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Hi all,</div>
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I've been looking some non-periodic systems lately, and as such have been using the Makov-Payne correction to both correct for the dipole moment of my molecules, but also because I occasionally am dealing with charged systems and need to correct for the
vacuum level shift. My main question as of right now is regarding the use of the Makov-Payne corrected energies while running relax calculations.</div>
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From the original Makov-Payne paper, when the lowest non-vanishing multipole is a quadrupole, the electrostatic potential is constant at all points in the unit cell, and therefore does not affect the forces on the ions and electrons in the cell.</div>
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However, in the case of the lowest non-vanishing multipole being a dipole, there should be a contribution from the dipole field on the forces. The Makov-Payne paper seems to imply that the convergence of the forces will be affected by the dipolar term, however
it also notes that the dipoles in a cubic lattice do not interact. I am unsure if this means that there is no influence of the dipole on the forces in a cubic lattice, or if there is an influence of the dipole forces on the ions, but that the dipoles do not
alter each other in a cubic lattice, i.e. there are no dipole-induced dipoles.</div>
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I know from running a few sample calculations that the Makov-Payne correction in Quantum ESPRESSO does not influence the forces, which I could tell by a comparison of the forces from a calculation with the correction and one without, all else being the same.</div>
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If it is the case that the dipole affects the ions, should the Makov-Payne correction not be applied in some manner to the forces, and if so, how can I try to test that?</div>
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Thanks, </div>
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<p style="direction: ltr; margin-top: 0px; margin-bottom: 0px;">Brock Dyer, Class of 2025</p>
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