And what we say when we talk about the delta energy is I E 2 that this is going to be equal to i e 2, or the second ionization energy, or we could say the negative of the binding energy of a 2 s electron in b plus.

那么我们说,Δ，E，应该等于，或者说第二电离能，也就是正一价硼中，2，s，电子的,束缚能的负值。

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