All-electron fully relativistic Kohn–Sham Theory for solids using Gaussian-type basis functions
Marius Kadek, Michal Repisky, Marc Joosten and Kenneth Ruud
Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT The Arctic University of Norway, 9037 Tromsø, Norway
Relativistic effects are known to be important for the electronic structure and properties of compounds containing heavy elements. 1 Recently, relativistic effects have also been shown to lead to changes in the reaction mechanism of enzymatic reactions.2 Methods for calculating relativistic effects at the four component level of theory are now well developed for molecules, allowing fairly large molecules of experimental interest to be studied using four-component methodology.3
However, many compounds containing heavy elements exist as (molecular) solids. I will in this talk present a methodology for four-component relativistic density-functional theory and Hartree-Fock calculations including periodic boundary conditions.4 The approach uses Gaussian atomic basis functions and a restricted kinetic balance formalism, allowing for an all-electron description of solids while retaining computational efficiency.
In the talk, I will outline the basic features of the approach and present the first relativistic four-component calculations of molecular systems with periodic boundary conditions applied. I will also present the first relativistic four component solid-state calculations of electric field gradients at the nuclei, a property for which relativistic effects can be expected to be significant, as it probes the electron density close to the nuclei.
[1] P. Pyykkö, Ann. Rev. Phys. Chem. 63, 45 (2012).
[2] T. B. Demissie, B. D. Garabato, K. Ruud and P. M. Kozlowski, Angew. Chemie Int. Ed. 55, 11503 (2016).
[3] J. Vicha, J. Novotny, M. Straka, M. Repisky, K. Ruud, S. Komorovsky and R. Marek, Phys. Chem. Chem. Phys. 17, 24944 (2015).
[4] M. Kadek, M. Repisky and K. Ruud, in preparation.