Correlations and the Magnetic Moment of MnSi
We have investigated the origin of the anomalously low measured moment of MnSi (0.4 μB / Mn) when compared to DFT calculations (1.0 μB / Mn) by adding a Hubbard-U. By treating the Hubbard-U as an adjustable parameter, we have found two ground state solutions. For low values of U, a high-moment solution is energetically favored with μ ≈ 1.0 μB / Mn. For U ≥ 0.5 Ry, the low-moment solution becomes favorable with a moment comparable to the experimental value. However, for any value of U, the calculation's predictions for the system under pressure do not agree with experiment. © 2007 Elsevier B.V. All rights reserved.