The laser-induced fluorescence spectroscopy of TiF in the ultraviolet region

The laser-induced fluorescence (LIF) spectrum of jet-cooled 48TiF has been obtained in the wavelength region of 245-270 nm for the first time. Six pairs of vibronic bands were observed and assigned to two new transitions [37.8]4Φ-X4Φ and 4Δ-X4Φ. Rotational analysis was carried out for the (ν′ = 0-3 to ν″ = 0) vibrational bands of the [37.8]4Φ3/2-X4Φ3/2 and [37.8]4Φ5/2-X4Φ5/2 subbands, and also, the (ν′, 0) and (ν′+1, 0) vibrational bands of the 4Δ1/2-X4Φ3/2 and 4Δ3/2-X4Φ5/2 subbands. The effective equilibrium molecular constants for the [37.8]4Φ3/2 and [37.8]4Φ3/2 upper states were determined. In addition, lifetime measurements were carried out for all of the observed bands under collision-free conditions. On the basis of the spectroscopic constants and lifetime measurements, the electronic transitions involved in the observed high-lying electronic states are discussed.