The dissociation energies of the diatomic alkali hydrides

A new method for estimating the dissociation energies for the alkali hydride molecules is reported. It involves extrapolating the known Rydberg–Klein–Rees potential curve of the A 1Σ+ state to the ionic–covalent avoided crossing point. The estimate dissociation energies De(X) are 16 000±400 cm−1 for NaH, 15 020±400 cm−1 for KH, and 14 580±600 cm−1 for RbH.