  We present the first high-resolution spectroscopic study of LiCs. LiCs is
formed in a heat pipe oven and studied via laser-induced fluorescence
Fourier-transform spectroscopy. By exciting molecules through the
X$^1\Sigma^+$-B$^1\Pi$ and X$^1\Sigma^+$-D$^1\Pi$ transitions vibrational
levels of the X$^1\Sigma^+$ ground state have been observed up to 3cm^{-1}
below the dissociation limit enabling an accurate construction of the
potential. Furthermore, rovibrational levels in the a$^3\Sigma^+$ triplet
ground state have been observed because the excited states obtain sufficient
triplet character at the corresponding excited atomic asymptote. With the help
of coupled channels calculations accurate singlet and triplet ground state
potentials were derived reaching the atomic ground state asymptote and allowing
first predictions of cold collision properties of Li + Cs pairs.
