Formation of fermionic molecules via interisotope Feshbach resonances
  We perform an analysis of recent experimental measurements and improve the lithium interaction potentials. For $^6$Li a consistent description can be given. We discuss theoretical uncertainties for the position of the wide $^6$Li Feshbach resonance, and we present an analytic scattering model for this resonance, based on the inclusion of a field-dependent virtual open-channel state. We predict new Feshbach resonances for the $^6$Li-$^7$Li system, and their importance for different types of crossover superfluidity models is discussed. 
E.G.M. v. Kempen, B. Marcelis, S.J.J.M.F. Kokkelmans