Harry Gray

Harry B. Gray is the Arnold O. Beckman Professor of Chemistry and Founding Director of the Beckman Institute in the Division of Chemistry and Chemical Engineering at the California Institute of Technology, where he joined the faculty in 1966. He earned a B.S. in chemistry from Western Kentucky University in 1957 and a Ph.D. in inorganic chemistry from Northwestern University in 1960. Gray conducted postdoctoral research as an NSF Fellow at the University of Copenhagen from 1960 to 1961, followed by appointments at Columbia University as assistant professor from 1961 to 1963 and associate professor from 1963 to 1965. Upon arriving at Caltech, he shifted focus to the role of metals in living systems and served as Chairman of the Division of Chemistry and Chemical Engineering from 1978. His research in inorganic chemistry encompasses bioinorganic electron transfer chemistry, ligand field theory of metal-oxo multiple bonding, electronic structures of tetra-oxo complexes, the "oxo wall" between iron-ruthenium-osmium and cobalt-rhodium-iridium groups in the periodic table, redox-active coordinated ligands ("non-innocent ligands"), electron tunneling in proteins, long-range electron transfer via multiple hole-tunneling steps ("hole hopping"), biological electron transport and energy transduction, and protection of cells from oxidative damage through redox-active amino acid residues.

Gray's 1982 Journal of the American Chemical Society paper reported the first measurement of electron tunneling in a protein of known structure, profoundly influencing understanding of biological electron flow. His discoveries have launched widespread studies of non-innocent ligands as sensors, conductors, and catalysts, and revealed mechanisms for cellular protection. He has authored over 950 research papers and delivered named lectures on six continents and in all 50 U.S. states. Gray has mentored several hundred students and postdocs, including over 100 women, six of whom became presidents of universities. His honors include the National Medal of Science (1986), Priestley Medal (1991), Wolf Prize in Chemistry (2004), Welch Award in Chemistry (2009), Richards Medal (2014), and Cotton Medal (2018), seven American Chemical Society national awards, 22 honorary doctorates, and memberships in the National Academy of Sciences, American Academy of Arts and Sciences, American Philosophical Society, and foreign academies including the Royal Society.

Professional Email: hgray@caltech.edu