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arXiv · 2206.03228

Perturbation Calculation of the Uniform Electron Gas with a Transcorrelated Hamiltonian

Hongjun Luo·Ali Alavi
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Abstract

With a transcorrelated Hamiltonian, we perform a many body perturbation (MBPT) calculation on the uniform electron gas in the high density regime. By using a correlation factor optimised for a single determinant Jastrow ansatz, the second order correlation energy is calculated as $\frac{1-\ln2}{\pi^{2}}\ln(r_{s})-0.05075$. This already reproduces the exact logarithmic term of the random phase approximation (RPA) result, while the constant term is roughly $7\%$ larger than the RPA one. The close agreement with the RPA method demonstrates that the transcorrelated method offers a viable and potentially efficient method for treating metallic systems.

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Hongjun Luo, Ali Alavi. 2022-06-07. Perturbation Calculation of the Uniform Electron Gas with a Transcorrelated Hamiltonian. https://doi.org/10.1063/5.0101776

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