Let's look at the energetics of one of those electrons crashing into a hydrogen atom inside the gas tube.
我们一起来考察一下,其中的一个电子的能量,在阴极射线管中,撞击到氢原子上。
So, last date we were looking at some early taxonomy, and then on to a little bit more about the interior of the atom.
因此,最近我们了解了一下早期的分类法,以便加深,对原子内部的理解。
And when we take the wave function and square it, that's going to be equal to the probability density of finding an electron at some point in your atom.
当我们把波函数平方时,就等于在某处,找到一个电子的概率密度。
Also, when we're looking at the Schrodinger equation, it allows us to explain a stable hydrogen atom, which is something that classical mechanics did not allow us to do.
当我们看一个薛定谔方程的时候,它给出一个稳定的氢原子,这是在经典力学中做不到的。
We're going to be looking at the solutions to the Schrodinger equation for a hydrogen atom, and specifically we'll be looking at the binding energy of the electron to the nucleus.
我们将研究下氢原子薛定谔方程的解,特别是电子和核子的结合能,我们将研究这部分。
And what we've been talking about with all of these properties are, of course, how can we figure out what that is for a certain atom by looking at the periodic table, so we want to think about the periodic trend for atomic radius.
对于我们讲过的这些性质,我们所讨论的一直都是,当然是,我们如何能够判断某一个原子的这些性质,通过观察周期表,因此我们需要思考一下原子半径的周期性规律。
And what is discussed is that for a 1 s hydrogen atom, that falls at an a nought distance away from the nucleus.
我们讨论了对于氢原子1s轨道,它的最可能半径在距离原子核a0处。
What did we know at the end of the 19th century about the structure of the atom?
在19世纪末,关于原子结构我们了解多少呢?
And, I'm going to put the sodium atom at the center.
我将把钠离子放在中央。
So, if we're talking about five different orbitals and we're talking about a ground state atom, we know that we just need to start at the bottom and work our way out up.
因此,如果我们要讨论的是,五个不同的轨道且是属于一个基态原子的话,我们知道,我们只需要从最低的轨道,开始一个一个往上找。
We can also look at the energy equation now for a multi-electron atom.
我们也可以看到现在对于,一个多电子原子的能量方程。
So, one difference between photoelectron spectroscopy and, for example, the photoelectric effect is that in this case, we're not just looking at one energy level, which is what we were looking at from the surface of a metal, now we're talking about this gaseous atom.
光电子能谱与光电效应的不同点在于,以这种情况为例,我们不只关心一个能级,就像原来在金属表面那样,现在我们研究的是气体原子,所以,我们可以从原子中。
So, the example that we took on Monday and that we ended with when we ended class, was looking at the 1 s orbital for hydrogen atom, and what we could do is we could graph the radial probability as a function of radius here.
周一我们,最后讲到了,粒子是氢原子1s轨道,我们可以画出,这幅径向概率分布曲线。
So all that Bohr, for example, had to go on at this point was a more classical picture of the atom, as you can see on the left side of the screen there, which is the idea that the electrons orbiting the nucleus.
原子的经典图像,你们可以,看到屏幕左边,这是电子,绕着核子旋转,的概念,他已经知道。
So, in fact, yes, we did confirm that these covalent bond, at least in the case of hydrogen, we have confirmed by the numbers that we are at a lower energy state when we talk about the bonded atom versus the individual atom.
因此,事实上,是的,我们证实了共价键,至少在氢这种情况下,我们通过数据证实了,成键的原子处于能量更低的状态,当其与单个的原子相对比时。
So, in talking about covalent bonds, we should be able to still apply a more general definition of a chemical bond, which should tell us that the h 2 molecule is going to be lower in energy than if we looked at 2 separate hydrogen atom molecules.
那么,既然提到了共价键,我们应该还可以,给化学键下一个更普遍的定义,那就是告诉我们氢分子能量应该更低,与两个分开的氢的单原子分子相比。
Now, let's take a look at the Bohr model of the atom.
让我们看看波尔的原子模型。
So, let's look at what this actually is for what we're showing here is the 1 s hydrogen atom.
