Figure reveals that even incorporating polarization orthogonal to the plane of the nucleobases (as in Drude-2017 and AMOEBA) does not significantly improve the overall total interaction energy. This is a bit counterintuitive, as stacking is mostly driven by dispersion interactions that approximate an induced dipole-induced dipole forces in the non-overlapping regime. Nevertheless, all 3 polarizable models have nearly identical median and spread between ∆E frz and ∆E int . While E int s for Amber99 are also on par with the other force fields, the magnitudes of the three energies that make up E frz other than AmberFD tell a different story. Recall that frozen energies are computed as the sum of three terms,