Structure and properties of dioxygen

Molecular oxygen (or dioxygen) O2 and related species are involved in many chemical reactions. The valence molecular orbitals and electronic configurations of the homonuclear diatomic species O2 and Oj are shown in Fig. 16.1.1. 

In the ground state of O2, the outermost two electrons occupy a doubly degenerate set of antibonding tt orbitals with parallel spins. Dioxygen is thus a paramagnetic molecule with a triplet ground state (3 ), and its formal double bond has a length of 120.752 pm. 

Owing to its nonpolar nature, O2 is more soluble in organic solvents than in H2O. Since the 3 ground state of dioxygen is a spin triplet, concerted oxygenation reaction is subject to spin restriction. As a result, many types of dioxygen reactions proceed slowly, even in cases where such reactions are 

Species Compound Bond order 0-0 (pm) Bond energy (kJ mol-1) v (0-0) (cm 1) 

Another source is derived from phosphite ozonides as in the reaction 

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