Unraveling the dynamics of coupled fluxes at the mineral-water interface by investigating space-time dependent response through molecular dynamics simulation

Understanding the microscopic interplay of mass, solute, heat, and charge transport at mineral-water interfaces is key to unraveling critical geophysical processes. In this work, we present a novel unified methodology that leverages a space- and time-dependent local response matrix to explore the intricate dynamics at the quartz-water interface. By applying molecular dynamics simulations and a generalized Green-Kubo formalism, we capture the properties of coupled fluxes within a deprotonated quartz nanochannel. Our approach enables us to surgically probe fundamental processes, including ion dynamics, water relaxation, and specific surface interactions, as well as how salt concentration, geometry, and surface charge modulate the coupling of fluxes via these mechanisms. The detailed space-time response framework bridges molecular behavior with hydrodynamic theories, enhancing our fundamental knowledge of nanoscale fluid transport. The insights gained from this work contribute to an improved understanding of mineral-fluid interfaces with implications for geophysics, electrochemistry, and various technological applications.