Rotational and hyperfine analysis of the E2Π1/2-X2Δ3/2 electronic transition of TaO

We have recorded the E-2 Pi(1/2)-X-2 Delta(3/2) (0,0) and (1,0) bands of TaO at sub-Doppler resolution by intermodulated fluorescence spectroscopy. The data were fitted using a Hamiltonian expressed in a Hund's case (c) basis set, leading to accurate values for the rotational, lambda-doubling and hyperfine constants of the upper state, which could be definitively assigned as (2)Pi(1/2) for the first time. The E-2 Pi(1/2) state has an energy of T-0 = 15876.5764(2) cm(-1) and a vibrational interval of Delta G(1/2)= 925.3164(3) cm(-1). (C) 2014 Elsevier Inc. All rights reserved.