Theoretical investigations of Group 13 chlorometallate ionic liquids
File(s)
Author(s)
Frankemoelle, Lennart
Type
Thesis
Abstract
This study examines group 13 chlorometallate ionic liquids using a hierarchical approach to understand their structures, ion pair interactions, and speciation. It begins with a search for isolated chlorometallate species and cation conformers in both gas and liquid phases. The electronic structures of the most stable configurations are analyzed, revealing nucleophilic and electrophilic sites in anions and cations. Techniques such as Fukui functions, net atomic charge assignments, molecular electrostatic potentials, and reduced density gradient analyses offer insights into the electronic structure and interaction profiles of the ion pairs. The study identifies preferred interaction sites for anions with [C 2 C 1 Im] + and ammonium-based cations, showing that maximizing interactions enhances ion pair stability. Self-interactions within anions like [M 3 Cl 10 ] − and linear [M 4 Cl 13 ] − strengthen cation interactions.
Speciation comparisons between mass spectrometry and gas phase analysis reveal discrepancies, suggesting kinetic effects or limited thermodynamic influence in gas phase chlorometallate speciation. The perturbation of anionic speciation impacts chloroaluminate and chlorogallate systems at higher x MCl 3 values. The thermodynamic favorability of multimetallic chloroindate complexes above x InCl 3 = 0.5 remains unexplored, and the absence of pentacoordinate and hexacoordinate chloroindate species at low x InCl 3 is plausible. For chloroaluminate and chlorogallate systems, agreement with mass spectrometry is observed below x MCl 3 = 0.67. This study enhances understanding of group 13 chlorometallate ionic liquids, advancing knowledge of their structures and applications.
Speciation comparisons between mass spectrometry and gas phase analysis reveal discrepancies, suggesting kinetic effects or limited thermodynamic influence in gas phase chlorometallate speciation. The perturbation of anionic speciation impacts chloroaluminate and chlorogallate systems at higher x MCl 3 values. The thermodynamic favorability of multimetallic chloroindate complexes above x InCl 3 = 0.5 remains unexplored, and the absence of pentacoordinate and hexacoordinate chloroindate species at low x InCl 3 is plausible. For chloroaluminate and chlorogallate systems, agreement with mass spectrometry is observed below x MCl 3 = 0.67. This study enhances understanding of group 13 chlorometallate ionic liquids, advancing knowledge of their structures and applications.
Version
Open Access
Date Issued
2023-05-31
Date Awarded
01/11/2024
License URL
Advisor
Hunt, Patricia
Jelfs, Kim
Publisher Department
Chemistry
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)