  We investigate the dynamics of Na clusters embedded in Ar matrices. We use a
hierarchical approach, accounting microscopically for the cluster's degrees of
freedom and more coarsely for the matrix. The dynamical polarizability of the
Ar atoms and the strong Pauli-repulsion exerted by the Ar-electrons are taken
into account. We discuss the impact of the matrix on the cluster gross
properties and on its optical response. We then consider a realistic case of
irradiation by a moderately intense laser and discuss the impact of the matrix
on the hindrance of the explosion, as well as a possible pump probe scenario
for analyzing dynamical responses.
