Dissolution Characteristics at the Quartz-Water Interface in Different Environments: Insights from Molecular Dynamics Simulations

Mineral-water interfacial reactions exert profound impacts across multiple fields. In this study, we employed classical molecular dynamics (CMD) simulations to investigate the reaction characteristics at the quartz-water interface under varying conditions. Research has revealed that the quartz-water interface serves as a crucial material exchange channel during the reaction processes, and the interface is at the forefront of dissolution reactions. During the reaction, a portion of hydrogen atoms from the aqueous solution enters the crystal interior, while hydroxyl hydrogen atoms and oxygen atoms on the quartz surface migrate to both the solution and the crystal interior. Dissolved silicon atoms also migrate into the solution, with all of these processes occurring across the quartz-water reaction interface. Stress, pH value, and environmental pressure all exert a promoting effect on quartz dissolution, and the simulation results reveal clear material transfer processes at the interface. The quartz-water reaction interface exhibits a thickness of several angstroms. Notably, the Si-O bond length at the interface is slightly longer than that in the crystal interior, and dissolution products of quartzsuch as Q(1) and Q(0)are detectable at the interface. These findings provide new insights into the quartz-water interface at the molecular/atomic scale.