Infrared Spectrum of Hydrogen Sulfide in the 2.6-Micron Region

The infrared absorption spectrum of hydrogen sulfide (H₂S), in the region from 3730 cm^—1 to 4030 cm^—1, has been measured under high resolution. Calibration was made from emission lines of argon, observed in the second order, using Edser‐Butler bands. The absorption has been assigned to two overlapping combination bands, a type A band (n₁,n₂,n₃) = (0,1,1) at 3789.07 cm^—1, and a type B band (1,1,0) at 3779.23 cm^—1, plus overlapping water vapor absorption. The excited state inertial parameters in cm^—1 giving the best fit to the data were found to be $$\begin{array}{cccc}& A^{*}& B^{*}& C^{*}\\ \text{(0,1,1)}& \text{10.517}& \text{9.124}& \text{4.619}\\ \text{(1,1,0)}& \text{10.595}& \text{8.985}& \text{4.603}\end{array}$$