ANALYSIS OF THE INFRARED SPECTRUM OF THE $\nu_{2} + \nu_{6}$ COMBINATION BENDING MODE OF $H_{2}O_{2}$ AT $2649 CM^{-1}$

$^{1}$R.L. Redington, W.B. Olson and P.C. Cross, J. Chem. Phys. 36, 1311 (1962) $^{2}$P. Helminger, W.C. Bowman, and F.C. DeLucia, in Press.Author Institution:The infrared spectrum of the $2649 cm^{-1}$ combination bending mode of hydrogen peroxide has been recorded with resolution of about $0.05 cm^{-1}$. This considerably higher than the $0.2 cm^{-1}$ resolution obtained for the same band system by Redington, Olson and $cross^{1}$. Our higher resolution reveals that the spectrum is actually that two hybrid bands (A + B type). The center of the $\tau^{\prime\prime} =1,2\rightarrow \tau^{\prime} =1,2$ band is at $2649.018 cm^{-1}$ and the center of the $\tau^{\prime\prime}=3,4 \rightarrow \tau^{\prime}=3,4$ band is at $2649.271 cm^{-1}$. Most of the assigned lines of Redington, Olson and Cross, while correctly identified, were unresolved doublets, and the ground state constants obtained by these workers represent a non-liner average of constants over the $\tau^{\prime\prime}=1,2$ and $\tau^{\prime\prime}=3,4$ grund torsional states. Both component bands of the weak overtone $2\nu_{2}$ have also been identified, and a tentative identification of one component of $2\nu_{6}$ has also been made. Combination differences form the present work will be combined with recent extensive microwave $measurements^{2}$ to give improved molecular constants, particularly $D_{K}$ and the $\tau^{\prime\prime}=1,2$ to $\tau^{\prime\prime}=3,4$ torsional splitting