1999/12/20 by Erik Koch, O. Gunnarsson, Olle Gunnarsson +1
Chemistry · Materials Science · Physics and Astronomy · #Advanced Chemical Physics Studies #Fullerene Chemistry and Applications #Organic and Molecular Conductors Research #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1016/s0010-4655(00)00023-0
published as Computer Physics Communications 127, 137 (2000) · 4 pages LaTeX with 4 eps figures; submitted to Computer Physics Communications, Proceedings of the CPP'99/Centennial Meeting, Atlanta, GA; additional material available at http://www.mpi-stuttgart.mpg.de/docs/ANDERSEN/fullerene/
arxiv created 1999/12/20 · openalex publication_date 2000/05/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study the Mott transition in Hubbard models with a degenerate band on different 3-dimensional lattices. While for a non-degenerate band only the half-filled system may exhibit a Mott transition, with degeneracy there can be a transition for any integer filling. We analyze the filling dependence of the Mott transition and find that Uc (the Hubbard interaction U at which the transition takes place) decreases away from half-filling. In addition we can change the lattice structure of the model. This allows us to study the influence of frustration on the Mott transition. We find that frustration increases Uc, compared to bipartite systems. The results were obtained from fixed-node diffusion Monte Carlo calculations using trial functions which allow us to systematically vary the magnetic character of the system. To gain a qualitative understanding of the results, we have developed simple hopping arguments that help to rationalize the doping dependence and the influence of frustration on the Mott transition. Choosing the model parameters to describe the doped Fullerides, we can make contact with experiment and understand why some of the Fullerides are metals, while others, which according to density functional theory should also be metallic, actually are insulators.