You can start from one nucleus and go to the next nucleus, and there are no zero planes, no nodes, nothing.

你可以从一个核出发,看向另一个核，中间没有零平面，没有节点，什么也没有。

麻省理工公开课 - 固态化学导论课程节选

So even though we see a nodal plane down the center, I just want to really point out that it's only when we have a nodal plane in the internuclear or the bond axis that we're calling that a pi orbital.

虽然在中间有个节面，我想要指出的是,只有节面在核间轴,或者键轴上时,我们才叫它π轨道。

麻省理工公开课 - 化学原理课程节选