  The results of the electronic structure calculations performed on SmN by
using the LDA+U method with and without including the spin-orbit coupling are
presented. Within the LDA+U approach, a N(2$p$) band polarization of $\simeq
0.3\ \mu_B$ is induced by Sm(4$f$)-N(2$p$) hybridization, and a half-metallic
ground state is obtained. By including spin-orbit coupling the magnetic
structure was shown to be antiferromagnetic of type II, with Sm spin and
orbital moments nearly cancelling. This results into a semiconducting ground
state, which is in agreement with experimental results.
