mirror of https://gitlab.com/QEF/q-e.git
26 lines
1009 B
Plaintext
26 lines
1009 B
Plaintext
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This example illustrates how to calculate electron-phonon interaction
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coefficients, for a (444) Monkhorst-Pack (MP) grid of q-points, in fcc Al
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by using the optimized tetrahedron method.
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IMPORTANT NOTICE: the calculation of electron-phonon coefficients is tricky.
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Do not attempt it unless you have a clear idea of the technical problems
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(e.g. very slow convergence with k-point grid,, divergence at q=>0 for optical
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modes). Carefully read the relevant literature first.
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The calculation proceeds as follows (for the meaning of the cited input
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variables see the appropriate INPUT_* file)
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1) make a self-consistent calculation for Al by using the optimized tetrahedron method
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(occupation = "tetrahedra_opt").
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2) make the phonon calculation for the shifted grid of q-points.
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ldisp = .true. and lshift_q = .true.
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3) make the electron-phonon calculation for the shifted grid of q-points.
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ldisp = .true. and lshift_q = .true. and electron_phonon = "lambda"
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4) Eliashberg function with alpha2f.x .
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