cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1720214
title: Equation of state and phase transitions of the cubic NTE material Cd(CN)2

description: Despite being the material showing the largest isotropic NTE, Cd(CN)2 is remarkably little studied, particularly compared to isostructural Zn(CN)2 and the canonical NTE material ZrW2O8, as such this is an exciting opportunity to study this system using neutrons. This study aims to carry out a comprehensive and long-needed variable-p,T structural study of 112Cd(CN)2, with a number of important objectives: (i) to determine the nature of its structurally complex low-temperature phase(s) (T &lt; 150 K); (ii) to determine the equation of state, including the ambient-temperature bulk modulus and the temperature-dependence of the bulk modulus; (iii) to identify and characterise structurally the high-pressure phase(s); and (iv) to exploit the resolution and d-spacing coverage offered by HRPD to characterise properly the p,T-dependent changes in Cd(CN)2.
DOI: 10.5286/isis.e.rb1720416
title: Total scattering structures of non-graphitisable carbons for applications in sodium-ion batteries

description: Due to the high global abundance of sodium, Na-ion batteries are an attractive option to Li-ion batteries for low-cost energy-storage technologies. Graphite, the anode choice in Li-ion batteries, cannot intercalate Na electrochemically. On the other hand, non-graphitisable carbons have shown good reversible capacities and life cycle when used as negative anodes in Na-ion batteries. In order to elucidate the structural features of carbon anodes for Na-ion batteries, we propose to perform neutron total scattering studies on a series of non-graphitisable carbons to understand and correlate the findings with the Na storage mechanism measured ex situ. The fundamental understanding resulting from our studies will clearly facilitate the future production of optimised carbon anodes for Na-ion batteries to facilitate their future commercialisation.
DOI: 10.5286/isis.e.rb1510165
title: Oxygen-deficient quantum spin ice

description: In quantum analogues of the spin ice materials quantum mechanical tunneling between ground states is expected, and exotic emergent behaviour has been predicted including a Higgs transition to a ferromagnetic phase, and an emergent electrodynamics that, in addition to gapped electric and magnetic charges, hosts gapless photon excitations. However, the ground states of the potential experimental realizations of these systems are strongly sample dependent, suggesting a key role for defects. In our previous work we showed that oxygen deficiency is the dominant contribution to defects in classical spin ice materials, and that this leads to magnetic distortions that slow down the long-time monopole dynamics at sub-Kelvin temperatures. We now propose to employ the techniques successfully used to study defects in classical spin ices to the quantum spin ices.
DOI: 10.5286/isis.e.rb1510181
title: A unique borohydride bridged dimer of Ni(I)

description: The reaction of Ni(6-Mes)(PPh3)Br (6-Mes = bis(1,3-(2,4,6-trimethylphenyl)imidazol-2-ylidene) with 2.5 equivalents of NaBH4 leads to formation of product characterised as {Ni(6-Mes)}2(mu-BH4)2 (2, Scheme 1).The product has been characterised by X-ray crystallography, but we were unable to elucidate the precise coordination modes of the two asymmetrically bound bridging borohydride ligands. Such information is vital in rationalising the likelihood of BH3 loss as a route to what would be a unique and possibly catalytically active Ni(I)-H species.
DOI: 10.5286/isis.e.rb1510235
title: A pair distribution function study of the thermoelectric skutterudites Co1-2xFexNixSb3 (0 &lt;= x &lt;= 0.5)

description: Sustainable energy-conversion technologies are important for ensuring our energy supply against declining fossil fuel reserves. Thermoelectric materials offer great potential for the conversion of waste heat energy into useful electrical energy. As part of a collaborative research program, which seeks to implement thermoelectric energy recovery in automotive exhaust systems, we are investigating the structure and properties of skutterudites, which are materials with attractive thermoelectric properties. In the course of this work, we have discovered that isoelectronic substitution of Co with a 50:50 mixture of Fe and Ni in the CoSb3 skutterudite results in a marked reduction in the thermal conductivity. The origin of this effect is not clear, and here we seek to exploit pair distribution function analysis to investigate the effect of the local environment in the thermal conductivity
DOI: 10.5286/isis.e.rb1510405
title: The Structural Effects of adding TiO2 to Calcium Phosphate Glasses.

