Microwave Spectrum and Centrifugal Distortion Effects of H2S

The rotational spectrum of H232S in the ground vibrational state has been studied in the 1 cm–0.39 mm wavelength region by means of tunable, high-resolution microwave spectroscopy. Thirty-one newly observed rotational transitions of H232S, 12 of which occur at frequencies higher than 600 GHz, have been combined with previous microwave measurements on this molecule in a rotation-distortion analysis of H232S which is based entirely on high precision microwave data. The results for the effective rotational constants and quartic and sextic distortion constants are (in megahertz): A = 310 182.24 ± 0.60, B = 270 884.05 ± 0.51, C = 141 705.88 ± 0.51, ΔJ = 49.851 ± 0.038, ΔJK = −159.696 ± 0.069, ΔK = 111.851 ± 0.068, δJ = −6.0191 ± 0.0050, δK = 262.17 ± 0.21, HJ = (2.813 ± 0.105) × 10−2, HJK = (−2.283 ± 0.027) × 10−1, HKJ = (4.59 ± 0.16) × 10−1, HK = (−2.765 ± 0.141) × 10−1, hJ = (−5.841 ± 0.081) × 10−3, hJK = (2.428 ± 0.052) × 10−1, and hK = 2.870 ± 0.039. In addition, a partial set of distortion terms of order P8 and P10 is found to be necessary in the analysis.