HIGH-RESOLUTION ROTATIONAL ANALYSIS OF THE V=6,7, AND 8 GE-H STRETCHING OVERTONES OF (GEHD3)-GE-70

High-resolution spectra of the upsilon = 6, 7, and 8 stretching overto nes of gaseous (GeHD3)-Ge-70 have been recorded by intracavity laser a bsorption spectroscopy. The spectra have been analyzed as symmetric-to p parallel bands. In all, 167 lines of the upsilon = 6 band, 115 lines of the upsilon = 7 band, and 96 lines of the upsilon = 8 band were le ast-squares fitted to give a set of rotational parameters with a root mean square deviation of 0.022, 0.024, and 0.030 cm(-1), respectively. Both upsilon = 6 and 7 spectra are similarly perturbed by an accident al crossing with an unknown state near J' = 5 for the upsilon = 6 stat e and J' = 7 for the upsilon = 7 state. In spite of a lower signal-to- noise ratio for the upsilon = 8 band, no perturbations are observed. T he rotational constants obtained depend linearly on the GeH stretching quantum number. From this linear relation, alpha(B) and alpha(C) are derived as 0.00847(17) and 0.00257(12) cm(-1), respectively, which dif fer greatly from previous values obtained from the analysis of the nu( 1) fundamental at medium resolution. (C) 1996 Academic Press, Inc.