When a light particle,or photon, hits an electron, the electron jumps to a higher energy state.

VOA: special.2010.09.01

Now, if this incident energy is great enough it will take an electron out of the ground state and promote it.

现在，如果入射能足够的话,它会将一个电子从基态中释放出来,并且加速它。

麻省理工公开课 - 固态化学导论课程节选

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

What is the binding energy of the ground state electron in hydrogen?

氢在基态的情况下,它的电子结合能是多少？

麻省理工公开课 - 固态化学导论课程节选

This intuitively should make a lot of sense, because we know we're trying to minimize electron repulsions to keep things in as low an energy state as possible, so it makes sense that we would put one electron in each orbital first before we double up in any orbital.

这个直观上讲得通，因为我们知道尝试去最小化电子排斥力,从而尽可能的保持处于一个较低的能态,所以它讲得通,在我们在同一个轨道放入两个电子之前,我们首先把电子放入每一个轨道。

麻省理工公开课 - 化学原理课程节选

So, if, for example, we were looking at a hydrogen atom in the case where we have the n equals 1 state, so the electron is in that ground state, the ionization energy, it makes sense, is going to be the difference between the ground state and the energy it takes to be a free electron.

电离氢原子所需要的能量,如果我们看n等于1的情况,电子在基态，那电离能，很合理的就是基态,和自由电子态的能量差。

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