This dissertation focusses on some advancements in methodology for measuring and analysing dissolved organic carbon (DOC): analysing data from a high resolution sensor generating DOC concentrations, [DOC] and secondly the use of Raman spectroscopy to analyse the composition of DOC. Recent advances in sensor technology have enabled the collection of DOC data with greater frequency over extended time periods than was previously possible through manually collecting water samples. In this research a time series of 30 minute [DOC] data for 2.5 years from Drumtee water, a peaty catchment in Scotland, was generated and analysed using a Spectro::lyserTM from S::CanTM, with a customised algorithm for calculating [DOC]. The time series revealed details of events and strong seasonal variation in the [DOC], with a range of 8.0 mg/l to 55.7 mg/l. During the same time period measurements made using manual sampling of river water were very similar, ranging from 10.2 mg/l to 81.1 mg/l (with the second largest value at 64.1 mg/l). Similar DOC export budgets were calculated from Spectro::lyserTM measurements and from the laboratory-analysed samples for both the hydrological year 2012/13 (HY 2012/13) and hydrological year 2013/14 (HY 2013/14). For the HY 2012/13 year the DOC budgets using the field collected data and the laboratory collected data were 16.6 gCm2.yr-1 and 19.8 gCm2.yr-1 respectively. For the HY 2013/14 year the DOC budgets using the field collected data and the laboratory collected data were 18.1 gCm2.yr-1 and 19.5 gCm2.yr-1 respectively. The similarity between the budgets calculated using the high-resolution [DOC] sensor and the budget calculated using laboratory measured [DOC] samples indicated that seasonal variation had a greater influence on export budgets than short term events had. GAMs were used to model the high resolution [DOC] data, and the model generated an R2 value of 0.75 and a p-value of < 2.2 x 10-16. It was also identified statistically that there were regular [DOC] dilutions during events and that these dilutions tended to coincide with the time period when discharge was increasing most rapidly. To identify relationships and periodicities in the high resolution [DOC] time series that would otherwise be challenging to identify three forms of wavelet analysis were used. These were continuous wavelet transforms (CWTs), maximal overlap discrete wavelet transforms (MODWTs) and wavelet coherence transforms (WTCs). Using the WTCs, it was determined that there were short term correlations between the [DOC] and pH between 25 June 2013 and 17 July 2013, between [DOC] and SC during 7 August 2013 and 7 October 2013 and between [DOC] and water temperature during 19 June 2013 and 30 June 2013. Although the although the relationship between [DOC] and temperature is strong over a full year it was over these shorter time periods the weakest of the three relationships established. Identifying this coherence was not possible using bivariate analysis and the long periods of no coherence obscured these responses when analysing the data on scatter plots. Although wavelet analysis has been used in other applications this is one of the first instances in which this technique has been applied to [DOC] time series. Raman spectroscopy, conducted using a 785 nm laser, was explored as an analytical tool that could enable a better understanding of DOC composition, as an alternative to the use of fluorescence spectroscopy. Tests were conducted using both Stokes and anti-Stokes Raman spectroscopy measurements with the best results obtained using anti-Stokes Raman spectroscopy. Solid phase measurements were made of glucose, fructose, sucrose, glycine, tyrosine, tryptophan and phenylalanine, but only the glucose produced a measurable spectrum of these substances. Measurements (powders and solutions) were made of humic and fulvic acids and these produced spectra that were measurably different from the background signals. The limit of detection was measured to be approximately 500 mg/l for both the humic acid and fulvic acid. It was identified that comparing the sections of the measured spectra between wavenumbers -1100 cm-1 to -1400 cm-1 to -1800 cm-1 to -2000 cm-1 could be used to differentiate between humic and fulvic acids. In summary, this research has focussed on the use of use high resolution sensor technology to generate and then analyse a long time series in a fluvial system with a particularly high [DOC], and made advances in being able to model the [DOC] using a GAM model, despite the complex relationship measured between discharge and [DOC]. Additionally, wavelet analysis has been applied to a [DOC] data set to identify trends in the [DOC] time series that would otherwise be hard to identify. Wavelet analysis has been applied to other geophysical time series such as those found in atmospheric research, but this appears to be the first time it has been applied to [DOC]. Additionally, the use of the anti-Stokes region of the Raman spectra has allowed identification of humic and fulvic acids, and established a limit of detection. Furthermore, an absorbance ratio was identified that can be used to determine whether a solution of humic substances is dominated primarily by humic acid or fulvic acid. This research appears to be the first study to explore this.

