Ralph Kronig

Ralph Kronig
Ralph de Laer Kronig (1904–1995)
Born10 March 1904 (1904-03-10)
Died16 November 1995 (1995-11-17) (aged 91)
NationalityGerman
CitizenshipUnited States
Germany
Alma materColumbia University
Known forDiscovery of particle spin
Kronig structure
Kronig–Penney model
Coster–Kronig transition
Kramers–Kronig relations
AwardsMax Planck Medal (1962)
Scientific career
InstitutionsColumbia University
TU Delft
Doctoral advisorAlbert Potter Wills
Other academic advisorsWolfgang Pauli

Ralph Kronig (10 March 1904 – 16 November 1995) was a German physicist. He is noted for the discovery of particle spin and for his theory of X-ray absorption spectroscopy. His theories include the Kronig–Penney model, the Coster–Kronig transition and the Kramers–Kronig relations.