A multi reference configuration interaction study of the fine structure of the A²Π_u←X²Σ_g⁺ transition of the Si₂^- anion

Abstract

The fine structure of the A²Π_u(v=1,2)←X²Σ_g⁺(v=0) vibronic transitions of Si₂^- is evaluated theoretically by multi-reference configuration interaction computations of the potential energy curves and spin–orbit interactions for the two electronic states. The fine structure components of the two transitions are then compared to the experimental frequencies after corrections for size-consistency of energies and spin–orbit matrix elements.

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