And, likewise, we get over to here and finally, look, here is 5d and 5f almost at the same level.

照这样，我们分析到最后，看，5d和5f层几乎是在同一层。

麻省理工公开课 - 固态化学导论课程节选

And this is an example where unoccupied 5d lies below 4f.

这就说明,未布满的5d层在4f层下面。

麻省理工公开课 - 固态化学导论课程节选