Understanding frictional phenomena is a fascinating fundamental problem with
huge potential impact on energy saving. Such an understanding requires
monitoring what happens at the sliding buried interface, which is almost
inaccessible by experiments. Simulations represent powerful tools in this
context, yet a methodological step forward is needed to fully capture the
multiscale nature of the frictional phenomena. Here, we present a multiscale
approach based on linked ab initio and Green's function molecular dynamics,
which is above the state-of-the-art techniques used in computational tribology
as it allows for a realistic description of both the interfacial chemistry and
energy dissipation due to bulk phonons in non-equilibrium conditions. By
considering a technologically relevant system composed of two diamond surfaces
with different degrees of passivation, we show that the presented method can be
used not only for monitoring in real-time tribolochemical phenomena such as the
tribologically-induced surface graphitization and passivation effects but also
for estimating realistic friction coefficients. This opens the way to in silico
experiments of tribology to test materials to reduce friction prior to that in
real labs