Exploring the Influence of structural variation on the solution and solid-state behaviour of cyanine

Cyanine dyes are well known and extensively studied molecules. The preparations and investigations of a wide range of dyes have been previously reported. Here several novel and known compounds have been synthesised to investigate the effect molecular structure has on their bulk-solution and solid-state behaviour. The preparations of sulfur-containing tri- and monomethine dyes were more reliable, hence the majority of these studies concerned sulfur analogues. Successful crystallisation of these products resulted in many novel crystal structures being obtained and compared. The monomethine dyes provided a simple, systematic study which could be analysed revealing relationships between the structures. The trimethine x-ray structural studies were less systematic but more varied. Despite many more structures being required, it appears that the prediction of packing structures may be possible from the molecular structure.<br/>In aqueous solution cyanine dyes are known to form supramolecular-type aggregates with and without the presence of inorganic salts. The aggregation process of several trimethine dyes was found to be accelerated by the anion of inorganic salts with di- and trivalent anions being more efficient than monovalent anions. Simple oxygen containing dyes were found not to aggregate even in the presence of salts, this suggests that the heteroatom has a crucial role in the aggregation process. The aggregation process was affected by molecular structure but these effects were not noticeable when concerned with the fluorescence yield.<br/>Electronic Lab Notebooks (ELN) have become successful in commercial companies but less so in academia. An ELN package designed primarily for use in a university research environment has been newly developed. This project involved trailing this product to test the system and provide feedback about the use. Several issues were recognized to affect the way the package functioned, but areas where improvements could be made were identified.

Name dc:type.qualificationname

Ph.D.

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

University of Southampton

Year dc:date.issued

2009

Author dc:creator

• Hallworth, Georgina Louise

Advisor dc:contributor.advisor

• Grossel, Martin