DIABATIC MODELS FOR WEAKLY-BOUND STATES AND COLD COLLISIONS OF GROUND-STATE ALKALI-METAL ATOMS

We apply a simplified description to weakly bound states and cold-coll ision continuum states of pairs of ground-state alkali-metal atoms, wh ich complements the usual more elaborate coupled-channel treatment. It is based on a diabatic treatment of the transition region between the exchange-dominated interatomic distance range at small r and the hype rfine-dominated range at large r. The models contain the degenerate in ternal states approximation for H atoms as a special case.