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"The book is Darwin's Universe: Evolution from A to Z, and it is a life's work,"
VOA: standard.2009.11.25
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You need to know how to think about them in the same way we think about s and p orbitals, but for example, you don't yet need to know what all of the names are except for this 3 d z squared here.
你们只要知道，如何像考虑s和p轨道一样,来考虑它们，但你们不需要,知道它们的名字,除了这个3dz2轨道外。
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What you need to know is that when m equals 0, 3dz2 it's 3 d z squared.
你们要知道的是,当m等于0时，它是。
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X Y Z It's more interestingly named an X or Y or Z.
你也可以把它命名为。
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All right, it's so if I looked at it, sorry, IF x is less than y, THEN check to see IF x is less than z, and if that's true, print out x is the smallest.
好，代码是这样的，对不起，是不是x比y小，然后去看看是不是x比z小，如果都为真的话，显示x为最小值。
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Barthes, while writing this--he's writing what has perhaps in retrospect seemed to be his most important book, it's called S/Z.
巴特在创作这篇文章的时候,根据他的回忆这应该是他最重要的一本书，名叫《S\Z》
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Let's make this Z equals one.
然后我们让Z等于。
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So this is still a sigma it's a sigma 2 p z star orbital.
这还是一个sigma轨道,它是sigma2pz星轨道。
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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。
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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。
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And the nodal plane's going to be in the x z plane, or again, anywhere where phi is going to be equal to 0, that takes us to the x z plane.
节面是ｘｚ平面，又或者说是phi等于０的地方，这就是ｘｚ面。
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Let's bind z eh let's bind z to the-- f if I could type it would help-- say, f of 3. OK?
让我们给z赋值--如果我能打字就好了-,比方说？
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It looks a little something like that, and the screen doesn't quite do it justice here, Z but there's two alphabets; A through Z, and then A through Z, -- but the inner A through Z is on a small -- it has a smaller diameter; so it's a ring of letters.
它看起就像那样的东西，那个画面做的不是这么公正，这里有两个字母表，A到Z，然后A到，但是戒指内部的A到Z是在一个小直径的上面-,它有一个小的直径，所以它是一个有字母的戒指。
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So, if we think about this z bonding axis between the two carbon atoms, we can picture overlap of those s p hybrid orbitals, and then we can also picture bonding to hydrogen.
如果我们考虑,两个碳原子之间的z成键轴，我们可以画出sp杂化轨道的交叠，我们也可以画出和氢原子的成键。
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What is this orbital? Yup. And there's only 2pz one correct answer here, which is to 2 p z.
它的轨道是什么？，嗯，这里,只有一个答案，那就是。
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And just as with variables, you should use some common sense, some style here, and the function's name should X Y communicate what it does, calling it X or Y or Z is generally not all that helpful.
就像变量，你使用一些常识，一些类型，和函数名需要,传达它所做的事情，把它叫做,或者Z通常是没有什么用处的。
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So the value is z is 4, it's what I expect, right?
所以z的值等于？
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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。
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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。
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So here we have that graphed here, Z we have atomic number z graphed against ionization energy, so, let's fill in what the actual atoms are here, and we can see in general, yes, we're following the trend.
这就是我们要画的，横坐标是原子序数，纵坐标是电离能，让我们把真正的原子填上去，我们可以看出，总体来说，没错，满足规律。
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All right. So let's look now at the case where we do have 2 p z orbitals that we're talking about.
好的，让我们现在看一个,需要2pz轨道的例子。
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That's it. Again, these other p dxy dyz - or the d x y, d y z, those are going to be those more complicated linear combinations, you don't need to worry about them.
同样，这些p轨道,或者，它们是一些,很复杂的线性组合，你们，不用管它。
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So, you can see, it's much easier to describe that as one term, r here, instead of using both y and z.
所以，你们可以看到，用r而不是y和z来做描述，使得它变得更为简单。
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So you should know that 0 any time m is equal to zero that it's the p z.
所以当我们讨论p轨道时,只要m等于,它就是pz轨道。
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Um-hmm. So, it's going to be the y z nodal plane, or in other words, we can say it's any place where phi is equal to 90 degrees.
嗯，是ｙｚ平面，换句话说，是在phi等于９０度的面。
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The electron completely canceled out 1 it's equivalent of charge from the nucleus, such that we only saw in a z effective of 1.
电子完全抵消了来自原子核的等量电荷,这样我们仅仅看到有效的z为，在极端案例b中。
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And what we're actually talking about again is the zeffective. So that z effective felt by the 2 p is going to be less than the z effective felt by the 2 s.
我们实际上所谈论的,所以被2p感觉到的,的有效电荷量,有效电荷量小于2s感觉到。
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Now, unlike high school math or in algebra Z where you call things X and Y and Z, in programming, in computer science, you're actually dealing with humans where it's useful to have a variable name that's more descriptive than X and Y and Z.
不像高中数学或者代数中,称为X和Y和，在程序设计和计算机科学里，你实际上是在和人打交道,在这里有个描述性比xyz更强的,变量名称是很重要的。
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So we know that we can relate to z effective to the actual energy level of each of those orbitals, and we can do that using this equation here where it's negative z effective squared r h over n squared, we're going to see that again and again.
我们知道我们可以将有效电荷量与,每个轨道的实际能级联系起来，我们可以使用方程去解它,乘以RH除以n的平方,它等于负的有效电荷量的平方,我们将会一次又一次的看到它。
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