Knowledge Bank

The vibration-rotation band of HF, consisting as it does of a series of lines spaced at about $40cm-1$ is well suited to a study of the absorption of the individual lines especially at frequencies remote from the line center. Techniques have been developed to make such a study, and measurements have been made at many frequencies, and with different cell lengths in the region between the P(8) and R(6) lines of the fundamental. Preliminary analysis of these measurements indicates that the line breadths are J dependent. Line intensities in the P branch are stronger, and those in the R branch are weaker than are computed neglecting the vibration rotation interactions discussed by Herman and $Wallis.1$