EXACT-EXCHANGE TREATMENT IN ELECTRON POLYATOMIC MOLECULE COLLISIONS IN A COMPUTATIONALLY OPTIMIZED ITERATIVE SCHEME

We suggest here a computationally optimized scheme in which the iterative procedure can be efficiently employed to treat exchange-correlation exactly in electron-polyatomic molecule collisions. The new scheme is more suitable for polar species. First, it adequately solves integro-differential coupled equations for only a few low partial waves for the exact-exchange treatment. Second, the continuum function determined iteratively at any one energy is a good starting point to start iteration at other energies. Some test results are presented for the e-H2O system in its A1 symmetry at the static-exchange level.