Theoretical Study of C2 and C2(-): X 1 Sigma(+) sub g, a 3 Pi sub u, X 2 Sigma(+) sub g, and B 2 Sigma(+) sub u Potentials

摘要

We employ multiconfigurational self-consistent field and multiconfigurational electron propagator methods to characterize the X32 sigma g+ and B sigma u+ states of C2- and the X sigma g+ and a3IIu states of C2 over a wide range of bond lengths (1.0-1.9 A). We find a systematic difference of approximately 0.3 eV in the relative positioning of our anion- and neutral-state potentials compared to the anion-neutral spacing in the best curves constructed from experimental data. Once this energy shift is taken into consideration, all four of our computed potential energy curves are in reasonably good agreement with experimental information.