Theory of Magnetic and Structural Ordering in Iron,

In this letter we assess the accuracy of the LSDA in describing the magnetic and structural ordering in 3d transition metals, based on total energy calculations for fcc and bcc iron as a function of volume and type of magnetic order. The local spin density approximation LSDA in describing the magnetic and structural ordering in iron is tested based on a series of total energy calculations using the general potential LAPW linearized augmented plane wave method. We find that ferromagnetism is stable in the bcc phase, while antiferromagnetism, which is degenerate with the nonmagnetic state, is stable in the fcc phase. However, our results show that the fcc phase is 867 K lower in energy than the bcc phase, which indicates a fundamental deficiency of LSDA in describing the magnetic interactions in transition metals.