This thesis focusses on two areas. The first is elucidating the ultrafast photoprotective mechanisms exhibited by a number of commercial and natural sunscreening agents, through the use of femtosecond pump-probe transient absorption spectroscopy, coupled with ab initio electronic structure calculations. The second is understanding the electronic energy transport properties of pigment-protein complexes found in photosynthetic organisms, through the use of quantum dynamics simulations. Oxybenzone, titanium dioxide, octocrylene and ethylhexyl triazone are all studied given their prevalence in commercial sunscreen products. We deduce that oxybenzone relaxes through an enol-keto isomerism (~400 fs) followed by back-isomerisation commensurate with vibration energy transfer to the surrounding solvent (~5-8 ps). Titanium dioxide is then considered in multicomponent suspensions with oxybenzone, where we find that the photodynamics exhibited by each component can be considered independent from one another. Octocrylene is shown to undergo the majority of its photodynamics within ~2 ps, displaying remarkable efficiency as an ultraviolet light chromophore, relaxing through nonradiative internal conversion pathways. Studies of ethylhexyl triazone are presented, where results suggest this molecule relaxes through a number of ultrafast processes, ranging from ~400 fs, ~20 ps and ~200 ps, involving a large change in nuclear geometry, which couples excited states to the ground state through a conical intersection. Sinapoyl malate is the predominant sunscreening agent synthesised in arabidopsis thaliana which is deposited into the upper epidermis of its leaves. This molecule, along with its biological precursor sinapic acid, is shown to relax through ultrafast pathways (~10-30 ps), which we suggest is mediated by a trans-cis isomerism, in stark contrast to the recent time-resolved gas-phase measurements indicating the solvent environment alters the photodynamics significantly. Considering the second half of this thesis, we study the Fenna-Matthews-Olson pigment-protein complex found in green sulphur bacteria, and the light-harvesting complex II found in the spinach plant. Employing a simple quantum master equation, the Haken-Strobl model, we highlight a computationally tractable approach for describing these large, complicated systems. To this end, we perform an enormous array of simulations which include a simple description of environmental perturbations and find, for the first time, the full extent of the robustness of these pigment-protein complexes. Most strikingly, for the Fenna-Matthews-Olson complex, we find that up to 50% of the available pigments may be removed, with a small drop of 20% in electronic energy transport, displaying an incredible robustness to network disruption.

