NEUTRON LAUE DIFFRACTION FROM THE MAGNETIC-STRUCTURE OF 4-PERCENT GA-DOPED FEGE2

Laue neutron-diffraction patterns from a single crystal of 4% Ga-doped FeGe2 at temperatures between 306 and 87 K have been recorded on neut ron-sensitive image plates. The diffraction diagrams confirm that ther e is a paramagnetic to spiral antiferromagnetic structural change with a propagation vector 1 + delta 0 0 with delta similar to 0.11 at simi lar to 290 K, and a further change at similar to 180 K to a 'locked-in ' non-harmonic spiral phase with delta equal to exactly 1/10. (C) 1998 Elsevier Science B.V. All rights reserved.