- the state has no orbital angular momentum,
- the state is somehow "planar"
It agrees with Gryzinski's model of hydrogen (~1965):
- zero angular momentum electron starts free falling toward nucleus,
- Lorentz force (magnetic dipole of electron - electric charge of nucleus) bends trajectory perpendicular to direction of spin,
- finally electron returns to the original distance, but on a different angle - analytic calculations give exactly 120 deg (independent to coefficients, slide 18 here: https://dl.dropboxusercontent.com/u/12405967/freefall.pdf ) - electron travels between vertices of equilateral triangle (r_max ~ 10^-10m, r_min ~ 10^-13m) in plane perpendicular to spin:
This is example of zero angular momentum object which still can rotate - it is allowed for complex systems, like for falling cat: https://en.wikipedia.org/wiki/Falling_cat_problem