Finally, explicit solvation involves a gas phase computation of a solute, often with the addition of up to four solvent molecules surrounding the solute. This practice is commonly used in modeling ionic species due to their increased interactions with the solute. The solvation shell, an area around the solute where the solute molecule's presence disrupts the solvent's bulk structure, will generally increase as the polarity of the solute increases. Thus, when modeling ionic species, an implicit solvation model may fail to adequately describe the solvation shell, which alters many of the characteristics of the solute, including dipole. Additionally, information regarding the solute-solvent interactions can be gained through explicit solvation, as well as a better understanding of how solvent location affects the nature of the solute. A primary drawback to explicit solvation is its high computational cost. Additionally, there is the question of chemical stability, specifically when using a low number of solute molecules.