High-resolution Fourier transform spectroscopy and Laser-induced fluorescence have been performed on LiCa in the infrared spectral range. We analyse rovibrational transitions of the – system of LiCa and find the state to be perturbed by spin–orbit coupling to the state. We study the coupled system obtaining molecular parameters for the and the state together with effective spin–orbit and spin–rotation coupling constants. The coupled system has also been evaluated by applying a potential function instead of rovibrational molecular parameters for the state . An improved analytic potential function of the state is derived, due to the extension of the observed rotational ladder.