Molecular scale mechanism of thermal resistance at solid-liquid interfaces (influence of interaction parameters between solid and liquid molecules)

Nonequilibrium molecular dynamics simulations have been performed for systems of a liquid film confined between atomistic solid walls. The two solid walls have different temperatures to generate a steady thermal energy flux in the system, which is the element of macroscopic heat conduction flux. Three kinds of liquid molecules and three kinds of solid walls are examined, and the thermal energy flux is measured at control surfaces in the liquid film and at the solid-liquid interfaces. By analyzing the thermal energy flux in detail by decomposing it into several molecular-scale contributions, influence of interaction parameters between solid and liquid molecules and the spacing of molecular alignment on the surface of the solid wall are clarified, and the molecular-scale mechanisms that govern the thermal resistance at a solid-liquid interface are elucidated.