Ab initio multiconfigurational calculations of experimentally significant energy levels and transition rates in Lr i ( Z = 103 )

Large-scale multiconfigurational calculations are conducted on experimentally significant transitions in Lr I and its lanthanide homologue Lu I, exhibiting good agreement with recent theoretical and experimental results. A single reference calculation is performed, allowing for substitutions from the core within a sufficiently large active set to effectively capture the influence of the core on the valence shells, improving upon previous multiconfigurational calculations. An additional calculation utilizing a multireference set is performed to account for static correlation effects which contribute to the wave function. Reported energies for the two selected transitions are 20 716 ± 550 c m − 1 and 28 587 ± 650 c m − 1 for 7 s 2 8 s 2 S 1 / 2 → 7 s 2 7 p 2 P 1 / 2 o and 7 s 2 7 d 2 D 3 / 2 → 7 s 2 7 p 2 P 1 / 2 o , respectively.