"Everyone is half-dead. It does not matter if you shell them because you are shelling a dead body."

VOA: standard.2010.01.02

So the 3 s 1, or any of the other electrons that are in the outer-most shell, those are what we call our valence electrons, and those are where all the excitement happens.

它们是经常发生激发情况的,那也是我们所看到，我们称之为价电子，它们是经常发生激发情况的。

麻省理工公开课 - 化学原理课程节选

So let's do a quick clicker question, and you tell me how many valence electrons does fluorine have? Remember, valence electrons are different from core, they're only the outer-most electrons in the outer-most shell.

那么让我们来做一个小选择题，请大家来告诉我,氟有多少个价电子，要记得，价电子与芯电子不同，它们是在最外壳层的最靠外面的电子。

麻省理工公开课 - 化学原理课程节选

So when we talk about p orbitals, it's similar to talking about s orbitals, and the difference lies, and now we have a different value for l, so l equals 1 for a p orbital, and we know if we have l equal 1, we can have three different total orbitals that have sub-shell of l equalling 1.

当我们考虑ｐ轨道时，这和ｓ轨道的情形和相似，不同之处在于ｌ的值不一样，对于ｐ轨道，ｌ等于１,我们知道如果ｌ等于１,我们有３个,不同的轨道。

麻省理工公开课 - 化学原理课程节选

So basically, that means one electron in an s orbital in their outer-most most shell.

因此基本上,这意味着那个在，s，轨道上价电子是最外层的。

麻省理工公开课 - 化学原理课程节选

Core electrons are all those electrons held in really tight with the nucleus in the inner shells, whereas the valence electrons are only those electrons that are in the outer-most shell, or at your highest value of n of the principal quantum number.

芯电子是那些,在内壳层被原子核束缚得非常紧的电子，而价电子只包括,最外层的电子，或者说主量子数，n，的值最大的那些电子。

麻省理工公开课 - 化学原理课程节选

And the reason is simply because the energy that Z we gain in terms of moving up in z, 5 so from going to z equals 4 to z equals 5, -- is actually outweighed by the energy it takes to go into this new shell, to go into this new sub shell.

原因很简单,就是因为我们通过提升，所得到的能量--从，Z，等于，4，到，Z，等于，事实上比填充到这个新的壳层,新的亚壳层，所消耗的能量更多。

麻省理工公开课 - 化学原理课程节选

The other main difference that we're really going to get to today is that in multi-electron atoms, orbital energies depend not just on the shell, which is what we saw before, not just on the value of n, but also on the angular momentum quantum l number. So they also depend on the sub-shell or l.

我们今天要讨论的,另一个很重要的区别就是,在多电子原子中，轨道能力不仅仅依赖于，我们以前看到的外层，不仅仅依赖于n的值，而是与角动量量子数也有关系,所以它们也依赖于亚外层或者。

麻省理工公开课 - 化学原理课程节选

So what I want to point out when you're kind of looking at these numbers here, what the significance is, look at that huge difference between what the ionization energies are for what we call those valence electrons, -- those outer shell electrons, those are core electrons there.

我在这里想要指出的是,当大家在看这些数字的时候，最重要的是，要看到这些,巨大的差异,看到所谓价电子，即外层电子的电离能与，1，s，轨道，电离能之间的巨大差异。

麻省理工公开课 - 化学原理课程节选