John Hasbrouck Van Vleck

He married Abigail Pearson in 1927. Both of them were important art collectors, particularly in the medium of Japanese woodblock prints (principally Ukiyo-e). Their marriage lasted more than five decades.

He died on October 27, 1980, at the age of 81.

John Hasbrouck Van Vleck was born in Middletown, Connecticut, March 13, 1899, as the only son of mathematician Edward Burr Van Vleck and his wife, Hester Laurence Raymond. His grandfather was the astronomer John Monroe Van Vleck.

He grew up in an intellectually stimulating environment and displayed proficiency in science and mathematics from a young age. He graduated with an A.B. degree from the University of Wisconsin–Madison in 1920.

Then he proceeded to Harvard University for graduate studies and earned a Ph.D. degree in 1922. His doctoral thesis was on the calculation of the binding energy of a certain model of the helium atom which he completed under the guidance of Professor Kemble, the one person in America at that time qualified to direct purely theoretical research in quantum atomic physics.

In 1923, John Hasbrouck Van Vleck was offered an assistant professorship at the University of Minnesota with purely graduate courses to teach. The young scientist was delighted at the opportunity as it allowed him ample time to devote to research.

Van Vleck conceived his correspondence principle for absorption in 1924. He demonstrated that in the limit of high quantum numbers there would be a correspondence between absorption by classical, multiple periodic systems, and by their quantum analogues. This was a very significant finding for that period.

During his career at Minnesota, he completed a report, ‘Quantum Principles and Line Spectra’ for the National Research Council. An immediate hit upon its publication, it quickly sold out its initial printing of 1,000 copies, and an additional 300 copies were printed in 1928.

He became a professor at the University of Wisconsin in 1928, a position he held until 1934. During this time he began writing his second book, ‘The Theory of Electric and Magnetic Susceptibilities’ which was published in 1932. The same year he also wrote his first paper on the crystal field theory.

In the mid-1930s, he moved to the Harvard University and remained there until his retirement in 1969. He served in a number of different positions at the university over the years: as chairman of the physics department (1945–49), dean of engineering and applied physics (1951–57), and Hollis professor of mathematics and natural philosophy (1951–69).

John Hasbrouck Van Vleck was a participant in the Manhattan Project, a research and development project that produced the first nuclear weapons during World War II. Along with other noted theoretical scientists, Van Vleck examined and developed the principles of atomic bomb design.

During the World War II, he worked on radar and demonstrated that that at about 1.25-centimeter wavelength water molecules in the atmosphere would lead to troublesome absorption and that at 0.5-centimeter wavelength there would be a similar absorption by oxygen molecules.