Crystal symmetry of the low temperature phase of magnetite

A neutron diffraction study of magnetite below the Verwey transition (123 K) reveals that the superlattice reflections are observed for (hhl), with l = integers $\text{+1}\text{2}$ but not for (hhl). This determines a (110) glide plane in the direction of [100] and implies that only one of the doubly degenerate modes, proposed recently by Yamada, condenses at the transition.