University of Illinois, Urbana-Champaign (MS), Alfred G. Redfield (March 11, 1929 – July 24, 2019) was an American physicist and biochemist.

IBM Watson Scientific Computing Laboratory hired him in 1955 and he taught at Columbia.While there he published his most important work, the Redfield Relaxation Equation.

[1] In 2007 he was recognized with the Russell Varian Prize for contributing the Redfield Relaxation Theory to the field of nuclear magnetic resonance.

[17] Redfield's original article published in the IBM Journal in 1957, and then in the first issue of Advanced Magnetic Resonance in 1965, "The Theory of Relaxation Processes" explained observations that molecules excited with RF in a magnetic field did not relax as expected in terms of classical thermodynamics, but could be explained in terms of quantum physics, yielding a semi-classic explanation of nuclear spin in metals.

Redfield's interests included discovering techniques to advance the practice of NMR for the purpose of nuclear induction spectroscopy, super conducting magnets, current regulator for inductive loads, practical demonstration and proof of theory, nuclear spin thermodynamics, rare spins in solids, two dimensional NMR efficiencies, computing and data processing, isotope labeling, nuclear Overhauser effect, proteins and their macromolecules in solution, phospholipid approaches.

This work later proved to be useful in the study of the physical and motional relationships between protons in large biological molecules, called macromolecules.

However, his genius was not limited to NMR; Redfield relaxation theory has been applied to statistical mechanical and spectroscopic systems throughout the physical sciences.

With X. Shi, et al. Modulation of Bacillus thuringiensis phosphatidylinositolspecific phospholipase C activity by mutations in the putative dimerization interface.