Direct calculation of the S matrix in coordinate space

We test the strong approximation of the MoXller wave operator scheme in coordinate space for N-N scattering using the local Malfliet-Tjon IV potential. Using spline expansion functions we obtain a finite-dimensional Hamiltonian matrix with a band structure which brings about a considerable numerical advantage when diagonalizing it. We compute the S matrix and find satisfactory agreement with a standard solution. We also compute the violation of energy conservation