Spectroscopic observation of HD+ in the ν = 22 level

Abstract
We have observed three rotational components of the 22-17 band of the HD+ ion. The dissociation energies of 22, 0 and 22, 1 are found to be 0·438 and 0·123 cm-1. These levels are almost certainly the highest bound vibration-rotation levels of the HD+ ground state. Analysis of the nuclear hyperfine structure shows that the electron is virtually localized at the deuterium nucleus.