ParamagneticsusceptibilityofBCCferrite(a-Fe)andofcementite(Fe3C),wascalculatedinatemperaturerangeabovetheCuriepoint,usingadensityfunctional-basedmethodinconjunctionwithstatisticalapproximations.Theelectronicstructureandthemagneticenergyofbothsystemswerecalculatedusingthefullpotentiallinearaugmentedplanewave(FPLAPW)methodasimplementedintheWien2kCode.ThetemperatureeffectwascapturedbyintroducingtheBoltzmannstatisticaldistributiontodescribetheorientation