http://hdl.handle.net/2262/18 School of Chemistry 2013-05-13T14:01:51Z http://hdl.handle.net/2262/64107 Title: Attracting Talented Researchers to Ireland: A review of The European Marie Curie Programme Author: GIORDANI, SILVIA Abstract: The purpose of this publication is to illustrate how researchers in academia and industry in Ireland have successfully secured funding from Europe in the Marie Curie Programme and to highlight the impact this has had in furthering their R&D ambitions. Description: PUBLISHED 2007-01-01T00:00:00Z http://hdl.handle.net/2262/64104 Title: Cubic Icosahedra? A Problem in Assigning Symmetry Author: LLOYD, DAVID ROBERT Abstract: There is a standard convention that the icosahedral groups are classified separately from the cubic groups, but these two symmetry types have been conflated as “cubic” in some chemistry textbooks. In this note, the connection between cubic and icosahedral symmetries is examined, using a simple pictorial model. It is shown that octahedral and icosahedral groups have a tetrahedral subgroup in common; in the full groups, this is the group Th, or, using just the rotation groups, the group T. In the analysis, various points emerge that may be of wider use in the teaching of symmetry. The misassignment of icosahedral symmetry as “cubic” is traced to a significant article in virology, whose authority has been great enough to allow the error to spread widely, and the nature of this mistake is analyzed. Reasons to maintain the conventional separation of cubic and icosahedral groups are given. Description: PUBLISHED 2010-01-01T00:00:00Z http://hdl.handle.net/2262/64079 Title: Quaternarized pdppz: Synthesis, DNA-binding and biological studies of a novel dppz derivative that causes cellular death upon light irradiation Author: WILLIAMS, DAVID CLIVE; GUNNLAUGSSON, THORFINNUR; ELMES, ROBERT Abstract: The quaternarized pdppz derivative 1 was shown to bind strongly to DNA with concomitant changes in its ground and excited state photophysical properties. Furthermore, the compound also showed rapid cellular uptake, and induced apoptosis upon light irradiation in various cancer cell lines after 24 hours of incubation. Description: PUBLISHED 2011-01-01T00:00:00Z http://hdl.handle.net/2262/64068 Title: Lanthanide directed self-assembly formations of Tb(iii) and Eu(iii) luminescent complexes from tryptophan based pyridyl amide ligands Author: GUNNLAUGSSON, THORFINNUR; MC CABE, THOMAS Abstract: The formation of self-assembly complexes between the ligands 1 (SS) and 2 (RR) and terbium or europium was undertaken and shown (using various spectroscopic titrations) to give rise to the exclusive formation of 2 : 1 (L : Ln) stoichiometry and not the anticipated 3 : 1 stoichiometry. Description: PUBLISHED 2011-01-01T00:00:00Z http://hdl.handle.net/2262/64067 Title: Sensing of biologically relevant d-metal ions using a Eu(iii)-cyclen based luminescent displacement assay in aqueous pH 7.4 buffered solution Author: GUNNLAUGSSON, THORFINNUR; Kotova, Oxana; Comby, Steve Abstract: 1 Eu BPS was developed as a luminescent lanthanide sensor for use in displacement assays for detection of d-metal ions by monitoring the changes in the europium emission, which was quenched for iron(II), with a detection limit of B10 pM (0.002 lg L 1) for Fe(II) in buffered pH 7.4 solution. Description: PUBLISHED 2011-01-01T00:00:00Z http://hdl.handle.net/2262/64064 Title: Structural Modifications of Ionic Liquid Surfactants for improving the Capability to Disperse Single-Walled Carbon Nanotubes in Water: an Experimental and Theoretical Study Author: GIORDANI, SILVIA Abstract: The 1-hexadecyl-3-vinylimidazolium bromide (hvimBr), a water-soluble long-chain imidazolium ionic liquid (IL) with surfactant properties, showed the ability to produce stable homogeneous aqueous dispersions of pristine Single-Walled Carbon Nanotubes (SWNTs). The purpose of this study is the improvement of SWNT dispersing ability by assessing the effect of different groups in position 3 of the imidazole ring. In this regard structural analogues were synthesized and, after characterization, their capability to dissolve SWNTs in water was investigated. Molecular Dynamics (MD) simulations have been performed to provide a semi-quantitative indication of the affinity of each dispersing agent toward SWNT and to attempt an explanation of the experimental results. Description: PUBLISHED 2011-01-01T00:00:00Z http://hdl.handle.net/2262/64041 Title: An intermembrane ion trap Author: MORTON-BLAKE, TONY; Bede, Peter; Bokde, Arun Lawrence Warren; Byrne, Susan; Hardiman, Orla Abstract: Molecular ion channels consisting of covalently stacked crown ether (CE) rings are mounted in a membrane bilayer between two ion-containing aqueous layers. Molecular dynamics shows that due to a large negative electrostatic potential on the axis of the channel, the cations (but not anions) in the electrolyte layers enter the channel. Calculations suggest that the cations encounter an energy barrier at the