Energy of dissociation from continuous absorption

To calculate the dissociation energy of Big from the limit of continuous absorption. 

The potential curves of the normal state and an excited 11 state are shown schematically in fig. 1. As the steep part of the upper 

The normal state dissociates into two normal Br atoms, in P  

The wave-number of the continuous absorption limit is a measure of the energy increase in the process 

Brj (normal) - Br (normal) -f- Br (normal) we have to subtract the excitation energy of the process Br (normal) - Br (excited) 

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