Non-Standard Crystallography : Examples in 3- and 3+1 Dimensional Space

Crystallography today is by many seen as merely a tool for determining the structure of a material on the atomic level. It is expected that whatever comes out of the tool is the indisputable truth, a fact. This thesis is based on five publications illustrating that this is very far from the real wor...

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Bibliographic Details
Main Author: Christensen, Jeppe
Format: Doctoral Thesis
Language:English
Published: Stockholms universitet, Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi 2007
Subjects:
Online Access:http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7194
http://nbn-resolving.de/urn:isbn:978-91-7155-524-3
Description
Summary:Crystallography today is by many seen as merely a tool for determining the structure of a material on the atomic level. It is expected that whatever comes out of the tool is the indisputable truth, a fact. This thesis is based on five publications illustrating that this is very far from the real world of materials research. The experiences drawn from the structural work in the papers are put together to illustrate when to be alert, and how to proceed with a structural investigation using non-standard crystallography. The focus is on interpreting the signs of additional order being present in a structure. The signs may be weak, such as extreme thermal vibration, or unit cell deformation. Or the signs can be strong, with superstructure reflections indicating the presence of either commensurate or incommensurate superstructures.