Stoner enhancement factor

Stoner enhancement factor). This solution is evidently unstable when ... 

However, the intra-atomic Coulomb interaction Uf.f affects the dynamics of f spin and f charge in different ways while the spin fluctuation propagator x(q, co) is enhanced by a factor (1 - U fX°(q, co)) which may exhibit a phase transition as Uy is increased, the charge fluctuation propagator C(q, co) is depressed by a factor (1 -H UffC°(q, co)) In the case of light actinide materials no evidence of charge fluctuation has been found. Most of the theoretical effort for the concentrated case (by opposition to the dilute one-impurity limit) has been done within the Fermi hquid theory Main practical results are a T term in electrical resistivity, scaled to order T/T f where T f is the characteristic spin fluctuation temperature (which is of the order - Tp/S where S is the Stoner enhancement factor (S = 1/1 — IN((iF)) and Tp A/ks is the Fermi temperature of the narrow band). 

Xo, Xs-o and Xs are orbital, spin-orbit and spin contributions, S is the Stoner enhancement factor (see Sect. Ill of this chapter). Xs, Xo and Xs-o are given by ... 

Table 7. Stoner enhancement factor S determination for light actinide metals...

To summarize, we again want to make a sharp distinction between the enhancement in nearly ferromagnetic metals like Ni3Al, where the Stoner enhancement factor can increase x without limit but not dx/dT or y, and the enhancement in nearly antiferromagnetic metals to be discussed in Chapter 4, where x> V and dx/dT are all enhanced. In the former case, all models involve either a non-integral number of electrons in the band or degenerate orbitals. In the latter, two electrons on the same atom necessarily have antiparallel spins. 

Here S is the so-called Stoner enhancement factor, usually written as... 

In this formalism, the many-body effects are incorporated through the Stoner enhancement factor... 

The use of Xo indicates that the so-called Stoner enhancement factor has not been included (the toner theory is a mean-field theory for itinerant electrons). In Equation (3 3), is the averaged value of the varying D over the particles, Xyv is the Van Vleck paramagnetism, and Xdia is the Langevin (or Larmor) diamagnetism. 

Calculated LMTO charges (by I values), Qi, the total density of states at Ep, iV( p) Stoner enhancement factor, S, and the total energy... 

S Stoner enhancement factor magnetic propagation vector... 

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