The electron free flying time is determined by the electron -neutral particle collision frequency.

电子的自由飞行步长由电子与中性粒子的碰撞频率来决定。

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The energy of light varies across the spectrum (blue light is more energetic than red) but only a certain amount of energy is needed to knock an electron free.

光谱中光的能量是不同的(蓝光比红光更具能量)，但是只需一种确定的能量来碰触电子使其脱离。

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But we see if we have a free electron, as we do in this dotted line here, that's going to be a higher energy that's less stable.

但是我们看到如果，我们有一个自由电子，就像虚线所示那样，那将会是一个较高的，不够稳定的能量。

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This should make sense, because if an atom has a very high electron affinity, that means it's really happy taking an electron from another atom, or taking a free electron -- that that's very favorable.

这应该是合理的，因为如果一个原子有很高的电子亲和能，这意味着,它非常乐意从另外一个原子那里夺取一个电子，或者得到一个自由电子--这是非常利于发生的。

麻省理工公开课 - 化学原理课程节选

But we see if we have a free electron, as we do in this dotted line here, that's going to be a higher energy that's less stable.

但是我们看到如果,我们有一个自由电子，就像虚线所示那样，那将会是一个较高的,不够稳定的能量。

麻省理工公开课 - 化学原理课程节选

And so the energy is zero because the electron is no longer bound. It is free.

所以这个系统能量为0，因为,电子不再受束缚了，它自由了。

麻省理工公开课 - 固态化学导论课程节选

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