mouth of the channel and occupy axial sites between which they may undergo a dynamic redistribution. The application of electric fields sweep the ions to one end of the channel but fields of electrolytic strengths effect neither the exit of the cations nor the admission of anions. The retention of the ions M+ show that the CE channel acts as a trap for cations from the electrolyte layers. Description: PUBLISHED 2012-01-01T00:00:00Z http://hdl.handle.net/2262/63905 Title: Surface-Enhanced Raman Scattering from small numbers of purified and oxidised single-walled carbon nanotubes Author: GIORDANI, SILVIA; KOPF, ILONA Abstract: Temporal fluctuations of surface-enhanced Raman scattering spectra of purified and oxidised single walled carbon nanotubes have been observed. SERRS spectra were recorded that possessed fluctuating spectral profiles, these profiles possessed randomly fluctuation peak intensities and positions. Observation of bands in the 1000 to 1200 cm-1 frequency window was observed. A series of peaks in this window were observed to coincide with peak positions that have been assigned to arise from Stone-Thrower-Wales and heptagonal-pentagonal intramolecular junction defects on the nanotubes surface. We find that these peaks also occur for chemically treated SWCNTS. Description: PUBLISHED; (IF=2.3) 2012-01-01T00:00:00Z http://hdl.handle.net/2262/63763 Title: Redox switching and oxygen evolution at hydrous oxyhydroxide modified nickel electrodes in aqueous alkaline solution: effect of hydrous oxide thickness and base concentration Author: LYONS, MICHAEL EDWARD; Russell, Lisa; O'Brien, Maria; Doyle, Richard L; Godwin, Ian; Brandon, Michael P Abstract: Outstanding issues regarding the film formation, the redox switching reaction and the oxygen evolution reaction (OER) electrocatalytic behaviour of multi-cycled nickel oxy-hydroxide films in aqueous alkaline solution have been discussed. The oxide is grown using a repetitive potential multi-cycling technique, and the mechanism of the latter hydrous oxide formation process has been discussed. A duplex layer model of the oxide/solution interphase region is proposed. The acid/base behaviour of the hydrous oxide and the microdispersed nature of the latter material has been emphasized. The hydrous oxide is considered as a porous assembly of interlinked octahedrally coordinated anionic metal oxyhydroxide surfaquo complexes which form an open network structure. The latter contains considerable quantities of water molecules which facilitate hydroxide ion discharge at the metal site during active oxygen evolution, and also charge compensating cations. The dynamics of redox switching has been quantified in terms of a diffusive frequency via analysis of the cyclic voltammetry response as a function of potential sweep rate using the Laviron-Aoki electron hopping diffusion model by analogy with redox polymer modified electrodes. Potential step chronoamperometry applied to hydrous oxide coated Ni surfaces has indicated that the Ni(II)/Ni(III) redox switching reaction is quite complex. Steady state Tafel plot analysis has been used to elucidate the kinetics and mechanism of oxygen evolution. Tafel slope values of ca. 60 mVdec-1 and ca. 120 mVdec-1 are found at low and high overpotentials respectively, whereas the reaction order with respect to hydroxide ion activity remains invariant at ca. 1.0 as the potential is increased. These observations are rationalized in terms of a kinetic scheme involving Langmuir adsorption and the formation of a physisorbed hydrogen peroxide intermediate on the oxide surface. The dual Tafel slope behaviour is ascribed to the changeover in rate determining step from the second chemical hydroxide ion reorganization step to the first initial discharge step as the potential is increased, which is in contrast to the potential dependence of the surface coverage of adsorbed intermediates which holds for hydrous iron oxide electrodes in base. Description: PUBLISHED 2012-04-03T23:00:00Z http://hdl.handle.net/2262/63760 Title: Fluorous Catalyst Recycling Utilising Highly Fluorinated Zinc Compounds: Ring Opening Polymerisation of e-Caprolactone Author: BAKER, ROBERT JAMES Abstract: The synthesis of highly fluorinated zinc carboxylates, [{CF3(CF2)5CH2CH2CO2}2Zn], and alkoxides, [{CF3(CF2)5CH2CH2O}2Zn(OEt2)2] and their use as catalysts for the ring opening polymerisation of ɛ-caprolactone are described. Quenching the polymerisation reaction with fluorous acids or alcohols regenerates the catalyst which can be recovered by fluorous solvent extractions and the catalytic activity is retained for three cycles. The superior recyclability of the alkoxide to the carboxylate zinc compound is due to the greater partition coefficient between fluorous and organic solvents. Also investigated is the well defined aryloxide compound [(ArO)2Zn(THF)2] which yields very well controlled polymerisation, but cannot be recycled by quenching with a fluorous alcohol. Description: PUBLISHED 2012-01-01T00:00:00Z