  Recently it has been suggested that the role of electron-phonon coupling in
the mechanism of iron-based superconductors may have been underestimated and
that the antiferromagnetism and the induced xy potential may even have a
dramatic amplification effect on electron-phonon coupling. To substantiate the
recently announced xy potential in the literature, we create a two-channel
model to separately superimpose the dynamics of the electron in the upper and
lower tetrahedral plane. The results of our two-channel model support the
literature data. While the scientists are still searching for a universal DFT
functional that can describe the pairing mechanism of all iron-based
superconductors, we are designing an empirical combination of DFT functional to
calculate the electron-phonon coupling and antiferromagetism of LiFeAs, NaFeAs
and FeSe. We use ARPES data to revise the electron-phonon scattering matrix in
superconducting state to ensure that all electrons involved in iron-based
superconductivity are included in the ab-inito calculation. We present an
ab-initio theoretical approach that takes into account this amplifying effect
of antiferromagnetism and the correction of the electron-phonon scattering
matrix together with the abnormal soft out-of-plane lattice vibration of the
layered structure, which allows us to calculate theoretical Tc values of
LiFeAs, NaFeAs and FeSe as a function of pressure that correspond reasonably
well to the experimental values.
