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arXiv · 1707.01995

Ground state properties of 3d metals from self-consistent GW approach

Abstract

Self consistent GW approach (scGW) has been applied to calculate the ground state properties (equilibrium Wigner-Seitz radius $S_{WZ}$ and bulk modulus $B$) of 3d transition metals Sc, Ti, V, Fe, Co, Ni, and Cu. The approach systematically underestimates $S_{WZ}$ with average relative deviation from the experimental data about 1% and it overestimates the calculated bulk modulus with relative error about 25%. It is shown that scGW is superior in accuracy as compared to the local density approximation (LDA) but it is less accurate than the generalized gradient approach (GGA) for the materials studied. If compared to the random phase approximation (RPA), scGW is slightly less accurate, but its error for the 3d metals looks more systematic. The systematic nature of the deviation from the experimental data suggests that the next order of the perturbation theory should allow one to reduce the error.

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BibTeXRIS

Andrey L. Kutepov. 2017-07-06. Ground state properties of 3d metals from self-consistent GW approach. https://doi.org/10.1088/1361-648x%2Faa91b6

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