Clifford Glenwood Shull was born on September 23, 1915, in the Glenwood section of Pittsburgh, Pennsylvania. Along with his older brother and sister, Shull attended neighborhood schools, then enrolled in Schenley High School. At Schenley, a dynamic instructor sparked Shull's interest in physics, causing himto reconsider his initial ambition to be an aeronautical engineer. After graduating, he won a partial scholarship to the Carnegie Institute of Technology, now Carnegie Mellon University, and immersed himself in his studies. DuringShull's freshman year, however, his father died suddenly, precipitating notonly an emotional, but a financial crisis for the family. As a result, Shull's older brother, Perry, quit his job as an art teacher and ran their father'sbusiness until his younger sibling had graduated from college.
After receiving his B.A. from Carnegie, Shull entered the graduate physics program at New York University. Early on he became associated with the nuclearphysics research group and took part in several different experiments using particle accelerators. For his Ph.D. thesis he used the department's newly constructed Van de Graaff accelerator to determine whether or not electrons havea spin or polarization.
A month after receiving his Ph.D. from New York University, Shull accepted aresearch position at The Texas Company, now Texaco, in Beacon, New York. There, he used gas absorption as well as x-ray diffraction and scattering to analyze catalysts used in the production of high-performance aviation fuel. Thisresearch took on great importance following the entry of the United States into World War II. However, Shull, like many other young physicists of the time, was very interested in the Manhattan Project. He had seen several of his former university friends and professors join in the race to produce the firstnuclear weapon and longed to take part as well. Yet when an attempt was madeto recruit him, The Texas Company blocked his way, eventually convincing a government manpower board that his research for them was more crucial to the wartime effort.
At the end of the war Shull was free to pursue his interest in nuclear physics, and in 1946 he left The Texas Company for the Clinton Laboratory in Oak Ridge, Tennessee. Eventually renamed the Oak Ridge National Laboratory, it hadbeen one of the top-secret sites of the Manhattan Project, and its nuclear reactor had supplied a significant portion of the plutonium used in the atomicbombs dropped on Hiroshima and Nagasaki. At the time Shull arrived, the laboratory's administrators had begun to shift its focus from military to civilianuses, and he was assigned to work with Ernest Wollan. Wollan, who had been with the laboratory since its inception, had begun to investigate how the neutron beams produced by the reactor could be used to analyze the structure of matter. Over the next decade, the two scientists developed a method of neutrondiffraction that eventually became the foundation of an entirely new branchof physics research.
Shull and Wollan discovered that neutrons, upon hitting the atoms within a fluid or solid sample, ricochet in a characteristic fashion. Specifically, theangle at which the neutrons are deflected shows how the atoms are arranged. In other words, neutron scattering effectively determines the atomic structureof a sample. Neutron scattering was a truly revolutionary discovery, openingnew avenues of research as it shed new light on important substances, such as the element hydrogen, that had been resistant to earlier methods of analysis. It wasn't until 1994 that the Nobel committee recognized the work of Shulland Wollan, awarding the Nobel Prize in physics to Shull (and Bertram Brockhouse). Sadly, Wollan had died in 1984.
Shull left the Oak Ridge National Laboratory in 1955 to become a professor ofphysics at the Massachusetts Institute of Technology, retiring as emeritus professor in 1986.
Shull died on March 31, 2001, in Medford, Massachusetts. He was 85.
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