  The multiple scattering theory (MST) is one of the most widely used methods
in electronic structure calculations. It features a perfect separation between
the atomic configurations and site potentials, and hence provides an efficient
way to simulate defected and disordered systems. This work studies the MST
methods from a numerical point of view and shows the convergence with respect
to the truncation of the angular momentum summations, which is a fundamental
approximation parameter for all MST methods. We provide both rigorous analysis
and numerical experiments to illustrate the efficiency of the MST methods
within the angular momentum representations.
