Knowledge Bank

The first overtone transitions of the alkali halides LiBr and NaF have been Observed in absorption using a diode laser spectrometer near $10\mu m$. Both species were produced in the gas phase in a heat pipe oven at temperatures from $800\mathrm{<mrow\; data-mjx-texclass="ORD">\circ </mrow>}C$ for LiBr to $1000\mathrm{<mrow\; data-mjx-texclass="ORD">\circ </mrow>}C$ for NaF. Numerous hot bands were observed (upto 9-7) due to the high temperature and the increase in the transition strength of the overtones with increasing v. Molecular constants and RKR curves for the $x1\Sigma +$ states of LiBr and NaF will be presented.