par Henriet, C.;Verhaegen, Georges 
Référence Physica scripta, 33, 4, page (299-309)
Publication Publié, 1986
Référence Physica scripta, 33, 4, page (299-309)
Publication Publié, 1986
Article révisé par les pairs
| Résumé : | The five lowest states of both 2 Σ + and 2 π symmetries were calculated with a large STO basis set (24 σ 13π, 5δ, including Rydberg orbitals on Be and on H), over a wide range of interatomic distances. A two-step CI procedure (singles, doubles and triples over the valence shell) involving each 2899 and 4122 CSF's for 2 Σ + and 2 π states respectively was used throughout the work. The results include term energies (also of dissociation products), dissociation energies, spectroscopic constants and dipole moments. The agreement between calculated results and available experimental data indicates a precision of 400 cm -1 in the energies 0.005 Å in the equilibrium internuclear distances and 15cm -1 in the vibration frequencies. The states are analysed as a function of internuclear distance by means of their natural orbitals, and semi-quantitive information is obtained conceming the validity of the Bomappenheimer approximation for certain states at certain distances. Finally, experimental interpretations of observed anomalies are rationalized. |
