eTheses Repository

Development of differential evolution algorithms applied to crystal structure solution from powder diffraction data

Bell, Duncan (2012)
Ph.D. thesis, University of Birmingham.

Loading
PDF (3293Kb)Accepted Version

Abstract

An understanding of the crystal structure can aid in the rationalisation of physicochemical properties exhibited by a crystalline material. Advances in the area of direct space crystal structure solution means that it is becoming easier to determine crystal structures from powder diffraction data. However, due to the number of structural models generated during structure solution calculations, direct space methods are computationally demanding.

Work presented in this thesis reports the optimisation of a differential evolution (DE) algorithm and a cultural differential evolution (CDE) algorithm to reduce the computational demands of direct space methods. Characteristics particular to certain crystal structures are identified as having a significant effect on the efficiency and robustness of structure solution calculations by DE and CDE.

The development of a new algorithm that closely mimics the natural evolution of a species is discussed. Results presented in this thesis demonstrate that this new algorithm is significantly more efficient than the DE algorithm.

Despite the complexity of powder diffraction patterns recorded for biphasic crystalline materials, in this thesis, the successful development and application of a direct space method to the simultaneous structure solution of two crystals from a biphasic powder pattern is reported.

Type of Work:Ph.D. thesis.
Supervisor(s):Tremayne, Mary-Jane and Britton, Melanie
School/Faculty:Colleges (2008 onwards) > College of Engineering & Physical Sciences
Department:School of Chemistry
Subjects:QD Chemistry
Institution:University of Birmingham
ID Code:3942
This unpublished thesis/dissertation is copyright of the author and/or third parties. The intellectual property rights of the author or third parties in respect of this work are as defined by The Copyright Designs and Patents Act 1988 or as modified by any successor legislation. Any use made of information contained in this thesis/dissertation must be in accordance with that legislation and must be properly acknowledged. Further distribution or reproduction in any format is prohibited without the permission of the copyright holder.
Export Reference As : ASCII + BibTeX + Dublin Core + EndNote + HTML + METS + MODS + OpenURL Object + Reference Manager + Refer + RefWorks
Share this item :
QR Code for this page

Repository Staff Only: item control page