这个想法是由化学中的化学键理论想到的。在这个理论里，人们通常认为原子中形成满壳层的电子对化学键完全没有贡献。

The idea was suggested by the chemical theory of valency in which one is used to the idea of electrons in an atom forming closed shells which do not contribute at all to the valency.

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遗憾的是，一秒钟的标准定义依赖于原子在绝对零度的条件，而实际的时钟需要在室温下运行，室温条件下电子壳层膨胀了。

Unfortunately, the standard definition of a second relies on what the atom does at a temperature of absolute zero. Real clocks need to run at room temperature, where the shell of electrons puffs up.

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含有铁、钯、铂和稀土元素的化合物呈现强顺磁性，因为这些元素的原子有不完全的内电子壳层。

Compounds containing iron, palladium, platinum, and the rare-earth elements exhibit strong paramagnetism because they have atoms with some incomplete inner electron shells.

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So here we're talking about v plus 1, so if we were to write it just for the neutral electron itself, we would find that the electron configuration is argon, that's the filled shell in front of it.

这里我们要分析的是正一价的钒离子，因此，我们先写出中性原子的电子排布，可以发现，其原子实是氩原子的电子排布，这些壳层已经被占满了。

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