Ricardo Esplugas- PhD Thesis- abstract
Density Functional Theory and Time-Dependent Density Functional Theory Studies of Copper and Silver Cation Complexes
- The structure, stability and spectroscopy of the following complexes have been investigated using density functional methods : [Ag pyridineN]2+, [Ag acetoneN]2+, [Ag acetonitrileN ]2+, [Cu pyridineN]2+ with 1≤ N ≤ 6; [Cu ammoniaN ]2+, [Cu ammoniaN]+ and [Cu waterN]+ with 1≤ N ≤ 8 ; [Cu waterN]2+ with 1≤ N ≤ 10 and also copper (II) phthalocyanine.
- A particular emphasis of this thesis has been to provide insight into the underlying stability of these complexes and hence interpret experimental data, and to establish the development of solvation shell structure and its effect on reactivity and excited states. Energy decomposition analysis, fragment analysis and charge analysis has been used throughout to provide deeper insight into the nature of the bonding in these complexes. This has also been used successfully to explain observed preferential stability and dissociative loss products.
- Electronic excitation spectra have been obtained using Time-Dependent Density Functional Theory (TDDFT), and this has included the evaluation of asymptotically correct functionals in addition to standard functionals. Good agreement with UV/Vis photodissociation spectra has been obtained in all cases (ranging from 0.1 to 0.3 eV). The calculation of magnetic properties focused on the determination of the Landé g factor for open-shell complexes with n=4 and 6. It was found that the g values are sensitive to both the nature of the coordinating ligands (-O or –N) and the geometry of the structure.
- The effect of relativity on all these physical properties has been considered and it is found that the effect is negligible for the Cu (I) and Cu (II) complexes but is quite significant for the Ag (II) complexes. For example, inclusion of relativistic effects in TDDFT calculations on Ag (II) complexes can shift the dominant electronic excitation energies by around 0.75 eV.
