Rotation-vibration spectrum of HT: Line position measurements of the 1-0, 4-0, and 5-0 bands

Optoacoustic techniques have been used to determine the line positions of the 1-0 fundamental and 4-0 and 5-0 overtones of the HT (¹H³H) molecule with an accuracy of better than 0.01 cm⁻¹. Comparison with line positions predicted from ab initio calculations that include adiabatic, relativistic, radiative, and nonadiabatic corrections shows disagreement outside of the experimental uncertainties.     

Infra-red absorption bands 1-0, 2-0, 3-0 and 4-0 of the two isotopic species D79Br and D81Br of deuterium bromide

High resolution spectra of the 1-0, 2-0, 3-0, and 4-0 infra-red absorption bands of the two isotopic species of deuterium bromide have been recorded up to very high J values. The equilibrium molecular parameters obtained in the analysis fit the 267 observed lines within their experimental uncertainties, and give precise calculated wavenumbers for some observed chemical laser lines of these molecules.     

Absolute wavenumber measurements of 1-0, 2-0, HF and 2-0, H35Cl,H37Cl absorption bands

Fourier absorption spectra of HCl and HF at room temperature permitted to measure 87 absolute wavenumbers. The absolute observed position of the P(6) line of the 1-0 band of HF is not in agreement with a recent heterodyne determination [3]. It is found equal to 110 725 739 ± 7.5 MHz.