Speaker
Description
The HAMP-vQED project, funded by an ERC advanced grant, aims to set new standards for highly accurate calculations of molecular properties. This includes exploring the possible role of QED-effects on properties that explore the electronic density in the vicinity of nuclei, such as the parameters of NMR and Mössbauer spectroscopies. A first line of attack has been the inclusion of effective QED-potentials in molecular calculations 1. A second, more ambitious approach is to include such effects through an effective QED-Hamiltonian. A first step in this direction involves the calculation of one-loop vacuum polarization [2,3] and electron self-energy 4 for one-electron atoms. We have imposed as constraint to work in the finite Gaussian basis sets widely used in quantum chemistry, also because we believe they can facilitate the extension of such calculations into the molecular domain. Somewhat to our surprise, our results can compete with the accuracy of conventional methods based on Green's functions.
1 Ayaki Sunaga, Maen Salman and Trond Saue, J. Chem. Phys. 157 (2022) 164101
2 Maen Salman and Trond Saue, Phys. Rev. A 108 (2023) 012808
3 Ryan Benazzouk, Maen Salman, Trond Saue,arXiv:2512.16569
4 Dávid Ferenc, Maen Salman and Trond Saue, Physical Review A 111 (2025) L040802