This thesis explores the potential of chiral plasmonic nanostructures for the ultrasensitive detection of protein structure. These nanostructures support the generation of fields with enhanced chirality relative to circularly polarised light and are an extremely incisive probe of protein structure. In chapter 4 we introduce a nanopatterned Au film (Templated Plasmonic Substrate, TPS) fabricated using a high through-put injection moulding technique which is a viable alternative to expensive lithographically fabricated nanostructures. The optical and chiroptical properties of TPS nanostructures are found to be highly dependent on the coupling between the electric and magnetic modes of the constituent solid and inverse structures. Significantly, refractive index based measurements of strongly coupled TPSs display a similar sensitivity to protein structure as previous lithographic nanostructures. We subsequently endeavour to improve the sensing properties of TPS nanostructures by developing a high through-put nanoscale chemical functionalisation technique. This process involves a chemical protection/deprotection strategy. The protection step generates a self-assembled monolayer (SAM) of a thermally responsive polymer on the TPS surface which inhibits protein binding. The deprotection step exploits the presence of nanolocalised thermal gradients in the water surrounding the TPS upon irradiation with an 8ns pulsed laser to modify the SAM conformation on surfaces with high net chirality. This allows binding of biomaterial in these regions and subsequently enhances the TPS sensitivity levels. In chapter 6 an alternative method for the detection of protein structure using TPS nanostructures is introduced. This technique relies on mediation of the electric/magnetic coupling in the TPS by the adsorbed protein. This phenomenon is probed through both linear reflectance and nonlinear second harmonic generation (SHG) measurements. Detection of protein structure using this method does not require the presence of fields of enhanced chirality whilst it is also sensitive to a larger array of secondary structure motifs than the measurements in chapters 4 and 5. Finally, a preliminary investigation into the detection of mesoscale biological structure is presented. Sensitivity to the mesoscale helical pitch of insulin amyloid fibrils is displayed through the asymmetry in the circular dichroism (CD) of lithographic gammadions of varying thickness upon adsorption of insulin amyloid fibril spherulites and fragmented fibrils. The proposed model for this sensitivity to the helical pitch relies on the vertical height of the nanostructures relative to this structural property as well as the binding orientation of the fibrils.

A combination of spectroscopic methods and symmetry considerations were used throughout the presented studies to investigate the terahertz spectra showing liquid dynamics in varied systems. Optical Kerr effect spectroscopy revealed clusters of different sizes in aqueous sodium thiosulfate solutions with non-Newtonian behaviour. In conjunction with terahertz infrared spectroscopy, optical Kerr effect spectroscopy showed the charge-ordered nature of butylammonium ionic liquids, which manifested through phonon modes in the terahertz spectra. In eutectic lithium thiocyanate solutions, a combination of mid-infrared spectroscopy, optical Kerr effect spectroscopy and X-ray scattering showed a separation into nanoscale water-rich and salt-rich domains at low temperatures. In summary, the use of terahertz spectroscopy on selected model system provides information on the dynamics governing the behaviour of liquids and solutions.

Nanoparticles of many varieties are increasingly studied for use in the physical, chemical, and biological sciences. Metallic nanoparticles exhibit morphology-dependent localised surface plasmon resonances (LSPR), which couple to propagating light, and manifest as a resonant particle polarisability at the LSPR frequency. These resonances can be harnessed for a variety of applications. Many of these applications require characterisation of NP properties, such as their optical response, summarised by the ab- sorption and scattering cross sections. Quantitative measurement of individual NPs is technically difficult, and ensemble measurement techniques, such as absorption spectroscopy, are frequently employed. However, individual NP properties can vary significantly, within the ensemble. In this work, we present a novel, and easy to implement, wide-field extinction microscopy technique, capable of analysing hundreds of nanoparticles simultaneously. Using this technique, we are able to characterise individual gold nanoparticles down to 5 nm diameter, and collate the data to produce ensemble statistics. Furthermore, we developed a program for the rapid analysis of the acquired image, enabling implementation by others in a cost-effective and efficient manner. Using the wide-field extinction technique, we have studied several sizes of gold, platinum, silver, and diamond nanoparticles. We used gold nanoparticles to pro- vide a proof of concept, and found good agreement with the literature. We also present an experimental investigation towards an in-vitro plasmon ruler. Coupled metallic NPs exhibit a LSPR, which is dependent on interparticle distance. The four-wave mixing technique we employ is phase-sensitive, allowing measurement of the shift of the res- onance frequency of gold NPs. To provide proof-of-principle of the plasmon ruler, we correlatively studied gold nanoparticle dimers, with transmission electron microscopy, and four-wave mixing microscopy. In this way, we obtained a direct measure of the interparticle distance, and could relate it to the measured phase shift in four-wave mixing.

