R.K. Nesbet, Stephane Mazevet, et al.
Physical Review A - AMO
Near-threshold cross sections for elastic scattering and for excitation of the 100 symmetric stretch vibrational mode of [Formula Presented] have been calculated using the energy-modified adiabatic phase matrix method. These calculations are based on fixed-nuclei R matrices at several internuclear geometries that incorporate short-range exchange and correlation effects. The representation of the polarization response of the target inside the R-matrix box is improved using an alternative numerical technique, the [Formula Presented] procedure. These calculations over a range of internuclear distances reveal unanticipated behavior of the near-threshold scattering matrix. A fixed-nuclei virtual state occurs only in a limited range of internuclear separation, changing to a weakly bound state outside this range. Thus an energy pole of the scattering matrix remains near threshold and has a large effect on both elastic and vibrational cross sections, but cannot be simply described as a virtual state. Our quantitative results, in good agreement with experiment, indicate that the present modified adiabatic methodology is adequate to treat this complex behavior. © 2001 The American Physical Society.
R.K. Nesbet, Stephane Mazevet, et al.
Physical Review A - AMO
R.K. Nesbet, Stephane Mazevet, et al.
Physical Review A. Atomic, Molecular, and Optical Physics
R.K. Nesbet, Stephane Mazevet, et al.
Physical Review A. Atomic, Molecular, and Optical Physics
S. Mazevet, Michael A. Morrison, et al.
Journal of Physics B