First high-resolution analysis of the 2 nu(1)(A(1)) and nu(1) + nu(3)(F-2) interacting states of (GeH4)-Ge-72 and (GeH4)-Ge-73

The spectra of germane (GeH4)-Ge-72 and (GeH4)-Ge-73 enriched up to 99.9 % were recorded with high resolution (0.003 cm(-1)) at different pressures with the Bruker IFS 125HR Fourier transform spectrometer (Nizhny Novgorod, Russia). The region of 4020-4260 cm(-1), where the 2 nu(1)(A(1)) and nu(1) + nu(3)(F-2) bands are located, was theoretically analyzed. The 2025 and 1774 transitions with J(max) = 21 were assigned to these bands of the (GeH4)-Ge-72 and (GeH4)-Ge-73 species. Rotational, centrifugal distortion, tetrahedral splitting, and interaction parameters of the (2000, A(1)) and (1010, F-2) vibrational states were determined from the fit of experimental line positions of both isotopologues. The obtained sets of 13/13 fitted parameters reproduce the initial 2025/1774 experimental line positions with a d(rms) = 2.9 x 10(-4) cm(-1) and d(rms) = 2.7 x 10(-4) cm(-1) (for (GeH4)-Ge-72 and (GeH4)-Ge-73, respectively). (C) 2019 Elsevier Ltd. All rights reserved.