Open AccessUncertainty assessment of Rydberg and doubly-excited molecular states ab initio calculations using Quantum Defect Theory scaling laws
Author(s) -
M. Telmini,
Ch. Jungen
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1412/13/132051
Subject(s) - excited state , ab initio , rydberg formula , diatomic molecule , scaling , ab initio quantum chemistry methods , quantum , physics , quantum mechanics , statistical physics , molecule , mathematics , ionization , ion , geometry
Synopsis We discuss the accuracy of various published ab initio calculations of highly excited Born-Oppenheimer bound and doubly excited states in diatomic molecules. We show that some of these results appear questionable and in a few cases even clearly unreliable, a fact which may also affect the prediction of collision cross sections based on such data. Our analysis uses Quantum Defect Theory scaling laws and is supported by variational R-matrix calculations. Some simple recipes are discussed, which may help users of ab initio quantum chemistry packages to assess the quality of their results.