One of the defining properties of dark matter is that it interacts only weakly at most, or else we would see an entirely different distribution. Ordinary matter

One of the defining properties of dark matter is that it interacts only weakly at most, or else we would see an entirely different distribution. Ordinary matter can dissipate heat because of electromagnetic interaction and thus collapse into galaxies. Dark matter can't, so it only forms diffuse, homogeneous halos. The idea of "dark chemistry", whole not whacky enough to be immediately discarded, is highly exotic. https://www.space.com/21508-dark-matter-atoms-disks.html https://www.space.com/21508-dark-matter-atoms-disks.html