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So it doesn't matter how big the dictionary is, you can instantaneously retrieve the value associated with the key. Extremely powerful.
因为你可以在线性时间，内得到想要的键对应的值,这太强大了。
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And what you find is when you have a bonding orbital, the energy decreases compared to the atomic orbitals.
你们发现当你有个成键轨道的时候，相比原子轨道能量要降低。
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If I have one that's 400 kilojoules per mole and another that's 200 kilojoules per mole and I blend them, how do I get 500 kilojoules per mole?
如果你有一个每摩尔400千焦的分子,和一个没摩尔200千焦的分子,我把它们并子一起，我怎么得到每摩尔500千焦的键？
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What you can do is you can iterate keys, which gives you the keys in the dictionary, and then you can choose them, but there's no guarantee in the order in which you get keys.
你能做的就是迭代得到键，这样就可以得到字典中，所有的键并进行选择，但是键的顺序,是没有保证的。
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So in a moment you're going to go ahead and hit the spacebar and then as things fall from the screen when they line up with the left arrow, hit the left arrow with a different arrow, hit that arrow and see how good a score you can get.
一会儿你走到前面，敲一下空格键,当屏幕上面的东西从左边往下掉的时候,你就敲一下键盘上的左键,是哪个方向，敲对应的方向键就可以了,我们来看看你能得多少分。
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So any time you have two atoms bonding, the bond axis is just the axis that they're bonding along.
任何时候如果你有两个原子成键，键轴就是它们成键的方向。
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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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So you can see that this is non-bonding, this is even worse than non-bonding, it's anti-bonding, because we're actually getting rid of electron density between the two nuclei.
所以你可以看到这是不成键的，它甚至比不成键还糟糕，它是反键，因为我们实际上是去掉了,两个原子核之间的电子。
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So it's trigonal because we have these three atoms that are bound to the central atom here, and if you picture it, it's actually shaped like a pyramid.
这里三角形是因为,我们有3个原子核中心原子成键，如果你画它，它就是金字塔形的。
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So in order to rotate a double bond, you have to actually break the pi bond, so essentially what you're doing is breaking the double bond.
为了能够旋转双键，你必须打破一个π键，本质上我们要做的就是打破双键。
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And the bond order you get out will either be, for example, zero, which would mean that you have no bond, 5 or you could have 1, a single bond, 1 . 5, a 1 and 1/2 bond, 2, a double bond, and so on.
你得到的键序要么是比如说是零，这意味着没有键，或者你会得到1，单键1。,1又二分之一键，2，一个双键，等等等等。
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So I hit control X. It's very unnecessarily arcanely saying save modified buffer, and then answering no will destroy changes.
敲入控制键X，它会很罗嗦地,问你是否保存所做的修改,如果回答为NO，就不保存修改过的部分。
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If we think about bringing in those last two carbons, what you can see is that for every carbon, two of its hybrid orbitals are being used to bond to other carbons.
如果我们考虑引入最后两个碳原子，你会看到的是对于每个碳原子，其中的两个杂化轨道,和另外的碳原子成键。
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When you are done you have three electron pairs in bonding orbitals.
当你完成的时候,成键轨道上共有三对电子。
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Remember this is our bond axis here, and you can see there is this area where the wave function is equal to zero all along that plane, that's a nodal plane.
记住这是我们的键轴，你可以看到在这些区域,波函数在这个面内全都是零，这是节点面。
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We can know this information even if we just knew that the bond was stronger, we wouldn't need to look at a graph here, because it turns out that if you have a stronger bond, -- that also means that you have a shorter bond -- those two are correlated.
我们依然可以得到上面的信息,即使我们所知道仅仅是这个键更强，我们不需要去看这个图，因为事实上如果你有一个更强的键，这也就意味着你有一个更短的键-,这两点是互相关联的。
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You have two electrons in antibonding to kind of offset the bonding.
你有两个电子,在远离成键轨道的反键轨道上。
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And if you've never used those, they're usually above your Return key.
