So we're going to feel a higher z effective in the case of the ion compared to the neutral atom.

因此，我们在离子中,会比在中性原子中感受到更高的有效核电量。

麻省理工公开课 - 化学原理课程节选

So what we're going to see is less shielding, which means that it will actually feel a higher z effective.

那么我们将会看到更少的屏蔽，这意味着将会感受到更大的有效核电量。

麻省理工公开课 - 化学原理课程节选

In 1931, at Columbia University, Harold Yuri discovered this isotope, which has two.

931年在哥伦比亚大学，哈罗德尤里发现同位素，有两个核电荷数。

麻省理工公开课 - 固态化学导论课程节选

If we have a higher z effective, it's pulled in tighter, we have to put in more energy in order to eject an electron, so it turns out that that's why case 2 is actually the lowest energy that we need to put in.

而如果有效核电量更高，原子核的束缚也就更紧，我们不得不输入更多的能量来打出一个电子，这就是第二种情况,所需要输入的,能量更少的原因。

麻省理工公开课 - 化学原理课程节选

The first is this the z effective, or how much charge is actually in the nucleus that's felt, Z or the I guess we would say the z, how much the charge is on the nucleus that holds it close together.

第一个是有效核电量，或者说实际感受到的核电荷量，又或者我想我可以说就是，使它们保持在一起的,原子核的电荷量。

麻省理工公开课 - 化学原理课程节选

Not only are we taking away an electron here, but we're also going to decrease shielding, so the electrons that are already in there are going to feel a higher z effective and will be pulling and the atom will be getting smaller.

这不只是因为我们拿走了一个电子，还因为我们这样做会减小屏蔽效应，这样留下的电子,将会感受到更大的有效核电量,也就会感受到更强的吸引力，使得原子变得更小。

麻省理工公开课 - 化学原理课程节选

You just need to remember what's happening to z effective, which really tells us what's happening with all the trends, and once you know z effective, you can figure out, for example, what direction the atomic radius should be going into.

你只需要记住有效核电量的规律，实际上它会告诉我们所有的规律，只要你知道了有效核电量的规律，你就可以判断，比如，原子半径会向着哪个方向发展。

麻省理工公开课 - 化学原理课程节选

The z effective is lower, so we have to put less energy in to get an ion out.

它的有效核电量更低，所以我们只需要更少的能量就能打出一个离子。

麻省理工公开课 - 化学原理课程节选

And we know as we go across a row in the periodic table, what's happening is that z effective or the effective pull on the nucleus is increasing.

而我们知道沿着周期表的某一行向右看，有效核电量,或者说原子核的有效引力是在逐渐增大的。

麻省理工公开课 - 化学原理课程节选

So it looks like not too many more than half of you got this correct, so make sure you can look at your periodic table and figure out how to think about ionization energy in terms of z effective, not just in terms of memorizing what that trend is.

看起来只有一半多一点的人,做对了，所以请大家务必做到能够通过观察周期表,并在考虑电离能时,从有效核电量的观点出发，而不是仅仅依靠记住这个规律。

麻省理工公开课 - 化学原理课程节选

This is because even though z, the atomic number is still increasing, we are also getting further away from the nucleus.

从有效核电量方面来想一想为什么，这是因为，尽管，Z，原子序数依然在变大，但我们同时也在离原子核越来越远。

麻省理工公开课 - 化学原理课程节选

The reason it's aluminum is because aluminum has a lower z effective, so it's not being pulled in as tightly by the nucleus, and if it's not being pulled in as tightly, you're going to have to put in less energy in order to ionize it, so that's why it's actually going to have the smaller ionization energy.

原因是,铝的有效核电量更少，所以没有被原子核束缚得更紧，而如果没有被束缚得更紧，你为了电离它所需要注入的能量也就更少，这就是,它的电离能会更低的原因。

麻省理工公开课 - 化学原理课程节选