Laboratory measurements of rotational transitions of lithium hydride in the far-infrared

We report laboratory frequency measurements of 14 pure rotational transitions of (LiH)-Li-7 and (LiH)-Li-6 in the fundamental and in the first two excited vibrational states. Data have been taken with a tunable far-infrared spectrometer in the 400-3000 GHz frequency range. We also discuss the astrophysical and cosmological relevance of LiH.