 The next thing to appreciate about this structure is that it will have a puckered hexagonal ring as is characteristic of the wordsite structure, and the arrangement of hydrogens within that ring is partially random. They pack in a staggered herringbone fashion that looks like this. So one of these molecules edge on looks like this line. The next one is rotated with respect to the first, etc. And they're going to do this so that we can maximize the density of the material. So let's just imagine how one iron atom might influence the alignment of the spins on the next iron atom. So I will start and I will choose arbitrarily that that atom has a net spin of four bore magnetons in the up direction. The key point to recognize is that the oxygen iron bond is largely ionic, but there is some degree of covalency. And because there's some degree of covalency, the electron in this oxygen 2px orbital will spend some time shared interacting with the electrons in the d orbital.