HIGH-RESOLUTION STUDY OF THE NU(2), 2-NU(1), NU(1)-NU(3) BANDS OF HYDROGEN TELLURIDE - DETERMINATION OF EQUILIBRIUM ROTATIONAL-CONSTANTS AND STRUCTURE(NU(3), AND 2)

High resolution Fourier transform spectra of a natural and a Te-130 mo noisotopic sample of H2Te have been recorded at a resolution of 0.0022 cm(-1) in the 11.6 mu m spectral region, as well as a spectrum of a n atural sample of H2Te at a resolution of 0.0051 cm(-1) in the 2.4 mu m region. In the 11.6 mu m region the main absorbing band is the nu(2) band, the analysis of which was rather easy. On the other hand, in the 2.4 mu m region three bands are absorbing, namely 2 nu(1), nu(1) + nu (3), and 2 nu(3), the last being much weaker than the others. The anal ysis in this spectral domain was much more difficult because of resona nces, Indeed it proved not possible to reproduce the observed lines wi thout taking into account the Darling-Dennison interaction between the levels of the (200) and (002) states and the Coriolis interactions be tween the levels of(200) and (101) and between those of (101) and (002 ). Considering these interactions allowed us to calculate very satisfa ctorily all the experimental levels, and precise sets of vibrational e nergies and rotational and coupling constants were obtained for the se ven most abundant H2Te Isotopic species, namely (H2Te)-Te-130, (H2Te)- Te-128, (H2Te)-Te-126, (H2Te)-Te-125, (H2Te)-Te-124, (H2Te)-Te-123 and (H2Te)-Te-123. For the most abundant species, (H2Te)-Te-130, the band centers in cm(-1) are nu(0)(nu(2)) = 860.6563, nu(0)(2 nu(1)) = 4062. 8542, nu(0)(nu(1) + nu(3)) = 4063.3697, and nu(0)(2 nu(3)) = 4137.0454 , These results, combined with those obtained for other vibrational st ates, have been used to derive the equilibrium rotational constants an d their corrections. Finally, by neglecting the electronic corrections , the equilibrium structure of (H2Te)-Te-130 was obtained as follows: r(e) (Te-H) = 1.65 145(10) Angstrom, alpha(e) (HTeH)= 90.2635(90)degre es. (C) 1997 Academic Press.