So, when we think about a bond length, this is going to be the length of our bond here, that makes sense because it's going to want to be at that distance that minimizes the energy.

因此，当我们考虑一个键的长度的时候，这就应该是我们的键长，这是合理的,因为体系会在核间距达到这一距离时,能量到达最小值。

麻省理工公开课 - 化学原理课程节选

But, of course, we want to go all the way to distance, so we take the second derivative and we have this equation for force here.

当然我们最后想要的是距离,所以我们取二阶微,分就有这个式子。

麻省理工公开课 - 化学原理课程节选

They got some number that looks like for the wavelength they got the distance from here to Chicago, and they are going to drag that through the whole calculation.

他们得到一些数,看上去像是波长，他们得到这里,到芝加哥的距离，他们把那个值,用到整个计算中。

麻省理工公开课 - 固态化学导论课程节选

So, for example, if I have a sodium ion over here, and I have a chloride ion over here, where the distance from center to center r I'm denoting as r, this is nucleus to nucleus separation.

所以，比如这有一个钠离子，和一个氯离子，它们中心与中心间的距离,我把它设为，这是原子核和原子和的间距。

麻省理工公开课 - 固态化学导论课程节选