Semiclassical Approach to the Abnormal Rotation of OH(A ²Σ⁺) Resulting from H₂O Photodissociation

抄録

A model for the photodissociation of H₂O is developed and is used to predict the rotational angular momentum distribution of OH^*. The model is based on an assumption that the dissociation is a simple recoil process between a rigid rotator OH^* and an H atom. The calculated distribution in the vibrational state of OH^*(v′=0) is qualitatively in good agreement with an experimental result. This gives further support to the speculation that after the electronic excitation the H₂O molecule decomposes into a recoiling H atom and an abnormally rotating OH^* radical. In the case of v′=1, the vibrational state of the H–OH system is found to be stable, and could be a semibound state.