如果你从来没用过这些竖线，它们在,回车键的上面。
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So if you're trying to make a more complicated organic molecule carbon-carbon bonds are one of the most difficult things to make in organic chemistry, and it turns out that c n minus is a very reactive molecule, so it's a good way, even though we'll go over some drawbacks in a second, it is a good way to make carbon-carbon bonds.
如果你要合成一个更复杂的有机分子,碳碳键是有机化学中,最难制造的键之一，而实际上氰离子是一种具有很高活性的分子，用它是一个好办法，尽管我们一会儿将看到它的一些缺点，但它的确是一个制造碳碳键的好方法。
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So for some you that are less interested in maybe the physical structure of an individual atom, now some more exciting material for you might be coming up if you like to think about how, instead, molecules behave, either within bonding, within themselves, or with other molecules, that's what we're going to be heading to in this next unit.
那么对于某些同学，你们或许不感兴趣,对于单个原子的物理结构，现在可能有令你感到兴奋的内容,要出现了，如果你更喜欢思考,分子的行为，或者是关于成键的，或者是关于它们本身的，又或者与其它分子之间的行为，这些将是我们下个单元要讲的内容。
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But since in drawing Lewis structures actually, in some cases you do, you can draw a dotted line that means a 1 and 1/2 bond, but most in most cases, we just draw out both resonance structures, and the way that we say it's a resonance structure is that we put it in the brackets and we put an arrow between it.
但是由于在画路易斯结构时,其实，在某些情况下是可以的，你可以画一条虚线来表示一又二分之一键，但是在多数情况下，我们就把两个结构都画出来，而我们说这是一个共振结构的表示的方法是,把它们放在括号里，并在中间放一个双箭头。
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The reason it printed that is I accidentally had my finger on the control key, which said print the last thing you had.
这是正确显示的，原因是刚才,我不小心按住ctrl键了，也就是这会显示你最后写的东西。
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So again, this is an anti-bonding orbital, and what you see is that there is now less electron density between the two nuclei than there was when you had non-bonding.
同样的，这是反键轨道，你们看到当你有反键轨道的时候,两个原子核中间的电子密度更小了。
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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 if you picture, for example, b h 3, it's going to look like this.
如何使键劲量相互远离，我们会有平面三角形的情形，如果你想象。
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So if you've ever seen or used an old school typewriter, you might recall that when you're typing something out on an old mechanical typewriter, - when you like hit the char-- when you hit the enter key to move the head back to the left hand side to the next line or you would pull down some lever, it was really a two part process.
如果你们有谁曾经看过或用过老式打字机，可能还记得，当你在,这种老式打字机上打字的时候，当你-,敲入回车键，跳转到,下一行的最左边，或者,拉一下杆，这个需要两步走。
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Just to give you a sense of what that means, if the 264 figure is pure covalency and the 344 is partial ionic character, what fraction of the 608 is 344? 344, which is partial ionic character, 57% divided by 608 times 100 is 57%.
它只是给你一个这样的概念，264千焦每摩是完全共价成分的键能,而344是离子成分的，344除以608是多少，344，是不完全的离子特性，除以608乘以100得到。
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A TSV file, tab-separated values uses the same thing but a tab character, if you wanna output an actual tab character, the result of hitting the tab key, \t you do use backslash T. That's so those kinds of files are made.
而TSV文件，“制表符分隔“文件,顾名思义，就是用制表符来分隔每一列，如果你想输出一个真正的制表符，点击tab键，你也可以用,这就是那些文件的形成方式。
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The reason that it's sigma is if you look at the bonding axis here, is that there is no nodal plane along the bonding axis.
它是sigma键的原因是,因为如果你看键轴，上面是没有节面的。
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You can certainly hit Enter but as we saw-- seen that very quickly makes a mess of your code and such and so backslash N is new line.
你也可以敲回车键-,但是会让你的代码看起来乱七八糟,反斜杠n就是换行符。
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