Accession Number : AD0605334

Title :   EXPERIMENTAL STUDY OF SPIN-LATTICE RELAXATION BY THE ORBACH PROCESS IN NEODYMIUM MAGNESIUM NITRATE.

Descriptive Note : Technical rept no. 6,

Corporate Author : KANSAS UNIV LAWRENCE

Personal Author(s) : Hoffman,J. T. ; Sapp,R. C.

Report Date : 25 AUG 1964

Pagination or Media Count : 1

Abstract : Measurement was made of the spin-lattice relaxation time of trivalent Nd ions in Nd-Mg nitrate by fitting Casimir-du Pre dispersion curves to the frequency dependence of the self-inductance of a coil into which the sample could be inserted. The difference in self-inductance, with and without the sample, was determined by a modified Owen bridge at liquid helium temperatures and in fields between zero and 1800 oe. In the 3.3-4.2K range the Orbach process dominates and is identified by its characteristic exponential inverse temperature variation. For H perpendicular to the crystal axis, good agreement was found with Orbach's theory for the magnetic field dependence of this process. As by-products of the experiments, determination was also made of the magnetic specific heat constant and the temperature-independent susceptibility. (Author)

Descriptors :   (*PARAMAGNETIC MATERIALS, RELAXATION TIME), (*NEODYMIUM, PARAMAGNETIC RESONANCE), (*SINGLE CRYSTALS, PARAMAGNETIC RESONANCE), CRYSTAL LATTICES, NUCLEAR SPINS, NEODYMIUM COMPOUNDS, MAGNESIUM COMPOUNDS, NITRATES, MAGNETIC PROPERTIES, COILS, INDUCTANCE, ELECTRIC BRIDGES, MAGNETIC FIELDS, CRYOGENICS, SPECIFIC HEAT

Distribution Statement : APPROVED FOR PUBLIC RELEASE