These are the first few complex spherical harmonics, which define the angular dependence of the Hydrogen atom’s quantum wavefunction. This wavefunction says essentially where it’s likely to find an electron hanging out around a hydrogen atom. So for example, if you lined up a lot (like, a lot a lot) of Hydrogen atoms in a row, measured the location of the electron for each, and plotted the positions, it would reproduce a cloud of points that looks a little bit like these shapes.
Anyway, doesn’t get (too much) tinier than the “electron cloud” of an atom.
This was all done in Sverchok, which I honestly don’t know how anyone lives without. I’m no good at geometry nodes. One day, though.