COMBINATION BANDS OF $D_{2}O$ AND $HDO^{\ast}$

Abstract

Author Institution: National Bureau of Standards; The Johns Hopkins UniversityThe absorption spectra of $D_{2}O$ and mixtures of heavy and light water vapor have been measured between 1.2 and $2.8 \mu$. With the 15,000 line/inch grating, effective slits of about $.15 cm^{-1}$ could be used, resulting in considerably better resolution and greater detail than in any previously reported bands of $D_{2}O$ and HDO. A multiple reflection cell with a path of 6 meters was used, heated to about $70^{\circ}C$ in order to increase the density of the absorbing molecules. The analysis of the 101 and 111 bands of $D_{2}O$ at 5373.6 and $6533.4 cm^{-1}$, respectively, have been verified and $extended^{1,2}$ and we have observed and analyzed two new bands of this molecule, 011 at $3956.3 cm^{-1}$ and 201 at $7899.7 cm^{-1}$. The analyses have been extended to higher J-values than in previous work and yields improved rotational constants. We have also observed and measured a number of lines attributed to be HDO molecule, particularly in the regions centering about $4105 cm^{-1} (\nu_{1} + \nu_{2}$) and $5103 cm^{-1} (\nu_{2} + \nu_{3}$) and $6460 cm^{-1}$. The rotational analysis of these bands is in progress and will be reported on