  The layered lithium borocarbide LiBC, isovalent with and structurally similar
to the superconductor MgB2, is an insulator due to the modulation within the
hexagonal layers (BC vs. B2). We show that hole-doping of LiBC results in Fermi
surfaces of B-C p sigma character that couple very strongly to B-C bond
stretching modes, precisely the features that lead to superconductivity at Tc =
40 K in MgB2. Comparison of Li{0.5}BC with MgB2 indicates the former to be a
prime candidate for electron-phonon coupled superconductivity at substantially
higher temperature than in MgB2.
