On the other hand, the machine learning model shows excellent agreement with the reference quantum calculations for all three test cases. The model correctly predicts that molecules in shells closer to the ions have larger dipole moments and thus are more strongly polarized. Further, the polarization effect is larger around Mg 2+ compared to Cl -because the ion is twice as charged. Note that the model tends to slightly underestimate the dipole moment. This underestimation relates to the test clusters ( June 27, 2023 7/19 molecules) being larger than the water clusters the model was trained on (15 molecules). It has been shown that polarization effects increase with water cluster size, approaching bulk water behavior in clusters with more than 26 water molecules . In addition, waters near the centers of clusters have been shown to be more strongly polarized compared to waters on the edges of clusters due to their greater numbers of hydrogen bonds . Based on the water only data (Fig. ), the machine learning model captures this behavior and also matches with quantum reference calculations, as waters near the center of the cluster (water shell 1) have dipole moments close to bulk water (2.9 D) whereas waters on the edges of the cluster (water shell 3) have dipole moments approaching monomeric water (1.85 D) .