Lekat, Simon
(2025).
Implementation of the CAHF/CASCI Method and Application on Actinide-DOTA Complexes.
PhD thesis, Universität zu Köln.
This is the latest version of this item.
All available versions of this item
-
Implementation of the CAHF/CASCI Method and Application on Actinide-DOTA Complexes. (deposited UNSPECIFIED)
- Implementation of the CAHF/CASCI Method and Application on Actinide-DOTA Complexes. (deposited 04 Jun 2025 06:05) [Currently Displayed]
![]() |
PDF
Dissertation_SimonLekat_Druckversion.pdf Download (3MB) |
Abstract
This thesis presents the implementation of the Configuration-Averaged Hartree-Fock (CAHF) method combined with Complete Active Space Configuration Interaction (CASCI) within the Quantum Object Library (QOL), and their application to Ac-DOTA complexes (DOTA^4- = 1,4,7,10-Tetraazacyclododecane-N,N',N'',N'''-tetraacetate). The CAHF/CASCI approach offers a computationally efficient route for accurately describing near-degenerate f-orbitals and the resulting states in lanthanide and actinide complexes. The QOL framework was extended to enable medium- and large-scale computations through a more memory-efficient integral transformation procedure. Its capabilities were further improved by introducing a unified input system, enhancing existing methods, and adding new features such as a general overlap calculation between any wave functions, a robust CASCI implementation, and the incorporation of pseudopotential (PP) spin-orbit integrals. The second part applies the CAHF/CASCI method to investigate An-DOTA complexes (for An = Pa, U, Np), focusing on ground state character, conformer stability, and ligand field splitting. Using small-core pseudopotentials (SPPs) and high-quality basis sets, a systematic trend favoring the square antiprismatic (SAP) conformer was observed, consistent with experimental findings. This study highlights the utility of the CAHF/CASCI method for exploring the electronic structure of f-element complexes and provides insights into the chemistry of actinide-DOTA systems.
Item Type: | Thesis (PhD thesis) | ||||||||
Creators: |
|
||||||||
URN: | urn:nbn:de:hbz:38-783876 | ||||||||
Date: | 2025 | ||||||||
Language: | English | ||||||||
Faculty: | Faculty of Mathematics and Natural Sciences | ||||||||
Divisions: | Faculty of Mathematics and Natural Sciences > Department of Chemistry > Institute of Theoretical Chemistry | ||||||||
Subjects: | Chemistry and allied sciences | ||||||||
Uncontrolled Keywords: |
|
||||||||
Date of oral exam: | 24 April 2025 | ||||||||
Referee: |
|
||||||||
Refereed: | Yes | ||||||||
URI: | http://kups.ub.uni-koeln.de/id/eprint/78387 |
Downloads
Downloads per month over past year
Export
Actions (login required)
![]() |
View Item |