Study of the fundamental bands of 70GeD4 by high-resolution Raman and infrared spectroscopy:: First experimental determination of the equilibrium bond length of germane

The four fundamental bands of (GeD4)-Ge-70 have been analyzed using the STDS software developed in Dijon (http://www.ubourgogne.fr/LPUB/sTDS.html). Both infrared and Raman spectra were used to observe all fundamental bands. Infrared spectra of monoisotopic (GeD4)-Ge-70 were recorded in the regions 600 and 1500 cm(-1) using the Bruker 120HR interferometer at Wuppertal. The resolution (1/maximum optical path difference) was between 2.3 and 3.3x10(-3) cm(-1) or the nu(3) and nu(4) infrared-active fundamental bands as well as for the interacting nu(2) band. A high-resolution stimulated Raman spectrum of the nu(1) hand has been recorded in Madrid. The instrumental resolution of the Raman spectrum was 3.3x10(-3) cm(-1). We have performed a global fit of the ground state, nu(2)/nu(4) bending dyad, and nu(1)/nu(3) stretching dyad. We have used 1146, 139, and 676 assigned lines for nu(2)/nu(4), nu(1), and nu(3), respectively. The standard deviation is 2.2x10(-3) cm(-1) for the bending dyad. 1.6x10(-3) cm(-1) for the nu(3) infrared lines, and 1.7x10(-3) cm(-1) for the nu(1) Raman lines. These results enabled us to perform the first experimental determination of die equilibrium bond length of germane as r(e)=1.5173(1) Angstrom. (C) 2002 Elsevier Science (USA).