Enhanced cooling of hydrogen atoms by lithium atoms

We present calculated scattering lengths, for collisions between various is otopic forms of lithium and hydrogen atoms interacting via singlet and trip let molecular states of LiH. We demonstrate that one bound triplet level is supported for each isotopomer (LiH)-Li-7, (LiH)-Li-6, 7LiD, and (LiD)-Li-6 . We obtain large calculated triplet scattering lengths that are stable aga inst uncertainties in the potential. We present elastic and momentum transf er cross sections, and the corresponding rate coefficients, for hydrogen at oms colliding with Li-7 atoms. We suggest that enhanced cooling of trapped atomic hydrogen by Li-7 atoms is feasible.