William Klemperer

William Klemperer
William Klemperer (captured by Stewart Novick, c. 1970)
Born	(1927-10-06)6 October 1927 New York City, US
Died	5 November 2017(2017-11-05) (aged 90)
Alma mater	Harvard University (A.B.), University of California, Berkeley (Ph.D.)
Scientific career
Fields	Chemist
Institutions	Harvard University
Doctoral advisor	George C. Pimentel

William A. Klemperer (October 6, 1927 – November 5, 2017) was an American chemist, chemical physicists and molecular spectroscopists. Klemperer is most widely known for introducing molecular beam methods into chemical physics research, greatly increasing the understanding of nonbonding interactions between atoms and molecules through development of the microwave spectroscopy of van der Waals molecules formed in supersonic expansions, pioneering astrochemistry, including developing the first gas phase chemical models of cold molecular clouds that predicted an abundance of the molecular HCO⁺ ion that was later confirmed by radio astronomy.^[1]