Abstract
The spin-rotational Hamiltonian parameters and for the BaF molecule are calculated using four-component relativistic spinors at the second-order many-body perturbation theory (MBPT) level via the Z-vector technique. The second-order MBPT is applied to assess the accuracy of the computed hyperfine-structure constants before studying the problem with the state-of-the-art coupled cluster with single and double excitations (CCSD) method which is highly accurate but computationally more expensive than MBPT. The hyperfine-structure constants and resulted from these calculations agree favorably well with experimental findings and with other correlated calculations. The convergence behavior of and with respect to the number of active orbitals used in the perturbative calculations suggests that our estimated and values should be accurate.
- Received 1 October 2010
DOI:https://doi.org/10.1103/PhysRevA.83.022504
©2011 American Physical Society