Photosynthetic organisms harvest sunlight through antenna light-harvesting complexes. Light absorbed by chromophores is transferred down an energy gradient to a reaction centre (RC) where photoinduced electron transfer occurs. A charge-separated state is generated that preserves some of the original light energy as electrochemical potential. By studying these RCs allows for us to deduce how they function through the elucidation of their structure, which ultimately allows for artificial mimics to be made. Chlorobaculum tepidum (C. tepidum) is a green sulphur photosynthetic bacterium that contains a type I RC. Light energy is transferred to the RC from chlorosomes via a soluble Fenna-Mathews-Olson (FMO) protein. Although the structure of FMO has been solved on its own, little is known about the molecular organization of the reaction centre complex. This thesis looks at two of the RC sub-units (PscB and PscD) that are water-soluble. To understand the contribution that these proteins make to RC function, they have been made in E. coli using an in-house expression vector. Using a 3C protease - iLOV - biotin acceptor domain - His10 (CLBH) tag, both PscB and PscD can be readily purified on a milligram-scale in four simple steps (Ni2+-affinity, subtractive IMAC (immobilized metal affinity chromatography) after cleavage with 3C protease, gel-filtration). PscD and PscB have been labelled with 15N and 13C for structural analysis by NMR, so far PscD has shown to partially disordered implying that a potential binding partner may be required. PscB has shown to be well structured and is in the process of having its structure elucidated. The binding PscD with FMO and ferredoxin from Arabadopsis thaliana has also been assessed by isothermal calorimetry to help identify the function of this protein. Here it is also observed that when the RC is coupled to plasmons a near 5 fold increase is observed in fluorescence enhancement as compared to RC by itself. Plasmonic metallic nanoparticles are able to drastically alter the emission of vicinal fluorophores. Metallic nanoparticles can influence the fluorescence emission of nearby molecules by enhancing the absorbance of the molecule, and by modifying the radiative decay rate of that molecule. And this is what is observed. This can further be increased when coupling the RC to the Plasmon by placing a silicon dioxide (SiO2) spacer in-between the RC and nanoparticle. This is the highest flouresence enhancement observed to date. As yet, no green sulphur bacterial RC has had its structure determined. Here, purification protocols have been developed that allow milligram quantities of a complex between the RC and FMO to be prepared. As well as identifying the best suitable detergents for solubilising and purifying the RC, two different populations of the RC have been discovered that can be separated by sucrose density gradients. Vapor diffusion, lipidic-cubic phase (LCP), bicelle, and co-crystallisation trials have been performed with pure RC-FMO. Thus far, promising crystals have been obtained when the RC has been co-crystallised with ferredoxin to 60 Å. These promising crystals are the first of its type, as this is the first type 1 RC crystal obtained.

A substantial amount of research has already been undertaken towards creating commercially viable organic photovoltaics (OPVs). This is due to the potential use of OPV cells as an inexpensive source of renewable energy. There are many factors to consider in OPV cell design, including photo-active materials, cell architecture and electrode selection. However, additional interlayers for use between the photo-active materials and the electrodes were identified to be as important and need to be developed to optimise cell performance. The work presented here focuses on the influence of various metal oxide hole extracting layers in different OPV systems. Metal oxides such as molybdenum oxide (MoOx) have shown great promise in polymer cells as a hole extracting layer, and here we investigate their use in small molecule cells. An optimised MoOx layer thickness of 5 nm provides a ~ 60 % increase in overall power conversion efficiency (ηp) for chloroaluminium phthalocyanine (ClAlPc) / fullerene (C60) cells in comparison to those fabricated on bare ITO. A similar improvement of ηp is reported when using the MoOx layer in a boron subphthalocyanine chloride (SubPc) / C60 