Open AccessBenchmark calculations of ro-vibrational spectrum of HeH − and its isotopologues
Author(s) -
Ewa Palikot,
Monika Stanke,
Ludwik Adamowicz
Publication year - 2020
Publication title -
journal of physics. b, atomic molecular and optical physics/journal of physics. b, atomic, molecular and optical physics
Language(s) - English
Resource type - Journals
eISSN - 1361-6455
pISSN - 0953-4075
DOI - 10.1088/1361-6455/abb126
Subject(s) - isotopologue , physics , atomic physics , adiabatic process , ion , hamiltonian (control theory) , dissociation (chemistry) , spectral line , gaussian , quantum mechanics , chemistry , mathematical optimization , mathematics
Benchmark variational calculations of the Born–Oppenheimer potential energy curve (PEC) performed with explicitly correlated all-electron Gaussian functions with shifted centers are presented. The PEC energies include the leading relativistic and quantum-electrodynamics corrections and the first-order corrections due to adiabatic effects. The PEC is used to calculate the ro-vibrational spectra for HeH − and its isotopologues. The results show that these systems are marginally stable and have two to four bound vibrational levels and, for each vibrational level, a few bound rotational levels lying below the dissociation threshold. This indicates a possibility of detecting the HeH − anion in the laboratory and, perhaps, even in the interstellar space.