The coupled channel R-matrix propagation method

Abstract

Using a Green’s function approach, we present an alternate derivation of the R‐matrix propagation equations. We also present an extension of the method which employs a basis set expansion for both translational and target motions within each R‐matrix sector. This new approach is then investigated in comparison to the original close‐coupling approach, studying a model collinear vibrational excitation problem. The new approach allows much larger R‐matrix boxes to be used in regions of configuration space where the potential is changing rapidly with the scattering coordinate.