Within Phonopy, the NAC term is typically integrated into the calculation of the dynamical matrix by specifying the Born effective charges (Z * i,αβ ) and the electronic part of the static dielectric tensor (ϵ ∞ αβ ). However, the direct application of the NAC term in the HiPhive fitting can not fully address the long-range Coulomb interactions arising from the macroscopic electric field. It shows discernible oscillations in phonon modes at the Γ point, as illustrated in Figure when applying the NAC only.