where S represents the score and EM D g OO , EM D g OH , and EM D g HH represent the Earth mover's distance measurements of the three RDFs considered, namely the Oxygen-Oxygen, Oxygen-Hydrogen, and Hydrogen-Hydrogen, respectively. In this way, the scoring function does not capture discrepancies only in terms of distances and spatial displacement of the water molecules respect to each other, but also in terms of their natural orientation. This provides us with a scoring function which is rich in microscopic structural information on the system.