The crystal and magnetic structures of the lanthanum cobaltites La0.6S
r0.4CoO3, La0.6Sr0.4Co0.9Fe0.1O3 and La0.6Ba0.4Co0.9Fe0.1O3 have been
studied by neutron powder diffraction at temperatures of 2, 300 and 90
0 K. All compounds undergo a phase transition from cubic to rhombohedr
al structure. Below the room temperature La0.6Sr0.4CoO3 becomes ferrom
agnetic while for the components with 10% Fe substituted for Co, we fo
und an antiferromagnetic older. (C) 1998 Elsevier Science B.V. All rig
hts reserved.