As soon as lanthanum takes that electron, this level rises ever so slightly, and then we jump down here and fill in the lanthanide.

一旦镧得到了电子，这一层就会稍稍上升，然后我们向下填一下镧系元素。

麻省理工公开课 - 固态化学导论课程节选

They're not going to want to add on another electron, because then it'll have to jump a very large energy level go from n equals 2, to n equals 3, and n equals 4, and so on.

它们不愿意增加另外一个电子，因为这会让它们跳到一个非常高的能级上去,依次是，n，等于，2，3，4，等等。

麻省理工公开课 - 化学原理课程节选