Convergent Close Coupling

The Convergent Close Coupling method provides a very efficient approach to the calculation of a number of (anti)electron- (anti)proton- and photon-impact collision processes in quasi one- and two-electron atomic and molecular systems. The present installation handles atomic targets and light projectiles.

The basic idea is solving the close-coupling Lippmann-Schwinger equations in momentum space. The target basis, which constitutes a complete, but discrete set of functions, is capable of describing both the bound and free states of the target. Hence, the method is capable of describing both excitation and ionization of the target when applied in a consistent manner. Numerically, the close-coupled Lippmann-Schwinger equations are reduced to a very large set of complex, algebraic equations by introducing numerical quadrature. The solution of these equations may be solved in parallel using methods such as ScaLAPACK.

  • Main Developers: Igor Bray, Dmitry Fursa, Alisher Kadyrov and collaborators at Curtin University.
  • The code is written in Fortran using a hybrid OpenMP/MPI approach.
  • Contact: Igor Bray
  • CCC website
  • CCC inputs from the NIST AMPGateway Workshop, December 2019
  • Performance