| Abstract: | Until now, solids with strongly correlated electrons can be treated only by model Hamiltonians. Even then a calculation of spectral densities is not simple, because the strong Coulomb interactions prevent us from treating correlations perturbatively. We show that projection and partitioning techniques are a very valuable tool here. The method is applied to computations of the density of states of transition metals, in particular, Ni. Here, the band narrowing and the sattlite peak at 6 eV due to correlations are reproduced. A second application concerns the spectral density of doped and undoped Cu(SINGLE BOND)O planes which are part of the high-Tc superconducting materials. © 1997 John Wiley & Sons, Inc. J Quant Chem 63: 645–653, 1997 |
