Magnetism near the Van Hove singularity
We study the phase diagrams of the s-band and d-band Hubbard model in two dimensions including electron correlations. While the ferromagnetic instability in the s-band case occurs only near the Van Hove singularity, ferromagnetism is more stable in the d-band model, and the values of the Stoner parameters in transition metals are reduced below their LDA values.(14 refs)