  We study silicene on hexagonal boron nitride, using first principles
calculations. Since hexagonal boron nitride is semiconducting, the interaction
with silicene is weaker than for metallic substrates. It therefore is possible
to open a 50 meV band gap in the silicene. We further address the effect of Mn
decoration by determining the onsite Hubbard interaction parameter, which turns
out to differ significantly for decoration at the top and hollow sites. The
induced magnetism in the system is analyzed in detail.
