Molecular Engineering of Dipolar and Octupolar Non-Linear Optical Materials for Next-Generation Telecommunications
type: CreativeWork
description: In an age where next-generation all-optical circuitry and optical data storage are at the forefront of the telecommunications industry, the molecular engineering and design of new organic materials continues apace. Such materials are particularly attractive on account of their fast optical response times, and superior non-linear optical susceptibilities, relative to their traditional inorganic counterparts. While dipolar molecules dominate the field of organic non-linear optical (NLO) materials, octupolar molecules have the potential to produce far greater NLO effects; moreover, they have the capacity to produce 3-D sensitive NLO phenomena. This PhD explores new classes of dipolar organic and octupolar organometallic materials, where computations have predicted them to serve with superior NLO properties. To this end, concerted experimental and theoretical data are employed to characterise the electronic structure of these materials and elucidate their NLO properties. Data for electronic structures in this thesis were secured via in-house and synchrotron-based X-ray diffraction experiments (by proxy), which the author employed for charge density analyses. Multipolar modelling of experimental charge densities of the subject NLO materials forms an integral part of this thesis. Topological analysis is applied to these electronic structures, using the quantum theory of atoms in molecules (QTAIM), from which the structural and chemical origins of their NLO properties are assessed. Complementary theoretical methods were also used in this work, including calculations undertaken via density functional theory, as well as the relatively new technique of X-ray constrained wave-function refinement, which especially complements multipolar modelling methods, providing direct corroboratory topological analysis. An array of complementary experimental and computational methods is employed to evaluate the NLO properties of these materials in the gas-, solution-, and solid state-phase.…
abstract: In an age where next-generation all-optical circuitry and optical data storage are at the forefront of the telecommunications industry, the molecular engineering and design of new organic materials continues apace. Such materials are particularly attractive on account of their fast optical response times, and superior non-linear optical susceptibilities, relative to their traditional inorganic counterparts. While dipolar molecules dominate the field of organic non-linear optical (NLO) materials, octupolar molecules have the potential to produce far greater NLO effects; moreover, they have the capacity to produce 3-D sensitive NLO phenomena. This PhD explores new classes of dipolar organic and octupolar organometallic materials, where computations have predicted them to serve with superior NLO properties. To this end, concerted experimental and theoretical data are employed to characterise the electronic structure of these materials and elucidate their NLO properties. Data for electronic structures in this thesis were secured via in-house and synchrotron-based X-ray diffraction experiments (by proxy), which the author employed for charge density analyses. Multipolar modelling of experimental charge densities of the subject NLO materials forms an integral part of this thesis. Topological analysis is applied to these electronic structures, using the quantum theory of atoms in molecules (QTAIM), from which the structural and chemical origins of their NLO properties are assessed. Complementary theoretical methods were also used in this work, including calculations undertaken via density functional theory, as well as the relatively new technique of X-ray constrained wave-function refinement, which especially complements multipolar modelling methods, providing direct corroboratory topological analysis. An array of complementary experimental and computational methods is employed to evaluate the NLO properties of these materials in the gas-, solution-, and solid state-phase.…
author: Ashcroft, Christopher
language: eng
keywords: Molecular Egineering, Dipolar, Octupolar, NLO, Non-linear optics, Second harmonic generation, SHG
license: https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/717f3d81-8c74-416e-951f-390b1d333fff/download
license: https://www.rioxx.net/licenses/all-rights-reserved/
date published: 2018-09-27
date modified: 2026-07-22T22:24:14Z
provider: Cambridge University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Cambridge

PropertyValue
property ID: DOI
value: 10.17863/CAM.55502