Let's start. Here is the zero. This is energy zero.

开始吧，这是0，这是能量。

麻省理工公开课 - 固态化学导论课程节选

It's much more relevant to set our zero point energy as the separation of a bond in terms of talking about the reactions that we'll usually be dealing with here.

更好的是把零点能定在,键断裂的时刻,在讨论化学反应的时候,而我们以后将经常遇到化学反应。

麻省理工公开课 - 化学原理课程节选

You know, if you want to measure the potential energy of something in a gravitational field, you have to define the zero somewhere, right, because it's arbitrary. You can set it anywhere you want. It's the same with enthalpy.

你知道，如果你想测量重力场,中某种东西的势能，你需要，在某处定义一个零点，对吧？,因为势能的值是任意的,你可以把它设定在。

麻省理工公开课 - 热力学与动力学课程节选

Well, the energy at infinity is zero -K and the energy in the ground state is minus K.

无限远处的能量值为,而基态能量值为。

麻省理工公开课 - 固态化学导论课程节选

So, for starters we'll keep that as our zero energy, we're going to change it soon to make something that makes more sense in terms of bonding, but we'll keep that as zero for now.

因此，首先我们将会保持零点能的这个定义，但很快我们就会对它进行修改,使它在讨论成键时更合理，但是目前我们还是暂时采用这种定义。

麻省理工公开课 - 化学原理课程节选

Unlike the case for energy like you've seen in lots and lots of disciplines, where you can arbitrarily set the zero in a way that makes it convenient for you.

通过无数的练习题,你们已经看到这和能量不同，对于能量我们可以任意确定,能量的零点。

麻省理工公开课 - 热力学与动力学课程节选

I want to point out that the zero energy is defined as when you have a naked proton -- where the electron has popped out -- that's what we've defined as zero energy up to this point when we're talking about single atoms.

我想指出，这里零点能的定义,是当我们只有一个裸露的质子,而没有电子时-,到目前为止对零点能一直采用这样的定义,当我们在讨论单个原子时。

麻省理工公开课 - 化学原理课程节选

Just to get you oriented, this is energy decreasing from zero to progressively negative numbers.

只是为了让你们多了解些这方面的东西，在这里能量,从0开始逐渐递减到负数。

麻省理工公开课 - 固态化学导论课程节选

And so the energy is zero because the electron is no longer bound. It is free.

所以这个系统能量为0，因为,电子不再受束缚了，它自由了。

麻省理工公开课 - 固态化学导论课程节选

We could say an energy level diagram 0 This would be energy. Here is zero.

我们可以画一个能量图,这是能量，这里是。

麻省理工公开课 - 固态化学导论课程节选

And, so you propose that there is no, that this derivative is zero, and that the internal energy is given simply by this quantity.

你认为这是零，这个微分是零，内能仅仅由,这个简单的量决定。

麻省理工公开课 - 热力学与动力学课程节选

So I said before when we were talking about single atoms, we always define the zero energy as when an electron was actually ejected, but now, when we talk about chemical reactions taking place, it's very, very rare that we're actually going to be talking about anything that gets to this point here.

我之前说过，当我们讨论单个原子的时候，我们总是把零点能,定在电子被发射出去以后，但是现在，当我们讨论化学反应发生的时候，非常非常罕见出现，确实达到,这种程度的情况。

麻省理工公开课 - 化学原理课程节选

And we wrote something that looks, the energy is equal to minus the Madelung constant times Avogadro's number, 0R0 q1 q2 over 4 pi epsilon zero R zero.

我们写下了，晶格能等于负的马德隆常数,乘以阿伏伽德罗常数，乘以q1q2除以4πε

麻省理工公开课 - 固态化学导论课程节选