Manousakis, EfstratiosRen, JunMeng, ShengKaxiras, Efthimios2015-03-122010Manousakis, Efstratios, Jun Ren, Sheng Meng, and Efthimios Kaxiras. 2010. "Is the Nature of Magnetic Order in Copper-Oxides and in Iron-Pnictides Different?" Solid State Communications 150 (1-2): 62–65.0038-1098http://nrs.harvard.edu/urn-3:HUL.InstRepos:14121877We use the results of first-principles electronic structure calculations and a strong coupling perturbation approach, together with general theoretical arguments, to illustrate the differences in super-exchange interactions between the copper-oxides and iron-pnictides. We provide a possible explanation for the two magnetic ground states within the same theoretical foundation. Contrary to the emerging view that magnetic order in the iron-pnictides is of itinerant nature, we argue that the observed magnetic moment is small because of frustration introduced by the electrons of the Fe orbitals as they compete to impose their preferred magnetic ordering.en-USMagnetically ordered materialsElectronic band structureExchangeSuperexchangeJournal Article2015-03-1210.1016/j.ssc.2009.10.005