Reorientation of magnetic moments under mechanical stresses in FeCl 2 at 0 K : theoretical predictions

2014 We predict in the case of FeCl2 which is an uniaxial antiferromagnet for T ~ TN (~ 25 K), that one can modify the Fe+2 ions crystalline field symmetry by applying a mechanical stress and hence modify the moment orientation of these ions. We give as function of the crystalline field variation 03B4W, an expression for the components of the tensor which relates the moment variation of each ion with the crystal strains. 0 K results are obtained for the antiferromagnetic and saturated paramagnetic phases, this latter phase being obtained by application of a strong enough magnetic field along the moment alignment direction. Our results are compatible with symmetry considerations. The size of the predicted moment variation suggests that it could be observed experimentally. From the tensor components measurement one can deduce the value of some of the crystalline field derivatives with respect to strains. J. Physique 41 ( 1980) 627-632 JUILLET 1980, Classification Physics Abstracts 76.80 75.80 75.50E 75.30G