NEUTRON DIFFRACTION STUDIES OF COORDINATION AND ORGANOMETALLIC COMPOUNDS. Thomas F. Koetzle, Chemistry Department, Brookhaven National Laboratory, P.O. Box 5000, Upton, NY 11973-5000 USA

In the 50 years since Shull and Wollan's pioneering experiments at Oak Ridge National Laboratory, neutron diffraction has been used to attack a wide range of structural problems in inorganic and organometallic chemistry. These studies exploit the unique properties of neutrons that make them a powerful probe and complement to x rays in crystallographic research. Neutrons are highly sensitive to hydrogen and light atoms in general, have the ability to reveal nuclear positions and mean displacements without bias from the effects of the electron distribution, can detect isotopic substitutions, and are sensitive probes of magnetism.

This lecture will concentrate on single-crystal neutron diffraction, and will illustrate the field with examples taken from work at both reactor and spallation neutron sources. Topics discussed will include structures of metal hydrogen compounds, use of deuterium labelling to investigate reaction mechanisms, structures of ice and gas clathrate hydrates, and studies of spin-density distributions in open-shell systems.

Acknowledgement: Research at Brookhaven National Laboratory was carried out under contract DE-AC02-76CH00016 with the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences.