  It was claimed (Lloyd et al., PRL 108 (2012) 074802) that energy loss
magnetic chiral dichroism (EMCD) with electron vortex beams is feasible, and
has even advantages over the standard setup with Bragg diffracted waves. In
this Comment, we show that Lloyd et al. ignored an important constraint on the
proposed selection rule for the transfer of angular momentum in the
interaction, namely that it is only valid for an atom located in the very
center of the vortex. As an experimental consequence, the EMCD signal will only
be strong for extremely small nanoparticles of 1 to 2 nm diameter.
