Spin disorder in paramagnetic fcc iron

From available information on the total entropy of fcc iron, its phonon density of states at 1428 K, and its electron density of states, the entropy due to disorder of the persistent spins in the paramagnetic state at 1428 K is estimated as SmagR=0.8±0.1. This should be compared with the entropy of completely disordered spins of magnitude Sₐ per atom, which would be SmagR=ln(2Sₐ+1)=1.2, if we take 2Sₐ=2.4 from band-structure calculations. This comparison indicates that there is very little correlation between the directions of the average magnetic moments at neighboring lattice sites.