"The book is Darwin's Universe: Evolution from A to Z, and it is a life's work,"
VOA: standard.2009.11.25
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。
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。
The power of linearity is F=k1+k2 if I come across f of x, y, z equals k1 plus k2, if it is a linear equation, I don't have to go and solve it all over again.
线性的威力是,一个方程,如果它是个线性方程,那么我就不用再去解他了。
X Y Z It's more interestingly named an X or Y or Z.
你也可以把它命名为。
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。
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。
So why don't you go ahead and identify the correct electron configuration for carbon, 6 and I'll tell you that z is equal to 6 here.
所以你们为什么不开始,而且识别碳的正确的在你们做作业方面,电子构型,我会告诉你有效电荷量是。
So, what we can do instead of talking about the ionization energy, z because that's one of our known quantities, so that we can find z effective.
我们做的事可以代替讨论电离能,因为那是我们知道的量子数之一,那是我们可以解出有效的,如果我们重新排列这个方程。
But what you should be able to do is take a look at a list of answers for what we're saying z effective might be, and determining which ones are possible versus which ones are not possible.
但是你们应该能够做到的,是看一下这个可能的,有效电荷量的答案列表,并且确定哪些是可能的,哪些是不可能的。
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。
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。
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。
px And I arbitrarily chose to put it in the 2 p x, 2pz we also could have put it in the 2 p y or the 2 p z, it doesn't matter where you double up, they're all the same energy.
我任意地选择放入至,我们也可以把它放入2py或,它与你在哪双倍填充没有关系,它们都在相同的能级。
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?
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。
So you can see if you take phi, and you move it over 90 degrees, we're right here in the y z plane.
你们可以看到,把phi转到90度,它就是yz面。
Z So it would be incorrect to try to assign this to a variable X or Y or Z, because it doesn't actually give me anything back.
这个是错误的,来赋值这个给变量X或Y或,因为它的确没有返回什么给我。
But what's important is not where that most probable radius is when we're talking about the z effective it feels, what's more important is how close the electron actually can get the nucleus.
但重要的不是,最可能半径,当我们谈论它感到的有效电荷量的时候,更重要的是,电子实际上。
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。
They're less shielded because they're closer to the nucleus, they feel a greater z effective.
它们受到少的屏蔽,因为它们离原子核更近,它们感觉到一个更大的有效电荷量。
And if we talk about m equals 0, we're looking at the p z orbital.
如果m等于0,那我们讨论的就是pz轨道。
So instead of being equal to negative z squared, now we're equal to negative z effective squared times r h all over n squared.
这里不再等于-z的平方,现在我们等于-有效的z的平方,乘以RH除以n的平方。
So, how many distinct, so again, we're talking about distinct kinetic energies, a spectrum for the element hafnium, 72 and I'll tell you here that it has a z of 72, so you don't have to spend two minutes searching your periodic table.
好,有多少分立的……还是一样,我们讨论的还是不同的动能,铪元素的光谱中出现,而且我来告诉大家铪的原子序数是,这样你就不用因为在元素周期表中找它,而花费两分钟的时间了。
z So the main idea here is z effective is not z, so don't try to plug one in for the other, they're absolutely different quantities in any case when we're not talking about a 1 electron atom.
所以这里主要的观点是有效的z不同于,所以不要尝试将一个插入到另一个,当我们不在讨论1个电子的原子时,它们在任何情况下是绝对不同的量子数。
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。
So now let's look at an example where we talk about using these 2 p z orbitals, so let's look at oxygen.
现在让我们来看一个要,用到2pz轨道的例子,让我们来看一下氧。
And that's going to be equal to negative z effective squared times r h over n squared.
有效的z的平方,乘以RH除以n的平方。
And now we get the p orbitals, remember we want to fill up 1 orbital at a time before we double up, so we'll put one in the 2 p x, then one in the 2 p z, and then one in the 2 p y.
我们到了p轨道,记住在双倍填充之前,我们想要每次填充至一个轨道,所以我们在2px填充一个然后2pz填充一个,然后2py填充一个。
I'm binding a z to be some value, and then I'm going to run this.
我把z绑定到一个值上,然后运行下代码。
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