Ralph G. Pearson

Ralph G. Pearson
Professor Emeritus

Office Location

4619 PSB-N


Inorganic Chemistry


Dr. Pearson received his Ph.D. in 1943 from Northwestern University. He was on the Northwestern faculty until he came to UCSB in 1976. Dr. Pearson has been awarded the American Chemical Society's Award in Inorganic Chemistry, and he is a member of the National Academy of Science. Although Professor Pearson retired in 1989, he remains an active researcher in the Department in the field of theoretical inorganic chemistry.


Current Research

Mechanisms of chemical reactions; theory of chemical bonding; applications of density functional theory to chemistry.

My main field of research is in the application of the new concepts of absolute electronegativity and absolute hardness. These are the first and second derivatives, respectively, of a plot of electronic energy vs the number of electrons in a atom or molecule. These determine the direction of electron flow and the amount of charge transferred in a reaction between two molecules. They may be used to predict the rate of reaction, or in some cases, the coordinate bond energy. At equilibrium, chemical systems are in a state of maximum hardness.


Selected Research Publications

Pearson, RG Chemical hardness and density functional theory J CHEM SCI 117 (5): 369-377 SEP 2005.

Pearson, RG Self-consistent shielding in atoms and molecules INT J QUANTUM CHEM 101 (3): 239-245 2005.

Pearson, RG Improving the energies of approximate wave functions using the concepts of density functional theory INT J QUANTUM CHEM 86 (3): 273-279 JAN 20 2002.

Maximum Chemical and Physical Hardness, Ralph G. Pearson, J. Chem. Ed., 76, 267, (1999).

Electr5onic Properties of Some Inorganic Solids, Ralph G. Pearson, Inorg. Chim. Acta, 270, 252, (1998).