system it has to be roughly 20 a.u. However, we do not observe any adverse effects by using shorter cutoffs, except for GB1, which could be related to the use of an atom-based partitioning scheme for that particular system. Ideally, the long-range coupling should reproduce the short-range coupling but at a reduced computational cost. To achieve this, it is a sufficient requirement that the errors are equal to or lower than the numerical precision of the calculated properties which is determined by the SCF convergence threshold used in the single-point calculations. From Figure it can be seen that the total energy converges only for the small solute-solvent system. However, for these systems it converges at a cutoff distance where only very few solvent molecules are treated using the long-range coupling. The savings in computational cost are therefore negligible compared to using the short-range coupling for the entire system. The situation is different for the other properties as can be seen in Figures and. The numerical precision of these properties is roughly of the order of 10 -6 a.u. This point is first reached at cutoff distances of roughly ∼ 24 a.u. for the solute-solvent systems while the GB1 system requires a much longer cutoff distance of ∼ 40 a.u. to fully converge. In the latter case, we used a partitioning based on interatomic distance that does not ensure that the total charge of the short-and long-range parts is neutral. This may partly account for the longer cutoff distances needed for GB1.