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He said that the percent ionic character, and this is within a bond, not for a compound, for a covalent bond.
他提到离子百分数，是指一根键中，并非一个分子中。
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So let's figure out the bond order for our two molecules here that we figured out the electron configuration for.
让我们看看这里,两个分子的键序是多少。
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And I am going to superscript it molecular orbital, and this upper one, to indicate that it's antibonding, has the asterisk.
我将给分子轨道加上标，这个上标，表示反键轨道，有一个星号。
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The IgM is really five IgG-type molecules that are linked together through disulfide bonds, such that their FC portions are all pointing in and their antibody binding portions are all pointing out.
gM是由五个IgG分子组成的,IgG分子之间通过二硫键连接,免疫球蛋白尾部的FC片段都指向内侧,而抗体的抗原结合位点都指向外侧
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And so this lower level is called a bonding orbital, and it is a bonding molecular orbital.
所以能级较低的轨道叫做成键轨道，这就是成键分子轨道。
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So what we can actually directly compare is the dissociation energy or the bond strength of nitrogen versus hydrogen.
因此实际上我们可以直接进行比较,对氮分子与氢分子的离解能,或键的强度。
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The center of excess negative charge on all of the dipoles is at the very center of the molecule.
多出来的键,的负电荷中心都集中在,分子的正中间。
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And you can go ahead and tell me what you think the bond order is going to be for this molecule.
你们告诉我你觉得,这个分子的键序应该是怎样的。
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It's going to be a stronger bond because it's more stabilized when it when it comes together as a molecule.
这将是一个更强的键，因为它会变得更加稳定,在形成分子之后。
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You might have thought before we started talking about molecular orbital theory that non-bonding was the opposite of bonding, it's not, anti-bonding is the opposite of bonding, and anti-bonding is not non-bonding.
你也许在我们讨论分子轨道之前,就想过非成键时成键的反面，它不是，反键才是成键的反面，反键不是非成键。
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Whereas in molecular orbital theory, what I'm telling you is instead we understand that the electrons are spread all over the molecule, they're not just associated with a single atom or a single bond.
而在分子轨道理论里，我要告诉你们的时,我们任为电子分布在整个分子中,它们不仅仅是和,一个原子或者一个键有关。
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All right, so we can now see a little bit of what the power of molecular orbital theory is in predicting what kind of bonds we're going to see in molecules, or whether or not we'll see this bonding occur at all.
好了，我们已经可以看到一点,分子轨道理论在预测分子中,所成的键或者分子，能不能成键方面的能力了。
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And this one here, because it is at a higher energy is called antibonding molecular orbital.
这里的这个，因为处在一个较高的能级,被叫做反键分子轨道能级。
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It's also important, once we start talking about molecules, to have a way to represent them, and also to be able to look at a shorthand notation for a certain molecule and understand what the bond is.
还有很重要一点是，一旦我们开始讨论分子，我们需要有一种表示它们的方法，而且能够从中看出,某些分子的简化符号，并得知键的类型。
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And the reason we didn't do that is because we're actually going to spend much of the rest of the course relating these different properties to the properties of molecules in terms of bonding, and also in terms of chemical reactions.
我们至今没有这样做的原因是,实际上我们这门课程以后的大部分时间都将花在,如何将这些性质与分子的性质联系起来,在成键以及化学反应的方面。
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If we know that this is it the dissociation energy for a hydrogen atom, we can also say the bond strength for hydrogen molecule 424 is 424.
如果我们知道了这是一个氢分子的离解能,那么我们也可以说氢分子的键的强度,就是。
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We only have the one bond so the actual HF molecule is polar, it has a net dipole.
但HF中只有一根键,所以分子也是极性的而甲烷中有一个网状偶极。
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Pi orbitals are a molecular orbital that have a nodal plane through the bond axis.
轨道是沿着键轴,有节面的分子轨道。
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I want to finish this discussion by including the anti-bonding orbital, and this is a tip for you when you're drawing your molecular orbital diagrams, any time you draw a bonding orbital, there is also an anti-bonding orbital that exists.
我想要以包含反键轨道,来结束这个讨论，告诉你们一个,画分子轨道图的小技巧，任何时候你画一个成键轨道，都会存在一个反键轨道。
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So, what this lets us do now is directly compare, for example, the strength of a bond in terms of a hydrogen atom and hydrogen molecule, compared to any kind of molecule that we want to graph on top of it.
因此，这让我们现在可以做到直接进行比较，比如，将一个氢原子，和一个氢分子的键的强度，与任何其它类型的分子进行比较,我们只需要把它的曲线也画在这幅图上。
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So we'll start to look at molecules and we'll see if we take two atoms and we fill in our molecular orbital and it turns out that they have more anti-bonding orbitals than bonding, that's -- a diatomic molecule we'll never see.
我们要看开始看一看分子,并且我们会发现如果我们,取两个原子并且填入分子轨道,结果是它们的反键轨道,比成键轨道更多，这就是-一个我们不会看到的二元子分子。
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So, if we talk about dissociating h 2, we're going from the h 2 molecule, and breaking this bond right in half, so we now have two individual hydrogen atoms here.
那么，如果我们讨论的是离解氢分子，我们将从氢分子开始，使这个键断裂，一分为二，那么就得到了两个分开的氢原子。
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So we're going to finish talking about molecular orbital theory, we'll switch over to discussing bonding in larger molecules, even larger than diatomic, so we'll move on to talking about valence bond theory and hybridization.
我们要结束关于分子轨道理论的讨论，转向讨论大分子的成键，比二原子分子更大的分子，我们会继续讨论价电子成键理论,和杂化。
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If we have the molecule ethane, then what we're going to have first is our sigma bond that we described between the two carbons.
如果我们有乙烷分子，那我们首先有,碳碳之间的sigma键。
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But they're not accurate all the time in predicting bonding within molecules, and the reason for this is because Lewis structures are not, in fact, based on quantum mechanics.
但它们在预测分子内,成键时不总是正确的，这是因为Lewis结构，实际上不是基于量子力学的。
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This is sigma star with the antibonding orbital that came from 1s, and it is a molecular orbital.
这是sigma星，来自于1s的反键轨道,它是一个分子轨道。
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So far we've exclusively been using Lewis structures any time we've tried to describe bonding within molecules.
目前为止任何时候我们尝试要,描述分子内的成键,我们都是利用Lewis结构。
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So, we'll start today talking about the two kinds of molecular orbitals, we can talk about bonding or anti-bonding orbitals.
今天我们先来,讨论两种分子轨道，我们要讨论成键和反键轨道。
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we know that h is always terminal, right after the molecule that it's attached to.
我们知道氢原子永远都在末端，放到和它成键的分子的后面。
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He needs to know about the structures of the molecules, because if the structure is wrong it's not going to work.
他想要让它们成键，他需要知道分子结构，因为如果结构不对。
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