Atomic structure, organic compounds valence shell electrons

Trimethylbortme Dih).2 We may assume that the methyl groups will have their usual configuration found in organic compounds. The Lewis structure of (CHj)jB will place six electrons in the valence shell of the boron atom, and in order that the-electron pairs be as fair apart as possible, the methyl groups should be located at the comers of an equilateral triangle. This results in sp2, or trigonal Ur), hybridization for the bcron atom (Fig. 6.1b). 

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