Abstract
The properties of correlated electrons in small clusters having N ≤ 8 atoms are studied in the framework of the single-band Hubbard Hamiltonian. The many-body ground state is solved exactly by means of Lanczos numerical diagonalization method. A full geometry optimization is performed by considering all possible non-equivalent cluster structures with fixed nearest-neighbors bond-lengths. The most stable structure and the total spin S are obtained as a function of the Coulomb interaction strength U and number of electrons v (1 ≤ v ≤ 2N). The resulting physical behavior is discussed together with the built-in limitations of the model.
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© 1994 Springer Science+Business Media New York
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Pastor, G.M., Hirsch, R., Mühlschlegel, B. (1994). Theoretical Study of Electron Correlations in Small Clusters. In: Morán-López, J.L., Sanchez, J.M. (eds) New Trends in Magnetism, Magnetic Materials, and Their Applications. Springer, Boston, MA. https://doi.org/10.1007/978-1-4899-1334-0_4
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