有时候它也叫核间轴。

Sometimes it's also called the internuclear axis.

youdao

一个三键，同样的也有沿着核间轴sigma键。

A triple bond, again is going to have one sigma bond on the internuclear axis.

youdao

任何时候两个轨道，在核间轴上直接到一起，你就能得到sigma键。

Any time two orbitals come straight on together in that internuclear axis, you're going to have a sigma bond.

youdao

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。

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If we're talking about a single bond, we're talking about 2 orbitals overlapping in the internuclear axis.

如果我们讨论的是单键，我们讨论的是两个轨道,在核间轴中重叠。

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And a sigma bond forms any time you have two orbitals coming together and interacting on that internuclear axis.

当你把两个轨道合在一起,并在核间轴上有相互作用时,就形成了sigma键。

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