Infilling of Vector Collision-Sequence Interference Dips in Collision-Induced Spectra

The vector interference dip most clearly seen in the fundamental collision induced band of H-2 and H-2 mixtures at densities upward of 20 amagat, is well known to persist at densities down to 1 amagat. However, At lower densities it is not seen. Lewis and Herman gave a theory of this infilling. In this work we approach the problem from the simple statistical models for collision induced absorption introduced by Lewis in 2000 and subsequently much elaborated. The statistical model shows infilling, but rather than a uniformly infilling dip the model shows a small central peak forming in the dip, then broadening with increasing amplitude.