Electron of I

Because I2 has a single bond, the extra electron of I must occupy an antibonding molecular orbital. Therefore, the valence-bond structure for 1 must be the Pauling 3-electron bond structure ("I I ). By spin-pairing the unpaired electrons of Ij and McjN", we may represent MejN — 1 by the increased-valence structure (3), and describe (approximately) the electronie stmcture of the complex in terms of resonance between structures (2) and (3). 

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