Knowledge Bank

Molecular interactions have been studied through investigations of the pressure broadening of individual infrared absorption lines of HCl as well as $CH4$. From a comparison of the foreign gas pressure necessary to produce equal absorption in two identical absorption cells, relative optical collision diameters of various polar and nonpolar gases are deduced. These values are compared with each other and with other published values of optical collision diameters in an attempt to extract information about the underlying interaction mechanims.