DENSITY DEPENDENCE OF THE 5-MU-M INFRARED-SPECTRUM OF NH3

Measurements of dilute mixtures of NH3 in H2 were made in the window region 1900-2100 cm-1 of the NH3 spectrum to determine its behavior with increasing pressure of H2. The spectra of pure H2, pure NH3, and mixtures of the two, in the total pressure range from 2.38 to 8.17 atm at 309 K, were obtained with a 975 cm White cell. Synthetic spectra were calculated using precise line strenghts, line positions, and a Lorentz profile. The experimental and calculated spectra are in reasonably good agreement, except that the former is super-imposed on a rather flat background not given by the calculation. A possible mechanism for this background is suggested. © 1990.