Ioniță, Cristian (2026) Relativistic coupled-cluster calculations of electron affinities and primary ionization potentials of group 7 elements. Bachelor's Thesis, Physics.
|
Text
Relativistic-coupled-cluster-calculations-of-electron-affinities-and-primary-ionization-potentials-of-group-7-elements.pdf Download (7MB) | Preview |
Abstract
The relativistic coupled cluster method in the framework of the Dirac–Coulomb (DC) Hamiltonian is employed using the DIRAC23 relativistic quantum chemistry program to calculate the electron affinities (EA) and ionization potentials (IP) of group 7 elements (Mn–Bh). The effects of basis set cardinality, electron correlation method, and relativistic treatment on the energy estimates are initially studied. The double- (DZ), triple- (TZ), and quadruple-zeta (QZ) basis sets are explored and the complete basis set limit (CBSL) is extrapolated from the TZ and QZ results. Three correlation methods are probed: Dirac–Hartree–Fock (DHF), coupled cluster with single and double excitations (CCSD), and with perturbative triple excitations (CCSD(T)). Besides the four-component (4C) DC Hamiltonian, an exact two-component (X2C) Hamiltonian and a non-relativistic (NR) Hamiltonian are considered. Group 7 elements are found to exhibit non-negligible multireference character. The EAs of the weakly bound anions furthermore prove challenging to benchmark, with the calculations for Tc–Re deviating by ca. 1 eV from reference values. The large uncertainty in the EA of Bh makes it unclear whether Bh– is bound. The IPs are within 10–15% of the experimental values, with the Bh IP agreeing with predictions given in previous reports. It is expected that multiconfigurational calculations, potentially including higher-order excitations, can result in improved estimates.
| Item Type: | Thesis (Bachelor's Thesis) |
|---|---|
| Supervisor name: | Borschevsky, A. and Boer, D. |
| Degree programme: | Physics |
| Thesis type: | Bachelor's Thesis |
| Language: | English |
| Date Deposited: | 05 Aug 2026 06:51 |
| Last Modified: | 05 Aug 2026 06:51 |
| URI: | https://fse.studenttheses.ub.rug.nl/id/eprint/37484 |
Actions (login required)
 |
View Item |