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A Quantum Monte Carlo Approach to the Adiabatic Connection Method

Maziar Nekovee·W. M. C. Foulkes·A. J. Williamson·G. Rajagopal·R. J. Needs
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Abstract

We present a new method for realizing the adiabatic connection approach in density functional theory, which is based on combining accurate variational quantum Monte Carlo calculations with a constrained optimization of the ground state many-body wavefunction for different values of the Coulomb coupling constant. We use the method to study an electron gas in the presence of a cosine-wave potential. For this system we present results for the exchange-correlation hole and exchange-correlation energy density, and compare our findings with those from the local density approximation and generalized gradient approximation.

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Maziar Nekovee, W. M. C. Foulkes, A. J. Williamson, G. Rajagopal, R. J. Needs. 1998-06-05. A Quantum Monte Carlo Approach to the Adiabatic Connection Method. https://doi.org/10.1016/s0065-3276(08)60436-0

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