"Triple-q→" Modulated Magnetic Structure and Critical Behavior of Neodymium

We have determined the magnetic structure of neodymium metal by combining the results of neutron diffraction studies on single crystals of neodymium with the results of Landau symmetry arguments and renormalization-group theory. The spins form a unique, two-dimensional, incommensurably modulated structure accompanied by a similarly modulated lattice distortion. The experimental value of the critical exponent $\beta =0.36\mathrm{}\pm 0.02$ is in agreement with the theoretical prediction of $\beta \sim 0.38$.