system. For both high ionisation potential donor materials, the cells containing MoOx achieve a significantly higher open circuit voltage (Voc). Conversely, cells utilising the lower ionisation potential donor materials such as copper phthalocyanine (CuPc) and pentacene produce similar Voc values when deposited on both ITO and MoOx. Hence, the ηp is marginally reduced with the MoOx layer. To attain a deeper understanding, the factors behind these performance differences were explored by UV-vis absorption spectroscopy, ultra-violet photoemission spectroscopy (UPS), X-ray diffraction (XRD) and atomic force microscopy (AFM). Thermally evaporated vanadium oxide (V2Ox) was used as an alternative hole extracting layer to MoOx, achieving analogous performance to MoOx when used in SubPc / C60 and CuPc / C60 cells. The electronic properties of the V2Ox layer are investigated using UPS, and it is demonstrated to have substoichiometric n-type character in contrast to the p-type behaviour previously reported. Additionally, the in-situ fabrication and characterisation of organic layers using UPS indicate Fermi level pinning of the organic to the metal oxide. A solution processed vanadium oxide (V2Ox(sol)) layer was developed and characterised as an alternative method of layer fabrication. The atmospheric processing conditions are found to have a dramatic effect on cell performance, and are studied using x-ray photoelectron spectroscopy (XPS). Layers spin-coated under a nitrogen atmosphere exhibit a larger composition of V4+ states. Kelvin probe and UPS experiments indicate the V2Ox(sol) is also a high work function, n-type layer, with the V2Ox(sol) hole extracting layer producing similar cell performance to the thermally evaporated metal oxide layers. Cells deposited on the V2Ox(sol) layer demonstrate good operational stability characteristics, outperforming a commonly used solution processable hole extracting layer.

This thesis is concerned with the study of biophysicochemical processes using electrochemistry and related techniques. The first part of the thesis discusses the electrochemical detection of biological species, and characterisation of the electrode materials employed. A comparison of two novel forms of carbon electrode, namely carbon nanotubes and polycrystalline boron doped diamond (pBDD), with more conventional carbon electrode materials reveals their enhanced characteristics for bioelectrochemistry, with improved sensitivity and resistance to fouling. These materials are further characterised using novel high-resolution electrochemical imaging methods, to determine heterogeneous electron transfer rates for a number of different redox species. The kinetic rate constants are determined from measured electrochemical currents using finite element method (FEM) modelling, which proves to be a powerful technique for the quantitative analysis of intrinsic system parameters that cannot be studied directly. The electrochemical response of isolated regions of pristine SWNTs is investigated using scanning electrochemical cell microscopy, demonstrating high electrochemical activity at the nanotube sidewalls. A similar analysis of the different facets of pBDD is performed using intermittent contact scanning electrochemical microscopy coupled with FEM simulations, revealing that the electroactivity is strongly in uenced by the local density of states of the material. New techniques are also presented for the investigation of transport processes at membrane interfaces. A new method of bilayer formation is developed, which overcomes many of the limitations of current techniques, and is used to investigate the permeation rates of a series of aliphatic carboxylic acids. Using confocal laser scanning microscopy (CLSM) with a pH-sensitive uorophore, the pH change as a weak acid permeates across the bilayer can be visualised, and the permeation coefficient determined by comparison with FEM simulations. This reveals a trend of increasing permeability with lipophilicity. Finally, CLSM is used to study the lateral diffusion of protons at lipid bilayers and other surfaces. Protons are generated galvanostatically by a UME positioned close to the substrate, altering the local pH which can be visualised by means of a pH-sensitive uorophore. The uorescence profile is again compared to FEM simulations, allowing the lateral diffusion coefficient to be determined.

