OBSERVATION OF TIF-X-3-PHI SYSTEM( BY VELOCITY MODULATION LASER SPECTROSCOPY AND ANALYSIS OF THE [17.6](3)DELTA)

The molecular ion TiF+ has been observed for the first time using high -resolution spectroscopy. The ions were produced in the positive colum n of an AC glow discharge with a gas mixture of He/TiF4. A single-mode cw dye laser along with the velocity modulation detection technique w as used to record an absorption spectrum in the spectral region 16 800 -18 600 cm(-1). The observed system was assigned to the 0-0 and 1-1 ba nds of the [17.6](3) Delta-X-3 Phi transition of TiF+. The rotational analysis of the main subbands has been performed up to J values equal to 77 and 56 for the 0-0 and 1-1 bands, respectively. Despite a carefu l search, no intercombination band was observed. A set of effective mo lecular parameters has been determined, characterizing the v = 0, 1 le vels of the [17.6](3) Delta and X-3 Phi states. The spin-orbit constan ts A(e) and the vibrational constants omega(e), omega(e)x(e) have been estimated for both electronic states, as well as their equilibrium di stances R-e (1.7509(1) and 1.7800(1) Angstrom for the [17.6](3) Delta and X-3 Phi states, respectively). (C) 1998 Academic Press.