Vibrational close coupling in the discrete basis set theory of electron-molecule scattering

The theory of low-energy electron-molecule scattering by T-matrix expansion in L² basis orbitals is generalized to include coupling with molecular vibration. A mixed basis set of scattered-electron orbitals and vibrational functions is used. The resulting integrals are shown to be only marginally more difficult than in adiabatic-nuclei theory. Possible shortcuts in the matrix inversion involved are discussed.