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Harden Marsden McConnell

Harden Marsden McConnell (Stanford University)

Harden Marsden McConnell

Robert Eckles Swain Professor of Chemistry
Department Chair, Department of Chemistry (1989-1993)


A leading 20th-century physical and biophysical chemist known for incisive contributions in both theory and experiment, Harden Marsden McConnell is also remembered as a kind colleague and dedicated mentor. Over his career, he significantly advanced understanding of magnetic resonance, cell membrane biophysics and immunology. His early work elucidated how the electronic structure of molecules contributes to electron spin and nuclear magnetic resonance (ESR and NMR) spectra. He developed the spin labeling technique, using free-radical labels with ESR spectroscopy to reveal protein and lipid membrane structure and kinetics. Leveraging this and related work, Professor McConnel and colleagues founded Molecular Devices, Inc. in 1983, to develop tools to study cellular response. His later career focused on biophysical studies of membranes, antibodies and molecules of the major histocompatibility complex.

Born in Richmond, Virginia in 1927, Professor McConnell completed his undergraduate studies at George Washington University (BS 1947). His doctoral research in chemistry guided by Norman Davidson at the California Institute of Technology (PhD 1951) focused on optical interaction absorption, a phenomenon of higher-than-predicted light absorption by two ion species in solution. After graduation, he studied charge transfer processes during postdoctoral research under physicist and chemist Robert Mulliken at the University of Chicago. He returned to the West Coast to pursue studies of nuclear magnetic resonance spectral characteristics at the Shell Development Company in Emeryville, California, before joining the Caltech faculty in 1956. Starting as assistant professor, he rose to associate professor in 1959 and full professor in 1959. He was recruited to Stanford in 1964. Here, he continued explorations into stable free-radicals that led to the spin labeling technique, and conducted research into membrane dynamics and proteins of the immune system, which he continued even after his official retirement to emeritus status.

Memorial Resolution: Harden Marsden McConnell

Obituary, Stanford Report

Message from the Chemistry Department Chair

The Research Studies of Harden McConnell

Honors & Awards

Welch Award in Chemistry (2002)
Award in Surface Chemistry, American Chemical Society (1997)
Peter Debye Award in Physical Chemistry, American Chemical Society (1990)
National Medal of Science in Chemistry (1989)
U.S. National Academy of Sciences Award in Chemical Sciences (1988)
Wolf Prize (shared with Herbert S. Gutowsky and John S. Waugh) (1984)
Fellow, American Association for the Advancement of Science (1982)
Irving Langmuir Award in Chemical Physics, American Chemical Society (1972)
Member, National Academy of Sciences (1965)
ACS Award in Pure Chemistry (1962)

Professional Education

PhD, Chemistry, California Institute of Technology (1951)
BS, George Washington University (1947)