A chemical bond in which one atom loses an electron to form a positive ion and the other atom gains to electron to form a negative ion.

一个原子失掉一个电子来形成一个正离子，另一个原子得到一个电子来形成一个负离子的化学键。

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We're going to get to more complicated atoms eventually where we're going to have more than one electron in it, but when we're talking about a single electron atom, we know that the binding energy is equal to the negative of the Rydberg constant over n squared, so it's only depends on n.

我们以后会讲到，更加复杂的情况,那时候,不只有一个原子，但当我们讲，单个原子的时候，我们知道结合能，等于,负的Rydberg常数,除以n平方，所以它仅仅由n决定的。

麻省理工公开课 - 化学原理课程节选