Crowley said the fact that diplomatic note from Tehran did not address concerns about Iran's nuclear ambitions is one reason why an exploratory meeting with the Iranians is so important.

VOA: standard.2009.09.11

But they're not accurate all the time in predicting bonding within molecules, and the reason for this is because Lewis structures are not, in fact, based on quantum mechanics.

但它们在预测分子内,成键时不总是正确的，这是因为Lewis结构，实际上不是基于量子力学的。

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