And the reason is simply because the energy that Z we gain in terms of moving up in z, 5 so from going to z equals 4 to z equals 5, -- is actually outweighed by the energy it takes to go into this new shell, to go into this new sub shell.

原因很简单,就是因为我们通过提升，所得到的能量--从，Z，等于，4，到，Z，等于，事实上比填充到这个新的壳层,新的亚壳层，所消耗的能量更多。

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