Speaker
Description
Theory can provide important support at all the stages of spectroscopic experiments, from planning the measurements, through extracting the properties of interest from the data, and to the interpretation of the results and their comparison to theoretically predicted values. To be reliable and useful in experimental context, theoretical predictions should be based on high accuracy calculations. Such calculations must include both relativistic effects and electron correlation on the highest possible level.
Relativistic coupled cluster is considered one of the most powerful methods for accurate calculations of properties of heavy many-electron systems. This approach can be used to obtain ionization potentials, electron affinities, excitation energies, hyperfine structure parameters, and other atomic properties, and a variety of molecular properties. It has been shown to be extremely reliable and to have very strong predictive power. Recently, we have developed a scheme that allows us to use extensive computational investigations to assign uncertainties on the theoretical predictions [1], facilitating the use of these predictions in experimental context.
A brief introduction to the relativistic coupled cluster method will be provided and the new development for estimation of uncertainties will be presented. The talk will focus on recent successful applications of the coupled cluster approach to atomic and molecular properties, in particular in connection to recent and planned experiments [2-3 and yet unpublished work].
[1] D. Leimbach, J. Karls, Y. Guo, R. Ahmed, et al,
The electron affinity of astatine
Nature Comm. 11, 3824 (2020)
[2] A. A. Kyuberis, L. F. Pašteka, E. Eliav, H. A. Perrett, A. Sunaga, S. M. Udrescu, S. G. Wilkins, R. F. Garcia Ruiz, and A. Borschevsky
Theoretical determination of the ionization potentials of CaF, SrF, and BaF
Phys. Rev. A 109, 022813 (2024)
[3] K. König, J. C. Berengut, A. Borschevsky, et al.
Nuclear charge radii of silicon isotopes
https://arxiv.org/abs/2309.02037
