Atoms orientation

[pbutkiewicz5]

FeI atoms lie at the corners of the cube, so they have three axes 4 fold axis lying along the edges of the unit cell and one 3 fold axis on the diagonal of the cube, this means that Vzz for this nucleus will be 0.
In the case of FeII, iron atoms, let’s consider an atom selected lying on the wall of the unit cell, we can recognize the axis of symmetry lying perpendicular to the wall, this is the 4-fold axis, and two axes of symmetry 2-fold ais lying parallel to the edge of the wall on which the atom is located (if it weren’t for the N atom in the middle, we would have a similar situation, in terms of local symmetries, as for FeI). So PAS is oriented perpendicular to the wall (Vzz _|_ to the wall for each of the 4 FeII atoms) and eta is equal to 0.

[Author]

Posts