PROSPECTS FOR BOSE-EINSTEIN CONDENSATION IN ATOMIC LI-7 AND NA-23

We have determined the scattering length of the ground state Li-7 + Li-7 singlet potential from spectroscopic data on the highest S = 0 bound states. Combining this with a previously obtained triplet value we find the first example of an alkali atom hyperfine state (the Li-7 F = 1, M(F) = -1 state) for which the scattering length is positive. This implies a stable Bose condensate in future attempts to realize Bose-Einstein condensation in a magnetically trapped ultracold gas sample. We also predict magnetic-field-dependent resonances in the collision between atoms in the hyperfine state studied.