Interactions in small complexes

Harris, Joe Phillip (2015) Interactions in small complexes. PhD thesis, University of Nottingham.

[img] PDF (Thesis - as examined) - Repository staff only - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (122MB)

Abstract

High-quality potential energy curves (PECs) for several series of M+RG complexes (M = B, Be-Ra, and Zn-Hg, and RG = He-Rn) have been calculated using coupled cluster theory and large basis sets. Spectroscopic constants for these species have been calculated, and using trends in these in conjunction with orbital contour plots, partial atomic charges, and total local energy density analyses, the natures of the interactions are investigated. In general, high binding energies for rare gas complexes were obtained for many of these species. In particular, interactions between the metal cations, B+ and Be+, and the heavier rare gas atoms show very high dissociation energies, with some covalent component to the nature of bonding deduced.

The anionic MH- (M = Be-Ra) and RGH- (RG = He-Rn) series are investigated through use of high quality PECs calculated at the coupled cluster level of theory using large basis sets, with spectroscopic constants being subsequently appraised. Dissociation energies in the RGH- series are found to be weak, although reaching moderate values for the heavier rare gases. Conversely, the MH- series possess much higher dissociation energies, especially in the case of BeH-. These differences are discussed in the context of hybridisation on the Group 2 metal centres, and comparison is also made to the isoelectronic BeHe complex.

Laser ablation has been employed to produce gas-phase copper atoms suitable for study by resonance-enhanced multiphoton ionisation spectroscopy (REMPI). Since the copper atoms result from an initial copper plasma, many excited electronic states are prepared, which can yield interesting results when studied by electronic spectroscopy. REMPI spectra are presented of transitions from the ground state to the two spin-orbit split components of the low-lying 3d104p state, and to a series of higher lying 3d10nd Rydberg states. Contributions from metastable initial electronic states are also seen, and assignments discussed.

Complexes between NO and the alkanes (alkane = methane, ethane, propane, and n-butane) have been studied by REMPI via the A state, where the excitation is localised to the NO molecule. For NO-methane, only the 1:1 complex was observed, but for the longer chain alkanes additional higher-order NO-alkane(n) complexes were observed. Binding energies are deduced for the excited and ground states, and structures for these complexes elucidated, aided by use of ab initio calculations.

Item Type: Thesis (University of Nottingham only) (PhD)
Supervisors: Wright, T.G.
Stace, A.J.
Subjects: Q Science > QD Chemistry > QD450 Physical and theoretical chemistry
Faculties/Schools: UK Campuses > Faculty of Science > School of Chemistry
Item ID: 32555
Depositing User: Lashkova, Mrs Olga
Date Deposited: 30 Mar 2016 09:25
Last Modified: 11 Jun 2018 04:34
URI: https://eprints.nottingham.ac.uk/id/eprint/32555

Actions (Archive Staff Only)

Edit View Edit View