  The potential energy surface (PES) of Lennard-Jones clusters is investigated
using the activation-relaxation technique (ART). This method defines events in
the configurational energy landscape as a two-step process: (a) a configuration
is first activated from a local minimum to a nearby saddle-point and (b) is
then relaxed to a new minimum. Although ART has been applied with success to a
wide range of materials such as a-Si, a-SiO2 and binary Lennard-Jones glasses,
questions remain regarding the biases of the technique. We address some of
these questions in a detailed study of ART-generated events in Lennard-Jones
(LJ) clusters, a system for which much is already known. In particular, we
study the distribution of saddle-points, the pathways between configurations,
and the reversibility of paths. We find that ART can identify all trajectories
with a first-order saddle point leaving a given minimum, is fully reversible,
and samples events following the Boltzmann weight at the saddle point.
