Near-Infrared Laser Spectroscopy of TiS: The b(1)Pi-X(3)Delta Transition.

Laser-induced fluorescence spectrum of TiS in the 769-863 nm region has been recorded and analyzed. The TiS molecule was produced using the technique of laser vaporization/reaction with supersonic cooling. Twenty-one weak subbands have been assigned as being due to b(1)Pi-X(3)Delta, B(3)Pi(0)-X(3)Delta(1), and C(3)Delta-X(3)Delta transitions. Strong evidence shows that the b(1)Pi state is responsible for perturbing the v = 0, 1, and 2 levels of the C(3)Delta(1) subband. The molecular constants of the b(1)Pi state have been determined as follows: T(e) = 10 589.47 cm(-1), omega(e) = 542.14 cm(-1), omega(e)x(e) = 3.16 cm(-1), B(e) = 0.19568 cm(-1), and alpha(e) = 0.00085 cm(-1). The spin-orbit interaction between the b(1)Pi (v = 2 and 3) and C(3)Delta (v = 1 and 2) levels is discussed in terms of configuration interaction occurring between the b(1)Pi from the 11varsigma(1) 5pi(1) configuration and the (1)Pi from the 5pi(1) 1delta(1) configuration, and the C(3)Delta state from 12varsigma(1) 1delta(1) configuration. Copyright 2000 Academic Press.