Band ferromagnetism

According to the spin fluctuations theory, the Curie temperature of the band ferromagnets is inversely proportional to the density of states in the subbands near the Fermi level, NT(Ef) and Nl(E ). The increase of the lattice parameters after the hydrogen atoms incorporation to the lattice induces the decrease of the degree of wave-function hybridization between the 3r/-electrons of Fe atoms and 5r/-electrons of rare-earth metal atoms. This in turn entails the decrease of density of states in both zones NT(Ef) and Ni(EF). 

Fig. 80. Simplified density of states curve for metallic chromium. Energy scale is referred to bottom of s-p band. The Fermi level relative to the d bands is also shown for b.c.c. Ti, V, and Mn given the same relative positions of d and s-p bands. Ferromagnetic, simple-cubic sublattices are coupled antiferro-magnetically in b.c.c. Cr-Mn alloys.

Band discontinuity, heterojunction, 254f, 425ff Band ferromagnetism, 52l -525 Band gap... 

Usami and Moriya (1980) and Moriya and Takahashi (1978b) applied an extension of the theory of Moriya and Takahashi (1978a) to narrow band ferromagnetism. 

Slater, J. C., Revs. Modern Phys. 25, 199, "Ferromagnetism and the band theory."... 

---