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This article compares the experimental results obtained in metal-assisted secondary ion mass spectrometry of polymers, with molecular dynamics simulations involving hybrid metal-organic surfaces. The theoretical sputtering yields are in agreement with the trends highlighted in recent experiments, in which different projectiles (Ga + , C + 60 ) were used to bombard pristine and Au-covered polymer samples. In the experiments, the link between the organic ion yield enhancement/decrease and the fraction of the surface covered by the metal is clearly established. On the other hand, the simulations show that the position of the impact point on the metal-covered surface critically influences the calculated yields of metal and organic material, in a manner that depends on the projectile. The discussion analyzes the information obtained from the simulations and the experiments to propose a mechanism of yield enhancement.

The properties of materials, even at the atomic level, evolve on macroscopic time scales. Following this evolution through simulation has been a challenge for many years. For lattice-based activated di↵usion, kinetic Monte Carlo has turned out to be an almost perfect solution. Various accelerated molecular dynamical schemes, for their part, have allowed the study on long time scale of relatively simple systems. There is still a need, however, for methods able to handle complex materials such as alloys and disordered systems. Here, we review the kinetic Activation-Relaxation Technique (k-ART), one of a handful of o↵-lattice kinetic Monte Carlo methods, with on-the-fly cataloging, that have been proposed in the last few years.