Pi orbitals are a molecular orbital that have a nodal plane through the bond axis.

轨道是沿着键轴,有节面的分子轨道。

youdao

So PI bonds have electron density both above and below the bond axis, but they actually have a nodal plane at this z, this bond axis here.

键在键轴之上，和之下都有电子密度，但它们在z方向有节面，这是键轴的地方。

youdao

Sigma as being cylindrically symmetric about the bond axis, and it's important to point out that it has no nodal plane across this bond axis.

键是，So, we, talk, about, a, sigma, bond，关于键轴圆柱对称的，需要着重指出的是，而且沿着键轴是没有节面的。

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。

麻省理工公开课 - 化学原理课程节选

Pi orbitals are a molecular orbital that have a nodal plane through the bond axis.

轨道是沿着键轴,有节面的分子轨道。

麻省理工公开课 - 化学原理课程节选

So pi bonds have electron density both above and below the bond axis, but they actually have a nodal plane at this z, this bond axis here.

键在键轴之上,和之下都有电子密度，但它们在z方向有节面，这是键轴的地方。

麻省理工公开课 - 化学原理课程节选

The highlight of the show was Craig, as Bond, walking into Buckingham Palace, escorting The Queen to a plane and then both of them apparently parachuting out of the plane into the opening ceremonies.

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