让我们来看看,我们这里给出的这个氢原子1s轨道,到底是什么。
And hydrogen atom is what we're learning about, so that's the most relevant here. But just to show you that each atom does have its own set of spectral lines, just for fun we'll look at neon also so you can have a comparison point.
为了给你们展示下每个原子,都有自己的一套谱线,仅仅是为了好玩,我们看下氖,你们可以比较一下。
And when we talked about that, what we found was that we could actually validate our predicted binding energies by looking at the emission spectra of the hydrogen atom, which is what we did as the demo, or we could think about the absorption spectra as well.
当我们讨论它时,我们发现,我们可以通过,观察氢原子,发射光谱,来预测,结合能,就像我们在演示实验里做的那样,或者我们也可以观察吸收谱。
So, for example, Wellbutrin, it is very unlikely that it would have thionyl chloride in order to make it, and if thionyl chloride was used at some point in the synthesis, it was not to put that chlorine atom on, it was to put something else on.
比如,安非他酮,用亚硫酰氯来制造它,是不太可能的,而就算在合成过程中的某一阶段用到了亚硫酰氯,它也不会把氯原子加进去,而是把其它东西加进去。
And we can look at precisely why that is by looking at the equations for the energy levels for a hydrogen atom versus the multi-electron atom. So, for a hydrogen atom, and actually for any one electron atom at all, this is our energy or our binding energy.
而且我们可以精确地看看,为什么是这样的,通过看对于氢原子和,多电子原子能级的方程所以对于氢原子,事实上对于任何一个电子,这是我们的能量或者我们的结合能。
But there's also a way to get rid of the volume part and actually talk about the probability of finding an electron at some certain area within the atom, and this is what we do using radial probability distribution graphs.
除去体积部分,来讨论,在某些区域内,发现一个原子的概率,我们可以,用,径向概率分布图,它是。
So, let's take a look here at an example of an energy diagram for the hydrogen atom, and we can also look at a energy diagram for a multi-electron atom, and this is just a generic one here, so I haven't actually listed energy numbers, but I want you to see the trend.
所以让我们来看看,一个例子氢原子的能量图,我们也可看看一个,多电子原子的能量图,这是一个普通的图谱,我没有列出能量的数字,但是我想让你们看这个趋势。
So if you picture this as our s p 2 carbon atom where we have three hybrid orbitals, and then one p y orbital coming right out at us.
如果你把这想象成sp2碳原子,这里有3个杂化轨道,然后一个py轨道朝向我们。
So, why don't you take a look at this and tell me which are possible for a 2 s electron in a lithium atom where z 3 is going to be equal to three?
你们为什么不看一下这个然后告诉我对,于一个锂原子中的2s电子哪些是可能,的?它的有效电荷量,可能等于?
So what we'll do is this problem here, which is let's calculate out what the wavelength of radiation n would be emitted from a hydrogen atom if we start at the n equals 3 level and we go down to the n equals 2 level.
我们来做这个问题,让我们来计算一下,从n等于3到,等于2能级氢原子辐射的波长是多少。
But there's something you'll note here also when I point out the case of the 2 s versus the 2 p, which is what I mentioned that I would be saying again and again, which is when we look at the hydrogen atom, the energy of all of the n equals 2 orbitals are exactly the same.
但是这里有一些事情你们也会注意到,当我指出2s和2p的情况,我之前提过,我会一次又一次的说,我们在观察氢原子的时候,2层轨道的所有n的能量,是完全相同的。
The more important thing that I want you to notice when you're looking at this wave equation for a 1 s h atom, is the fact that if you look at the angular component of the wave function, you'll notice that it's a constant.
我要你们注意的,更重要的一点是,当你们看到,这个氢原子1s轨道方程的时候,如果你们看,波函数,的角向部分,你们会发现它是一个常数。
So, if, for example, we were looking at a hydrogen atom in the case where we have the n equals 1 state, so the electron is in that ground state, the ionization energy, it makes sense, is going to be the difference between the ground state and the energy it takes to be a free electron.
电离氢原子所需要的能量,如果我们看n等于1的情况,电子在基态,那电离能,很合理的就是基态,和自由电子态的能量差。
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