Dynamics of valence fluctuating rare earth compounds

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1985

OSTI ID:5275945

Cox, D L

This thesis reports on calculations of dynamical properties for valence fluctuating rare earth compounds based upon the degenerate Anderson Hamiltonian for magnetic impurities in metals. The main theme in this document is of the viability of the narrow many body Kondo resonance for providing a unifying account of the experimental results for valence fluctuators. Exploiting a recently developed self-consistent perturbation theory, numerical calculations were made of (i) transport properties for Ce impurities in metals, (ii) finite temperature photoemission spectra for Ce and Yb valence fluctuating compounds, and (iii) magnetic relaxation rates for valence-fluctuating Ce compounds. A rigorous calibration of the calculation method is provided by successful comparison of calculated thermodynamic quantities with exact Bethe Ansatz and Fermi Liquid theory results. The pathology known to exist for this self-consistent approach for low frequencies and temperatures is examined, and it is shown that many reliable results can be extracted despite the pathology. The possibility of phonon-assisted conduction electron scattering into the 4f Kondo resonance is examined, and is shown to be capable of reproducing the scale of measure resistivity, thermopower, and infrared absorptivity of concentrated valence fluctuating systems.

• Research Organization: Cornell Univ., Ithaca, NY (USA)
• OSTI ID: 5275945
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
CERIUM
ELEMENTS
IMPURITIES
KONDO EFFECT
METALS
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
RARE EARTHS
THERMODYNAMIC PROPERTIES
VALENCE
VARIATIONS