In both cases, the box is partitioned into three regions: (i) the FG region, which contains the solute surrounded by unscaled solvent molecules; (ii) the SG region, where the scaling factor is progressively increased from 1 to s max ; and (iii) the CG region, where the solvent is homogeneously scaled at s max . The widths of these regions are denoted d FG , d SG , and d CG , respectively.