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The Peierls-Hubbard model at weak coupling

Michael Dzierzawa·Carmen Mocanu
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Abstract

We investigate the Peierls transition in the one-dimensional Peierls-Hubbard model at half filling in the adiabatic approximation for the lattice. Depending on the value of the electron-lattice coupling constant g the equilibrium dimerization can be either enhanced or suppressed by the Hubbard interaction U. Applying second order perturbation theory we determine the critical value g_c = 0.689348 below which the Hubbard interaction enhances the dimerization.

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Michael Dzierzawa, Carmen Mocanu. 2005-04-15. The Peierls-Hubbard model at weak coupling. https://doi.org/10.1088/0953-8984%2F17%2F17%2F014

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