And as you go to higher and higher levels, those energy levels, as you saw in the case of hydrogen, are more closely spaced.

当能级变得越来越高，那些高能级的轨道，就会变得越来越接近，正像你在氢原子里看到的那样。

麻省理工公开课 - 固态化学导论课程节选

And so when they become very, very closely spaced there is mutual repulsion of those electrons.

所以当它们越来越近的时候,这些电子会产生相互的排斥力。

麻省理工公开课 - 固态化学导论课程节选