Date of Award

6-2004

Degree Name

Doctor of Philosophy

Department

Physics

First Advisor

Dr. Clement Burns

Second Advisor

Dr. Lisa Paulius

Third Advisor

Dr. Arthur McGurn

Fourth Advisor

Dr. Harald Sinn

Abstract

In this work, inelastic x-ray scattering was used to measure the ionic collective excitations of a metal-ammonia system and the atomic form factor of lithium in a single crystal. For lithium and sodium ammonia systems, the measurements were carried out for different metal concentrations (lithium-ammonia with 2 0 , 16, and 13 mole percent metal [MPM] at T'=240K and sodium-ammonia with 18, 14, and 10 MPM at T=222K). These data were analyzed to determine the acoustic collective excitation dispersion relation and the linewidth. Deviations from the Bohm-Staver model for electron-ion coupling are discussed for the low electronic densities. For the lithium single crystal, the measured phonon intensities and energy were used to extract the atomic form factor of lithium at small momentum transfer, which is not accessible with other techniques. The measurement shows deviation from the free-atom form factor.

Access Setting

Dissertation-Open Access

Share

COinS