Harold Walter Kroto

British chemist Sir Harold Walter Kroto (born 1939) received the 1996 Nobel Prize for Chemistry, along with Robert F. Curl Jr., and Richard E. Smalley. The scientists were honored for the discovery of fullerenes, a new form of carbon called Carbon 60. The discovery opened the way for new branches in chemistry and helped to advance the area of nanoscience and nanotechnology. Kroto was knighted in 1996.

Kroto was born on October 7, 1939, in Wisbech, Cambridgeshire, England, to Heinz and Edith Krotoschiner (his father changed the family name to Kroto in 1955). His parents were born in Berlin, Germany, and were compelled to flee to England in 1937 after the rise of the Nazi Party.

In 1940, during World War II, the British government sent Kroto's father to an internment camp on the Isle of Man, as he was considered an enemy alien. Kroto then moved with his mother to Bolton, in Lanchashire, where he was raised.

Later, Kroto would affectionately describe his parents as "eccentric," but, on a much more serious note, he expressed great compassion for their plight. "I always felt that my parents had a really raw deal, as did almost everyone born in Europe at the turn of the Century," he recalled when he received his Nobel Prize in 1996. "The First World War took place while they were teenagers, then the Depression struck and Hitler came to power while they were young adults. They had to leave their home country and then the Second World War broke out and they had to leave their home again. When my father was 45 he had to find a new profession, when he was 55 he set up his business again."

Kroto indicated that his father had early ambitions to become a dress designer but ended up operating a graphics business that printed images on balloons. Kroto's parents' ordeal no doubt influenced the values and philosophies that he adopted as an adult. A self-described humanist and "devout atheist," he had difficulty accepting the concept of a "humanitarian" God.

Kroto would also come to reject the notion that the "good" of the community must override individual rights. That notion, he believed, only justified the oppression of individuals by the state. As such, he would later become a supporter of Amnesty International.

Studied Chemistry in College

As a boy, Kroto demonstrated an interest in physics, math, and especially chemistry. He also played sports, concentrating on gymnastics and tennis. As his interest in chemistry grew, he was encouraged by a grade school teacher to enroll at the University of Sheffield, the British educational institution that reputably had the best chemistry department in the United Kingdom.

In 1961 Kroto graduated from Sheffield with a degree in chemistry. In 1963 he married Margaret Henrietta Hunter, and the couple had two sons. The following year Kroto earned his Ph.D. at the University of Sussex, where his post-graduate work involved high-resolution electronic spectra of free radicals produced by flash photolysis—chemical decomposition by the action of radiant energy. At Sussex, while still keenly interested in chemistry, Kroto became fascinated by quantum mechanics when he was introduced to spectroscopy. "It was fascinating to see spectroscopic band patterns which showed that molecules could count," he recalled in 1996.

In 1964, after receiving his Ph.D., Kroto received several job offers. After conferring with his wife, he accepted a postdoctoral position at the National Research Council (NRC) in Ottawa, Canada, as both he and his wife wanted to experience life abroad. Kroto described the NRC as "a mecca of spectroscopy" and the only international research facility at the time that was deemed successful.

In 1966 Kroto received an offer for another postdoctoral position, this time at the University of Sussex in the United Kingdom. However, Kroto and his wife wanted to live in the United States, so he accepted another position at Bell Laboratories in Murray Hill, New Jersey, where he conducted research in quantum chemistry, specifically on liquid phase interactions by laser Raman spectroscopy. After a year Kroto accepted the position at Sussex, and began teaching and conducting research at the university in 1967. He became a full professor in 1985 and a Royal Research Professor in 1991.

Became Involved in Carbon Chain Research

During the 1970s Kroto was engaged in a research program that he initiated at Sussex, designed to detect carbon chains existing in interstellar atmospheres and interstellar gas clouds. He collaborated with scientists from the NRC to find such molecules, and during research conducted between 1975 and 1978, they indeed found several carbon chains. In carrying out this research, Kroto employed microwave spectroscopy, a science that can be used to analyze gas in space. This led to his discovery of carbon chains residing in the atmospheres of carbon-rich giant stars and gas clouds. Kroto hypothesized that the chains had been formed in stellar atmospheres and not in gas clouds, but he did not know exactly how the chains were formed. His search for an answer would result in the discovery of the Carbon-60, or C₆₀, molecule.

In 1984 Kroto traveled to Rice University in Houston, Texas, to further investigate the formation of carbon chains. Specifically, he wanted to study the vaporization of carbon to determine how the chains formed. He chose the University because he became aware of the studies being conducted by researchers Richard Smalley and Robert Curl in laser spectroscopy. At Rice, Smalley had developed the laser-supersonic cluster beam apparatus, an instrument that could vaporize just about any known material, and the device was then used to analyze the clusters of atoms or molecules resulting from the vaporization. Kroto felt that he could use the technology to replicate the temperatures in space necessary to form the carbon chains. Previously, Smalley and Curl, who would later receive the 1996 Nobel Prize in Chemistry with Kroto, had been using laser spectroscopy to examine semiconductors such as silicon and germanium, but they had not looked at simple carbon.

However, in a series of experiments conducted in September of 1985, Kroto, Smalley and Curl directed the laser at graphite. They vaporized the graphite in an atmosphere of helium, in the process generating clusters of carbon atoms and discovering a molecule that had 60 carbon atoms. The discovery surprised them, as carbon had been known to have only two molecular forms, diamond and graphite. The new form of carbon had a complex, highly symmetrical arrangement that resembled a soccer ball or, more precisely, the geodesic dome, a structure that had been popularized by inventor and architect R. Buckminster Fuller. Because of its resemblance to the dome, the scientists named the new carbon structure buckminsterfullerene, which they later shortened to fullerene. They also called it the "buckyball" (Fuller's nickname was "Bucky."). The discovery would lead to a new branch of chemistry developed to manipulate the fullerene structure.

The discovery compelled Kroto to suspend his dream of building a studio to do scientific graphic design. He had a long term interest in graphic design and had been doing it semi-professionally for about a year, and he perceived how recent advances in computer technology had substantially advanced the artistic potential of graphic design. However, he now deemed it much more important to explore the consequences of the C₆₀ discovery.

Kroto then proceeded forward at full throttle into research. In 1991 he was awarded a Royal Society Research Professorship, which freed him from teaching and enabled him to fully concentrate on his experiments.

Received Nobel Prize

Kroto, Smalley and Curl became the first scientists to completely identify and then stabilize Carbon-60, and the Royal Swedish Academy of Sciences awarded them the 1996 Nobel Prize in Chemistry. In addition, as a result of his important discovery and the subsequent Nobel Prize, Kroto was knighted. There was a bit of irony attached to the British honor and the Nobel award. Only two hours before it was announced that Kroto had won the Nobel Prize, the British government had turned down his request for research funding. The research would have involved the same work that earned him the Nobel Prize in the first place.

That may be one of the reasons why Kroto was somewhat ambivalent about winning the Nobel Prize. Another reason, which he stated in 1996, was that he felt the work of the graduate students involved in the 1985 research, J.R. Heath and S.C. O'Brien, did not receive adequate recognition. Likewise, he felt that the accomplishments (extracting C₆₀) of Wolfgang Krätschmer and Don Huffman and their students Kostas Fostiropoulos and Lowell Lamb were not sufficiently recognized. Moreover, Kroto never felt he needed awards to justify or validate his work or to provide him with a sense of satisfaction.

Nevertheless, his discovery was a remarkable achievement with substantial impact. The Royal Swedish Academy of Sciences recognized its implications for the natural sciences. "The discovery of fullerenes has expanded our knowledge and changed our thinking in chemistry and physics," the Academy stated, when it honored Kroto and his colleagues. "It has given us new hypotheses on the occurrence of carbon in the universe. It has also led us to discover small quantities of fullerenes in geological formations. Fullerenes are probably present in much larger amounts on earth than previously believed."

Further, the Academy noted, "From a theoretical viewpoint, the discovery of the fullerenes has influenced our conception of such widely separated scientific problems as the galactic carbon cycle and classical aromaticity, a keystone of theoretical chemistry."

Moved Back to America

Following his Nobel Prize, Kroto continued conducting fundamental research on the fullerene, examining its basic chemistry and how it has changed the way the scientific world perceives carbon-based materials. On July 14, 2004, Kroto received the Royal Society of London's Copley Medal "in recognition of his seminal contributions to understanding the fundamental dynamics of carbon chain molecules, leading to the detection of these species (polyynes) in the interstellar medium by radioastronomy, and thence to the genesis of a new era in carbon science." The medal is the highest award the Society presents.

Later that year, he left Sussex University to join the faculty of Florida State University in Tallahassee, Florida. Kroto left Britain because it would have been difficult to raise funds for his work after he reached retirement age in October of 2004. By joining Florida State, he was guaranteed funding for his research.

On April 25, 2006, Kroto was elected a member of the U.S. National Academy of Sciences, one of the highest honors that a scientist could receive.

Books

Notable Scientists: From 1900 to the Present, Gale Group, 2001.

World of Scientific Discovery, 2nd Edition. Gale Group, 1999.

Online

"The Nobel Prize in Chemistry 1996—Press Release," Nobelprize.org, http://www.nobelprize.org/nobel_prizes/chemistry/laureates/1996/press.html (December 20, 2006).

"Sir Harold Kroto, the Nobel Prize in Chemistry 1996—Autobiography," Nobelprize.org, http://www.nobelprize.org/nobel_prizes/chemistry/laureates/1996/kroto-autobio.html (December 20, 2006).

"Sir Harold Walter Kroto," Encyclopedia Britannica, http://www.search.eb.com/nobelprize/article-9003029 (December 20, 2006).