing a pulsed
laser into a specially designed pulsed supersonic nozzle, and studying
these cooled in the supersonic beam.
In the late 1970s in collaboration with Andrew Kaldor and his group at
Exxon we had extended the capabilities of AP2 so that we could study a
large uranium containing molecule (a hexafluoroacetylacetonate-, tetahydrofurancomplexed
form of UO2). These were the days of the oil crisis, when there was widespread
belief that nuclear fission using uranium was going to be the only long-term
alternative. Exxon was working intensely on laser-based isotope separation
schemes, and Kaldor was heading up a group to pursue the molecular route.
Our experiment on AP2 ultimately revealed a beautiful sharpening of the
infrared multiphoton dissociation spectrum of this volatile UO2
complex cooled in the supersonic beam, just what Exxon was looking for.
Unfortunately, we began to succeed with these experiments only after the
nuclear release "event" at Three Mile Island on March 28, 1979.
Within a year, Exxon made a corporate level decision to get out of the
isotope separation business. But Kaldor had become so impressed with the
capabilities of AP2 that he wanted his own at the corporate laboratories
in Linden in any event. Under contract to Exxon, we developed a smaller
version of the apparatus, and built two versions. One was kept at Rice
and lived on for many years with a very productive science history. Logically,
it was called AP3. The clone of AP3 was shipped to Exxon in late 1982.
After a few years of intensive research we found a way to use a pulsed
laser directed into a nozzle to vaporize any material, allowing for the
first time the atoms of any element in the periodic table to be produced
cold in a supersonic beam. Most importantly, we developed a way to control
the clustering of these atoms to small aggregates, which then were cooled
in the supersonic expansion. Now for the first time it was possible to
roam the periodic table and make detailed study of the properties of nanometer-scale
particles consisting of a precise number of atoms. The field of metal
and semiconductor cluster beams was born. We shipped Exxon this new accessory
to their AP3 clone, and both groups then rapidly began to develop the
new field.
As is now well known, the Kaldor group was the first to put carbon in
a laser vaporization cluster beam apparatus, and see the amazing even-numbered
distribution of carbon clusters that we now know to be the fullerenes.
Within a year we repeated the same experiment, but now on an improved
version of AP2 that had been modified for the study of semiconductor clusters.
The story of what we discovered on this apparatus in September of 1985
has been told many times.
The subsequent development of my research in metal and semiconductor clusters,
and the fullerenes is too involved to recount here. Increasingly, the
tubular variant of the fullerenes has dominated our activities. Now our
motto is "if it ain't tubes, we don't do it". We are convinced
that major new technologies will be developed over the coming decades
from fullerene tubes, fibers, and cables, and we are moving as fast as
possible to bring this all to life.
Several years ago AP2 was dismantled and sold off in pieces to other research
groups, and the main chamber where the first pulsed nozzle experiments
were performed was sold off to a scrap metal dealer along the Houston
Ship Channel. Now there are no supersonic beam machines of any type in
the laboratory. Times change.
But life and science go on.
From
Les Prix Nobel 1996.
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