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freedom856
Jan17-11, 09:41 PM
1. The problem statement, all variables and given/known data
The cation [CH2=CH-CH2]+ has a delocalized pi network that can be described using Huckel Molecular Orbital Method. Calculate the pi bonding formation energy



2. The attempt at a solution
Using matrix, energy = alpha, alpha + root2 beta , alpha-root2 beta

The pi electron bonding energy(Ebf) is equal to pi electron bonding energy(Epi)-N (alpha), where N is number of carbon atom in the molecules so

Ebf = 2(alpha+root2 beta)-3alpha
but, the suggested answer is N=2 can anyone tell me why N is 2 but not 3