High-resolution spectroscopy and preliminary analysis of the ν1/ν8 dyad of SF535Cl

The Fourier transform infrared spectrum of monoisotopic (SF5Cl)-Cl-35 has been recorded in the 650- to 960-cm(-1) region at a temperature of 203 K, a pressure of 0.2 mbar, and an instrumental bandwidth of 0.002 cm(-1). The nu (1)/nu (8) dyad near 900 cm(-1) has been analyzed with an effective Hamiltonian developed up to the fourth order and the help of a recently developed set of programs called C4 nuTDS (C-4 nu Top Data System, http://www.u-bourgogne.fr/LPUB/C4VTDS.html); 1346 transitions for nu (1), 351 transitions for nu (8), and 406 ground state combination differences have been assigned and fitted. A global fit has been obtained with an rms of 0.00082 cm(-1) for the nu (1) (a(1)) band, of 0,0011 cm(-1) for the v(8)(e) band, and of 0.00064 cm(-1) for the ground state. (C) 2001 Academic Press.