where Ψ ({r A }) and Ψ 0 ({r A }) are Gaussian ground-state wave functions of interacting and non-interacting oscillators, respectively. The explicit expression for ρ pol (r) can be found in the Supporting Information (Section II). The optimal choice of QDO charges q A is essential for accurate density predictions. Using the vdW-OQDO parametrization, we assign species-specific charges based on polarizabilities and C 6 coefficients, in contrast to ear-lier methods using arbitrary q A = 1 a.u. charge values . Figure shows the histogram of these charges for the S12L dataset.