Birge-Sponer extrapolation

Birge-Sponer extrapolation

[¦bir·gə ′spōn·ər ik‚strap·ə′lā·shən]
(spectroscopy)
A method of calculating the dissociation limit of a diatomic molecule when the convergence limit cannot be observed directly, based on the assumption that vibrational energy levels converge to a limit for a finite value of the vibrational quantum number.