This thesis discusses the synthesis of transition metal chalcogenide nanostructures (where the chalcogen is either sulfur, selenium or tellurium) through the use of standard chemical vapour transport (CVT) and chemical vapour deposition (CVD) techniques. The resultant structures are characterised with a variety of methods and comparisons of their properties are made with their bulk counterparts. A discussion into how some of these structures form during the reaction is also given. Highly symmetrical, isotropic, nickel disulfide (NiS2) nanocubes have been synthesised via a Physical Vapour Transport (PVT) method in which sulfur vapour generated in situ is reacted with nickel-coated silica substrates. Systematic studies demonstrate the effect of the reactant ratio, substrate, metal layer thickness and reaction temperature on the synthesis and growth process. The evolution of structure and composition has been followed by diffraction and scanning electron microscopy (SEM). The size of the NiS2 cubes can be varied from below 200 nm to 1 -2 1m across. Magnetic properties of the disulfide nanomaterials have been determined using superconducting quantum interference device (SQUID) magnetometry. Initial experiments also demonstrate that related CVT techniques can be exploited to produce alternative compositions in the Ni-S system with varying morphologies that can be controlled via chemical and physical reaction parameters. Surface Assisted Chemical Vapour Transport (SACVT) methods have been employed to grow flower-like nanostructures of titanium disulfide (TiS2) and titanium trisulfide (TiS3) on titanium coated silica substrates. Systematic studies demonstrate the role of the reactant ratio and reaction temperature on the synthesis and growth process. The evolution of structure and composition has been followed by powder X-ray diffraction (PXD) and electron microscopy techniques such as and transmission electron microscopy (TEM). Magnetic properties of the disulfide nanomaterials have been determined using SQUID and Raman spectroscopy has been used to confirm the identity of the sulfides. Investigations into nanostructured materials of the group IV transition metals zirconium and hafnium resulted in the successful synthesis of nanostructures of zirconium trisulfide/selenide (ZrS3/Se3) and hafnium trisulfide/selenide (HfS3/Se3). The unusual effects on structure that can occur when reactant time and synthesis temperature are varied and when a balance between these two factors is successfully found, nanostructures other than tubes and wires can be formed. Each of these systems were characterised with a variety of techniques including, TEM, PXD and SQUID.

Due to intrinsic limitations of conventional silicon based devices the trend of miniaturisation cannot continue indefinitely, thus molecular devices are being used to develop smaller, faster and higher storage density memory devices. We present a thermally activated, switchable hetero-polyoxometalate (HPOM) cluster immobilised on a highly polarisable gold surface which has potential as such a device. This cluster consists of a nanometre sized Mo(IV) oxide “shell” which encapsulates two electronically active pyramidal sulfite (SIVO32-) groups, and has the ability to reversibly interconvert between two electronic states. In the passive state, at cryogenic temperatures (77 K), the two SO32- groups are non-bonding with respect to the sulfur centres, however upon thermal activation, i.e. when the temperature is increased to room (298 K), two electrons are ejected from the active sulfite anions and delocalised over the metal oxide cluster cage. This has the effect of switching it from a fully oxidised to a two-electron reduced state, along with the concomitant formation of an S-S bonding interaction between the two sulfur centres inside the cluster shell. This process does not occur in the crystalline state and to proceed requires the stabilising effects provided by an image charge, generated as a consequence of being adsorbed onto a metal surface. The prototypical enantio-selective heterogeneously catalysed reaction involves the hydrogenation of the α-ketoester, methyl pyruvate on Pt. Using TPD, XPS and UPS we have investigated this compound’s behaviour on a model Cu(111) single crystal surface. Monolayers of methyl pyruvate at 180 K consist predominately (ca. 66%) of a chemisorbed methyl pyruvate moiety, with its keto-carbonyl bonded to the surface in a η2configuration, this moiety desorbs intact at 364 K. The rest of the monolayer contains weakly adsorbed methyl pyruvate, which desorbs at 234 K, and interacts with the surface through the lone pair electrons of the oxygen atoms of the C=O groups, adopting a η1 configuration. The observation of a strongly chemisorbed moiety in the present study is attributed to the activation of the