https://www.livescience.com/64729-new-uranium-singlet-magnet.html
"Under normal circumstances, the magnetic moments in a bar of iron become aligned gradually, without sharp transitions between magnetized and unmagnetized states. In a singlet-based magnet, the jump between states is sharper. Spin excitons, usually temporary objects, become stable when they cluster together. And when those clusters form, they start a cascade. Like dominoes falling into place, spin excitons fill the entire substance very quickly and suddenly, and align with one another.
That's what seems to be happening in USb2."
