Knowledge Bank

The first (2-0) and second (3-0) overtones of DCl have been obtained with high dispersion in the 2.4 and 1.6 $\mu$ regions. The dispersing system consisted of a recording vacuum spectrograph equipped with a 15,000-line-per-inch grating and a lead sulfide detector. Calibration was obtained by making use of the second order Argon emission lines and Fabry-Perot etalon fringes. Analysis yields molecular constants essentially in agreement with those obtained by Pickworth and $Thompson1$ for the fundamental. In addition the data yields values for the anharmonic constants. These values agree within experimental error with the calculated values as based on the data for HCl.