So if we think about, for example, this red line here, which energy state or which principle quantum number do you think that our electron started in?

我们来看看，比如这里的这个红线，它是从主量子数,等于多少的能级发出的？

麻省理工公开课 - 化学原理课程节选

So these names, they don't really make any sense why they're called past s p and f, and it turns out that it comes from spectroscopy terms that are pre-quantum mechanics where, for example, this is called the sharp line, I think the principle, the diffuse, and the fundamental.

看到这些名字，你会发现,它们为什么叫s，p，f是没什么道理的，事实上,它们来源于,量子力学之前的光谱学中的术语，例如，它们分别叫做锐线，我认为是主线，漫射和基本。

麻省理工公开课 - 化学原理课程节选