We
perform trajectory-based simulations of the vibrational predissociation
of the ArBr2(B,ν=16···25) van der
Waals triatomic complex, constrained to the T-shape geometry. To this
aim, we employ a 2-fold mapping of the quantum dynamics into classical-like
dynamics in an extended phase space. The effective phase space comprises
two distinct sets of degrees of freedom, namely a collection of coupled
harmonic oscillators and an ensemble of quantum trajectories. The
time evolution of these variables represent bound and unbound motions
of the quantum system, respectively. Quantum trajectories are propagated
within the interacting trajectory representation. The comparison between
the lifetimes of the predissociating complexes computed using the
trajectory-based approach and the experimental results available for
the target systems indicates that the present method is competitive
with wavepacket propagation techniques. The competition between several
simultaneous vibrational relaxation pathways was found to have a direct
impact on the time scales of vibrational predissociation. Likewise,
the analysis of the time evolution of the trajectories reveals the
existence of regions in the effective phase space where transitions
to vibrational states of higher energy are more likely to occur. The
size and location of these regions influence the transient vibrational
distributions and therefore the computed lifetimes. Furthermore, the
mechanisms of energy redistribution along the dissociation coordinate
are analyzed.