Jack H. Freed, Cornell University professor of chemistry, has been awarded the 1997 Irving Langmuir Prize in Chemical Physics by the American Physical Society (APS).

The APS honored Freed, according to the society, "For his development of new magnetic resonance methods and theory, including computational algorithms for the stochastic Liouville equation, time-domain electron spin resonance methods for the study of molecular dynamics in liquids, applications of ESR to surface science, and the discovery of nuclear spin waves in spin-polarized H atoms."

Freed will receive the award at the APS annual meeting March 18 in Washington, D.C.

The research for which Freed earned the award was principally for his development of sophisticated theoretical and experimental electron spin resonance (ESR) techniques to understand molecular motions in liquids of varying complexity, such as liquid crystals in membranes and macromolecules. These techniques elucidate how molecules move, react and interact with one another.

The molecules are characterized by having an unpaired electron spin, but typically are stable. The interpretation of these ESR signals in terms of molecular dynamics had posed a major theoretical challenge, which Freed overcame with new and powerful algorithms. In recent years he has developed ESR methods to study directly the time evolution of these spin-bearing molecules, providing enhanced detail about these complex motions. He is applying these methods to clarify complex modes of internal and overall molecular reorientation that characterizes large molecules, such as proteins and polymers, and to better understand collective processes in liquid crystals, glassy liquids, on surfaces and in biological membranes.

Freed was further cited for his research on nuclear spin waves in spin-polarized hydrogen atoms, a collaborative investigation with David Lee, Cornell professor of physics and 1996 Nobel laureate in physics. They demonstrated that while hydrogen atoms at ultra-low temperatures (around 0.1 degree above absolute zero) behave randomly as an ideal gas, when their nuclear spins become oriented in the same direction, these same atoms exhibit long-range cooperative quantum effects. In short, the nuclear spins collectively behave in a cooperative fashion even while individual atoms behave randomly.

Freed is a fellow of the American Physical Society, a member of the American Chemical Society and a fellow of the American Academy of Arts and Sciences. He has served on the editorial boards of the Journal of Physical Chemistry, the Journal of Chemical Physics and of Chemical Physics Letters. He has been an Alfred P. Sloan Foundation Fellow and a John Simon Guggenheim Memorial Fellow. He received the ACS Buck-Whitney Award, the Bruker Award of the Chemical Society, U.K., and the Gold Medal Award of the International Electron Spin Resonance Society.

The Langmuir Prize was established in 1964 to recognize and encourage outstanding interdisciplinary research in chemistry and physics. It is awarded to a chemist or a physicist in alternating years.