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coupling under the previous set of Heisenberg exchange coupling constants. Plotted on the vertical axis is the autocorrelation 〈 O ( k )$_{±}$ · O ( − k )$_{±}$ 〉$_{0}$ of the order parameter 

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over the groundstate normalized to its value in the true ferromagnetic state, 〈 O (0)$_{+}$ · O (0)$_{+}$ 〉$_{0}$ = 16 · 17 ¯ h $^{2}$. The relation to the ordered magnetic moment per iron atom, µ ( ± , k ), given there is obtained from the identity | 16 µ ( ± , k ) | 2 = (2 µ$_{B}$/ ¯ h ) $^{2}$〈 O ( k )$_{±}$ · O ( − k )$_{±}$ 〉$_{0}$ that is valid over the 4 by 4 square lattice of spin-1 iron atoms. The top graph in Fig. 7 displays how the square of the ordered moment for true cSDW order (+) decays with decreasing Hund’s rule coupling. It notably accounts for the low ordered moment that is observed by elastic neutron diffraction in an undoped parent compound to the recently discovered ferro- pnictide high- T$_{c}$ superconductors. 2 Also shown there is how hidden ferromagnetic order is 

