  We present a theoretical study of the wave packet dynamics of the H$_2^+$
molecular ion in plasmon-enhanced laser fields. Such fields may be produced,
for instance, when metallic nano-structures are illuminated by a laser pulse of
moderated intensity. Their main property is that they vary in space on
nanometer scales. We demonstrate that the spatial inhomogeneous character of
these plasmonic fields leads to an enhancement of electron localization, an
instrumental phenomenon that controls molecular fragmentation. We suggest that
the charge-imbalance induced by the surface-plasmon resonance near the metallic
nano-structures is the origin of the increase in the electron localization.
