Study of the upsilon 3 = 1 state of (SeF6)-Se-80 by Fourier transform spectroscopy

The Fourier transform infrared spectrum of monoisotopic (SeF6)-Se-80 has been recorded in the 760-792 cm(-1) region with an effective resolution of ca. 2.3 x 10(-3) cm(-1). The (SeF6)-Se-80 sample was prepared by burning monoisotopic Se-80 powder (99.2%) in an excess of fluorine. The analysis of infrared transitions of the nu(3) band enabled the determination of parameters of the Hamiltonian developed up to the third order and the fourth order. The standard deviation obtained is equal to 4 x 10(-4) cm(-1) for the third-order development and 3.2 x 10(-4) cm(-1) for the fourth-order development. In the two analyses, 2900 lines were assigned and fitted. (C) 1997 Academic Press.