Knowledge Bank

The recent investigation of the pressure-induced infrared absorption of the fundamental band of hydrogen in hydrogen-foreign gas mixtures in our $laboratory1$ was extended to $H2-O2$ and $H2-Xe$ mixtures at room temperature. The band was studied at a path length of 105.2 cm at various pressures of the mixtures up to 250 atmospheres for several base pressures of hydrogen. The enhancement absorption profiles of the band in $H2-O2$ mixtures show the usual pronounced splitting of the Q branch into $QP$ and $QR$, a strong $S(1)$ line and an indication of the peaks of the other $S(J)$ lines for $J=0,2$ and 3. In the enhancement profiles in $H2-Xe$ mixtures, the $S(J)$ lines are much stronger than the corresponding lines in $H2-O2$ mixtures and the $O(J)$ lines for $J=2$ and 3 appear at higher pressures; the separation between the $QP$ and $QR$ maxima is small $(\sim 25cm-1)$ and the peak intensity of the $QP$ appears to be slightly more than that of the $QR$, which is contrary to the observations in other mixtures studied so far. For each of the mixtures, the binary and ternary absorption coefficients of the band were derived from the measured integrated absorption coefficients. Applying the theory of the ``exp-4'' $model2$ for the binary molecular collisions, the quadrupolar and overlap parts of the binary absorption coefficients were separated. An analysis of the enhancement absorption profiles of the band which is in progress at the time of preparation of this abstract will also be presented.