MEASUREMENT OF THE COVALENT SPIN DISTRIBUTION IN MANGANOUS FLUORIDE USING POLARIZED NEUTRONS

The spatial distribution of the covalent spin density in MnF2 has been obtained from a measurement of the ``forbidden'' magnetic scattering in the nuclear reflections using polarized neutrons. A partial Fourier map of the projected covalent spin on the basal plane was prepared. A model representing the covalent spin by isolated spherical charges that is consistent with the experimental data indicates that the covalent spin density for a single bond undergoes a change in sign as we proceed from the Mn2+ to the F− ion. That part closest to the 3d unpaired electrons carries the same sign as the magnetic ion. The results are discussed in terms of the existing theory.