The role of matrix elements in the calculation of the generalized susceptibilities χ(q→) of metals is discussed using the results of an augmented-plane-wave energy-band calculation for the eigenvalues and eigenfunctions of Sc metal. The inclusion of the oscillator strength matrix elements is found to significantly alter the structure obtained for χ(q→) in the constant-matrix-element approximation. The effect of local-field corrections on the phonon anomaly in Sc and the observed magnetic ordering of dilute rare-earth Sc alloys are described; in the latter case, a crude estimate of this effect is found to restore a (broad) peak in χ(q→) at q→[0,0,0.5(πc)], in good agreement with experiment.
ASJC Scopus subject areas
- Condensed Matter Physics