Accession Number : AD0267071

Title :   THE INTERACTION OF PARAMAGNETIC IONS AND ALUMINUM NUCLEI IN RUBY

Corporate Author : COLORADO UNIV BOULDER ENGINEERING EXPERIMENT STATION

Personal Author(s) : VERBER,CARL M.

Report Date : JUL 1961

Pagination or Media Count : 1

Abstract : Th techniques of continuous and pulse nuclear magnetic resonance were used to study the aluminum nuclei in ruby crystals. Four commercially prepared samples having nominal chromium ion concentrations of 0.01, 0.1, 1.5, and 4% were investigated at 300, 78, 4, and 1.7 K. The line widths were found to be due to two major contributions. The mutual interaction of the aluminum nuclei contributed a constant broadening of about 7 gauss. The paramagnetic ions contributed a broadening which ranged from 0 to 42 ga ss as a function of temperature, concentration and static magnetic field. This dependence can be calculated by assuming that the chromium ions have an effective magnetic moment which is determined by the Boltzman average of the four spin states of the ion at each temperature considered. This indicates that the chromium ions are in good thermal contact with the lattice down to 1.7 K. The relaxation times were found to be a strong function of the chromium ion concentration. An effort was made to predict these times, using known values of the chromium relaxation times and existing theories in which the nuclear relaxation times are given in terms of the paramagnetic relaxation times. No agreement was found between theoretical and experimental values, and a revision of existing theories is indicated. (Author)

Descriptors :   *MASERS, *NUCLEAR PHYSICS, *QUANTUM THEORY, *RUBY, ALUMINUM, ATOMIC SPECTROSCOPY, CHROMIUM, CRYSTALS, DIFFUSION, IONS, MEASUREMENT, NUCLEAR MAGNETIC MOMENTS, NUCLEAR MAGNETIC RESONANCE, NUCLEI, PARAMAGNETIC RESONANCE, RELAXATION TIME, TEMPERATURE, THEORY

Distribution Statement : APPROVED FOR PUBLIC RELEASE