ORBITAL MAGNETISM IN FEO

Using the rotationally invariant LDA + U approach we investigate the e ffect of the rhombohedral distortion on the orbital magnetism of FeO. The latter plays a very important role both for stretching and compres sive deformations. In the first case. a large orbital magnetic moment is stabilized along the [1 1 1] direction of the cube and causes simil ar reorientation for the spin counterpart. Opposite distortion (compre ssion) turns the magnetic moments to the plane (1 1 1) where the orbit al component is least quenched. (C) 1998 Elsevicr Science B.V. All rig hts reserved.