Magnetic phase transitions of MnWO4 studied by the use of neutron diffraction.

Neutron-powder-diffraction data, collected with the D1B diffractometer, and single-crystal data, collected with the D10 four-circle diffractometer, both at the Institut Max von Laue-Paul Langevin, Grenoble, and single-crystal data, collected with the DN4 four-circle diffractometer at the Centre d'Etudes Nucleaires de Grenoble, show that MnWO 4 (space group P2/c) undergoes three magnetic phase transitions below 14 K. The transition temperatures are 13.5 K (paramagnet-AF3), 12.3 K (AF3-AF2), and 8.0 K (AF2-AF1). Phases AF3 and AF2 are incommensurate with the crystallographic lattice