William Draper Harkins (December 28, 1873 – March 7, 1951) was an American physical

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe ...

, noted for his contributions to

surface chemistry Surface science is the study of physical and chemical phenomena that occur at the interface of two phases, including solid–liquid interfaces, solid– gas interfaces, solid–vacuum interfaces, and liquid– gas interfaces. It includes the f ...

and

nuclear chemistry Nuclear chemistry is the sub-field of chemistry dealing with radioactivity, nuclear processes, and transformations in the nuclei of atoms, such as nuclear transmutation and nuclear properties. It is the chemistry of radioactive elements such a ...

. Harkins researched the structure of the

atomic nucleus The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom, discovered in 1911 by Ernest Rutherford based on the 1909 Geiger–Marsden experiments, Geiger–Marsden gold foil experiment. After th ...

and was the first to propose the principle of

nuclear fusion Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles (neutrons or protons). The difference in mass between the reactants and products is manifest ...

, four years before

Jean Baptiste Perrin Jean Baptiste Perrin (30 September 1870 – 17 April 1942) was a French physicist who, in his studies of the Brownian motion of minute particles suspended in liquids (sedimentation equilibrium), verified Albert Einstein’s explanation of this p ...

published his theory in 1919-20. His findings enabled, among other things, the development of the

H-bomb A thermonuclear weapon, fusion weapon or hydrogen bomb (H bomb) is a second-generation nuclear weapon design. Its greater sophistication affords it vastly greater destructive power than first-generation nuclear bombs, a more compact size, a lowe ...

. As a visiting professor with

Fritz Haber Fritz Haber (; 9 December 186829 January 1934) was a German chemist who received the Nobel Prize in Chemistry in 1918 for his invention of the Haber–Bosch process, a method used in industry to synthesize ammonia from nitrogen gas and hydroge ...

in 1909, he was introduced to the study of surface tension, and he began work on the theory of solutions and solubility during a visit to MIT in 1909-1910. Harkins was born in

Titusville, Pennsylvania Titusville is a city in the far eastern corner of Crawford County, Pennsylvania, United States. The population was 5,601 at the 2010 census and an estimated 5,158 in 2019. Titusville is known as the birthplace of the American oil industry and f ...

, and graduated with a PhD from Stanford University in 1907. He subsequently taught chemistry at the

University of Montana The University of Montana (UM) is a public research university in Missoula, Montana. UM is a flagship institution of the Montana University System and its second largest campus. UM reported 10,962 undergraduate and graduate students in the fal ...

from 1900 to 1912, and then spent the rest of his career at the

University of Chicago The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private university, private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park, Chicago, Hyde Park neighborhood. The University of Chic ...

. Harkins correctly predicted the existence of the

neutron The neutron is a subatomic particle, symbol or , which has a neutral (not positive or negative) charge, and a mass slightly greater than that of a proton. Protons and neutrons constitute the nuclei of atoms. Since protons and neutrons behav ...

in 1920 (as a proton–electron complex) and was the first to use the word "neutron" in connection with the atomic nucleus. The neutron was detected experimentally by

James Chadwick Sir James Chadwick, (20 October 1891 – 24 July 1974) was an English physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932. In 1941, he wrote the final draft of the MAUD Report, which insp ...

in 1932. In the beginning of the 1930s, Harkins built a

cyclotron A cyclotron is a type of particle accelerator invented by Ernest O. Lawrence in 1929–1930 at the University of California, Berkeley, and patented in 1932. Lawrence, Ernest O. ''Method and apparatus for the acceleration of ions'', filed: J ...

. From experiments with this, he concluded that the

sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared rad ...

might be powered by nuclear fusion. Among other University of Chicago scientists who made use of this cyclotron was

Enrico Fermi Enrico Fermi (; 29 September 1901 – 28 November 1954) was an Italian (later naturalized American) physicist and the creator of the world's first nuclear reactor, the Chicago Pile-1. He has been called the "architect of the nuclear age" an ...

, who performed neutron diffusion experiments. Since 1978, the magnet yoke of the cyclotron Harkins built has been on display at

Fermilab Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a United States Department of Energy United States Department of Energy National Labs, national laboratory specializing in high-energy parti ...

. Among his students were

Robert Mulliken Robert Sanderson Mulliken Note Longuet-Higgins' amusing title for reference B238 1965 on page 354 of this Biographical Memoir. The title should be "Selected papers of Robert S Mulliken." (June 7, 1896 – October 31, 1986) was an American ph ...

, Lyle Benjamin Borst, Calvin Souther Fuller,

Martin Kamen Martin David Kamen (August 27, 1913, Toronto – August 31, 2002, Montecito, California) was an American chemist who, together with Sam Ruben, co-discovered the synthesis of the isotope carbon-14 on February 27, 1940, at the University of ...

, Henry W. Newson, Samuel Allison, and Robert James Moon, Jr. (1911–1989). Harkins died in

Chicago (''City in a Garden''); I Will , image_map = , map_caption = Interactive Map of Chicago , coordinates = , coordinates_footnotes = , subdivision_type = List of sovereign states, Count ...

. He is buried at

Oak Woods Cemetery Oak Woods Cemetery is a large lawn cemetery in Chicago, Illinois. Located at 1035 E. 67th Street, in the Greater Grand Crossing area of Chicago's South Side. Established on February 12, 1853, it covers . Oak Woods is the final resting place of ...

References

External links

William Draper Harkins Academic Genealogy and List of PhD Students

Guide to the William D. Harkins Papers 1877-1988
at th
University of Chicago Special Collections Research Center
{{DEFAULTSORT:Harkins, William Draper 1873 births 1951 deaths People from Titusville, Pennsylvania American chemists University of Montana faculty University of Chicago faculty Stanford University alumni People involved with the periodic table