keto-carbonyl by the electron withdrawing ester group, and is consistent with the homogeneous inorganic chemistry of ketones. It is widely assumed that the α-ketoester needs to be π-bonded to the surface for the enantio-selective hydrogenation to proceed, consequently, given both the formation of a η2 bonded methyl pyruvate moiety on Cu(l11) and the known activity of Cu as a selective hydrogenation catalyst, it is suggested that it is maybe worthwhile considering the possibility of testing the effectiveness of chirally modified supported Cu as an enantio-selective catalyst. The thermal and electron induced chemistry of (S)- and (R)-methyl lactate (MLac) on Cu(111) was investigated; both enantiomers exhibited similar behaviour. MLac adopts one of two adsorption modes on the terraces of a Cu(111) crystal, which desorb molecularly at 209 K and 220 K. Concerning the molecules adsorbed at defect sites, as the temperature is increased over the range 250 – 300 K, a fraction desorb intact, while the majority lose a hydrogen atom to form the more strongly bound alkoxy species on the surface. Of these, some recombine with the hydrogen and proceed to desorb as MLac at 360 K, while a larger proportion are dehydrogenated further and methyl pyruvate and hydrogen are ejected from the surface at 380 K. When a monolayer of MLac is irradiated with a low energy electron beam, the molecules at the terrace sites are electronically excited and desorb as intact molecules, while those at the defect sites undergo electron induced hydroxyl O-H bond cleavage. Subsequent to electron bombardment there is consequently a decrease in molecularly adsorbed MLac and an increase in the number of strongly bound alkoxy species on the surface, entities which are not susceptible to ESD. We believe the ESD excitation mechanism is dissociative electron attachment. Low energy electrons of <1 eV are prevalent in the secondary electron background and can excite the hydroxyl O-H stretch, facilitating its cleavage at a threshold of 1.4 + 0.7 eV. The cross sections for the electron induced processes are high, 3.0 + 0.4 x 10-16 cm2 for 50 eV electrons, thus MLac is extremely susceptible to electron stimulated desorption. The enantio-specific adsorption of both the (S)- and (R)- enantiomers of methyl lactate on the chiral Cu(643)R surface has been investigated. The results from the (111) surface enabled us to assign the features in the TPD profiles. The peaks arising from molecular desorption at terrace and step sites occurred at the same temperature for both enantiomers, however, those attributed to desorption from the kink sites differed by 13 K, representing an enantio-specific difference in desorption energies of 0.94 kcal mol-1. This value is significantly larger than those observed in previous experimental work, although it is consistent with theoretical studies. Furthermore, we also observed enantio-specific surface reactions. It was found that there was a greater tendency for the (R)- enantiomer to undergo both the alkoxide recombination reaction and further dehydrogenation to methyl pyruvate, while the (S)-enantiomer had a greater proclivity to undergo total decomposition. We have discovered, to the best of our knowledge, the first example of enantio-specific surface chemistry initiated by a beam of non-chiral low energy electrons. When (S)- and (R)-methyl lactate molecularly adsorbed at the chiral kink sites of a Cu(643)R substrate is irradiated with 50 eV electrons, it has been found that (R)-methyl lactate is more receptive to both electron induced desorption of the parent molecule and electron induced cleavage of the hydroxyl O-H bond. This behaviour has been attributed to the (S)-enantiomer forming a more intimate bond with the kink site than the (R)-enantiomer, as evidenced by its higher desorption temperature. Consequently the substrate is more effective at providing relaxation channels to the electronically excited adsorbate, which reduces the probability of ESD occurring. Starting with a racemic mixture, we have demonstrated a 20% enantiomeric enrichment in the molecular adsorbates at the chiral kink sites, after only 30% depletion of the initial population. As a control, the initial rates of desorption from terrace and step sites were found to be unaffected by enantiomeric identity, which was to be expected because these sites are achiral, and as such both enantiomers interact to a similar degree with each. When the monolayer is considered as a whole, it was found that electron irradiation drives desorption more completely with an (R)-MLac covered surface than with (S). It has been suggested that this property of the system could be exploited in the laboratory as a method for separating racemic mixtures, and that in an astrochemical context, it could provide insight into the origins of biohomochirality.