Using a finite-range density functional, we have investigated the ener
getics and structural features of mixed helium clusters. The possibili
ty of doping the cluster with a molecule of sulfur hexafluoride is als
o considered. It is seen that the repulsion introduced by the impurity
strongly modifies the properties of the smallest drops. Although only
a qualitative comparison is possible, the gross features displayed by
our calculations are in agreement with recent experimental findings.