Atomistic Modeling of Friction

Theoretical Approaches for Understanding the Interplay Between Stress and Chemical Reactivity

“…In order to simulate chemical reactions, i.e., processes involving changes in bonding, it is generally necessary to employ a potential derived from quantum chemical (QC) methods or reactive force fields. These techniques have been used extensively in the context of simulating tribochemical reactions [48,49]. For instance, Harrison et al performed a series of studies modeling hydrogen-passivated diamond interfaces using constant strain simulations.…”

“…The use of static simulation methods to study the changes in energy and structure that occur during tribochemical processes has a long history [48,49]. These methods have been used to optimize the reactants and products of tribochemical reactions, to examine the PES associated with the movement of surfaces relative to one another, and to identify the MEPs connecting the reactants and products of tribochemical reactions.…”

“…The release of this energy can lead to large increases in the temperature of the system, which accumulate if not dissipated. Dissipation can be achieved through the use of thermostats; however, the thermostat needs to be applied carefully to ensure the energy is removed from the system in a manner that is consistent with the non-equilibrium nature of these simulations [49].…”

“…However, the stress-induced processes involving bulk systems have been modeled extensively in the context of tribology, which is the study of friction, wear, and lubrication [48,49]. As such, potential exists to apply existing techniques used to study systems such as sliding contacts in the context of the mechanochemical activation of reactions occurring in bulk systems where shear and compressive stresses play key roles in activating reactions.…”

Structure and nanotribology of thermally deposited gold nanoparticles on graphite

“…Thanks to the single-asperity nature of the contact formed between the AFM tip and the sample surface, various nanotribology experiments conducted on a large number of sample surfaces over the last couple of decades have resulted in the precise determination of the effect of normal load, sliding velocity and temperature on frictional behavior at the nanoscale [6][7][8]. Moreover, phenomena such as stick-slip [9] and superlubricity [10] have been observed and largely explained, in many cases with substantial support from theory and computational work [11].…”