  The rare-earth nitrides form a series of structurally simple $intrinsic$
ferromagnetic semiconductors, a rare class of both fundamental interest and
application potential. Within the series there is a wide range of magnetic
properties relating to the spin/orbit contributions to the ferromagnetic ground
states. We report an x-ray magnetic circular dichroism investigation of the
spin/orbit magnetic dipole alignments of Sm and Gd ions in epitaxial
Gd$_x$Sm$_{1-x}$N films. The Sm spin-alignment expectation value $\langle S_{z}
\rangle$ is seen to be strengthened by the Gd/Sm exchange interaction,
providing guidance concerning the composition for an angular momentum
compensation point (where the volume-averaged total angular momentum of a film
is zero).
