  The relativistic J-matrix is investigated in the case of Coulomb-free
scattering for a general short-range spin-dependent perturbing potential and in
two different L2 bases. The resulting recursion relation of the reference
problem, in this case, has an analytic solution. The non-relativistic limit is
obtained and shown to be identical to the familiar non-relativistic J-matrix.
Scattering examples are given to verify the non-relativistic limit and
calculate the relativistic effects in the phase shift.
