A semiclassical RKR‐like inversion procedure for determining a repulsive diatomic molecule potential energy curve from structured bound–continuum transition intensity data is derived and tested. The method presumes a knowledge of the (attractive) initial state potential well and of the energy and vibrational assignment of the absorbing or emitting level. Its application to a structured emission continuum of NaK observed by Breford and Engelke [Chem. Phys. Lett. 53, 282 (1979)] yields a potential energy curve which is incompatible with other known properties of this system, a result which confirms the suggestion of Kato and Noda [J. Chem. Phys. 73, 4940 (1980)] that the original assignment of the initial state for this spectrum is in error.

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