Document Type
Thesis
Date of Award
2024
Degree Name
Master of Science (MS)
Department
Chemistry
First Advisor
Bess Dr. Vlaisavljevich
Abstract
Volatile lanthanides have been proposed for applications such as chemical vapor deposition precursors and facilitating f-element separations. The latter is motivated by their broad use in technological applications. In collaboration with synthetic chemists, we studied Ln-complexes with functionalized forms of the bulky tris[(4-hydroxy-pentenylidene-2-imino)ethyl]amine (TRAC) ligand. Five ligands, labeled Yb(CH3,CH3TRAC), Yb(CH3,CF3TRAC), Yb(CF3,CF3TRAC), Yb(CF3,C3F7TRAC) and Nd(tbu,C3F7TRAC) were synthesized and volatile Ln complexes were obtained. However, the temperature at which they sublime was not sufficiently low for industrial applications. Therefore, this work examined the experimentally characterized Yb(CH3,CH3TRAC), Yb(CH3,CF3TRAC), Yb(CF3,CF3TRAC), Yb(CF3,C3F7TRAC) and Nd(tbu,C3F7TRAC) in detail. The importance of interactions between two neighboring molecules in the solid state was examined. Then the energies were used to approximate the lattice energy in the solid. These results reproduce the experimental trend in volatility and allow one to understand the stabilizing interactions present in the less volatile complexes. Next, a series of ligand modifications were performed. The first set systematically change the size of the ligands, varying steric contributions, and the degree of fluorination. A final ligand substitution, in which the tertiary nitrogen is replaced by the carbon with a CF3 group was proposed. The overall goal of this work was to model the thermodynamics of the sublimation, and our results demonstrate that simple models can be used for systems such as these.
Subject Categories
Chemistry
Keywords
Volatile lanthanides
Number of Pages
55
Publisher
University of South Dakota
Recommended Citation
Mahfuzul Alam, Kh, "THE IMPACT OF FLUORINATION ON THE VOLATILITY OF A SERIES OF LANTHANIDE COMPLEXES" (2024). Dissertations and Theses. 276.
https://red.library.usd.edu/diss-thesis/276