description: This study will investigate the structural effect of adding titanium oxide to a calcium phosphate bioactive glass.  We wish to understand the structural origins of the increased durability the addition of TiO2 gives to these glasses so the the dissolution rate of the glasses can be more carefully controlled through compositional development.  We will use the P2O5-MgO-CaO-Na2O glass system and substitute TiO2 in for both the network former (P2O5) and the network modifiers to gain a comprehensive understanding of the structure of these glasses.
DOI: 10.5286/isis.e.rb1510565
title: Probing diffusion of renewable feedstocks in single-site nanoporous materials

description: Silicon-doped aluminophosphates (SAPOs) are framework materials similar to zeolites. Their pore structure and solid acid sites contribute to their activity and selectivity in the upgrading of petrochemicals. Recent work has suggested that an undesirable side reaction which forms ethylene rather than diethyl ether in ethanol conversion may depend on selectivity of the SAPO framework. The ethylene forms by decomposition of the ether product and is likely to relate to diffusion processes. If the ether product does not freely diffuse out of the pores after formation, it will be in proximity to active sites and liable to decomposition. Measuring diffusion rates of chemicals involved in this reaction is therefore of interest to understand this reaction and inform future SAPO catalyst design.
DOI: 10.5286/isis.e.rb1510601
title: A new plastic phase in PCBM from low-energy inlelastic neutron scattering

description: Phenyl-C61-butyric acid methyl ester (PCBM) is a fullerene-based material of high technological interest due to its use in organic solar photovoltaic cells. A better understanding of its thermal properties is needed to provide fresh insights into the prospects of higher energy-conversion efficiencies for this family of organic materials. Following a successful Xpress run on IRIS, this proposal seeks to provide an unambiguous identification and detailed characterisation of a plastic/rotor phase in PCBM above 360K, analogous to that which is found in C60. In conjunction with ongoing molecular-dynamics simulations, these experimental data will also be used to understand PCBM's extremely low (and hitherto unexplained) thermal conductivity.
DOI: 10.5286/isis.e.rb1520076
title: Impact of Anion Ordering on Strains in Perovskite Oxynitrides

description: This proposal will study the temperature dependence of the structure of a novel perovskite oxynitride SrTaO2N in order to establish how anion ordering impacts on the coupling of the octahedral tilting and lattice distortion.   This is important since the important optical (band-gap) properties of perovskite oxynitrides are sensitive to small structural distortions.
DOI: 10.5286/isis.e.rb1520210
title: Suppression of thermal conductivity in nanostructured ZnO

description: Thermoelectricity offers solutions for the low-carbon economy through the development of energy-efficient technology. Modest improvement in thermoelectric performance would allow, for example, waste heat in car exhausts to be converted into useful power, and hot spots on computer chips to be cooled using solid state refrigerators. However, most thermoelectric materials have complicated structures with scarce or harmful elements. Zinc oxide and its alloys are attractive candidates because of their simplicity, high thermal stability, corrosion resistance, non-toxicity and low cost. The electronic transport of zinc oxide is ideal for thermoelectric applications, but its thermal conductivity is too high. However, nanostructuring reduces the thermal conductivity by an order of magnitude. We aim to understand this phenomenon by measuring lattice vibrations using inelastic neutron scattering.
DOI: 10.5286/isis.e.rb1610183
title: Phase Separation in NaTaO3.  Can it be controlled by pressure?

description: The present proposal seeks to establish the pressure dependence of the Pbnm-Cmcm transition in NaTaO3 and some doped variants thereof.  It aims to understand the understand the non-perovskite-like peak splitting observed in HRPD data recorded for NaTaO3 at room temperature and the unusual stability of the Cmcm phase in this material.
DOI: 10.5286/isis.e.rb1610239
title: Determination of interfacial dead layers and magnetic uniformity in half-metallic full Heusler alloys

description: Co-based Heusler alloys are predicted to be an ideal material for spintronics due to their high Curie temperature and potential in magnetic heterostructrue devices. We have recently completed a PNR study of Co2FeAl0.5Si0.5 grown on Si(111), and found there to be reduced magnetic moment in the film (5.7uB) and a magnetic dead layer at the interface due to silicon diffusion from the substrate. We have now grown CoFeAl0.5Si0.5 on Ge(111) and intend to perform PNR to analyse the magnetic and structural profile of the samples. We expect to see enhanced magnetism in the film (6uB), and for the magnetic and structural profiles to be correlated due to the lack of silicon diffusion.
DOI: 10.5286/isis.e.rb1610336
title: Investigation of caprolactam-d11 at high pressure

description: High pressure has shown to be a powerful tool for the exploration of the organic solid state.  In particular one is able to perform polymerisation reactions on solid materials by the sole application 1000s atmospheres of pressure.  The fact that the material is solid means that the molecules to be polymerised are in a specific orientation with respect to one another which impacts on the structure of the polymer created.  We have recently investigated a number of systems under pressure and have found that they change their crystalline structureand they also undergo polymerisation reactions.  Caprolactam is an important monomer in polymer science and is the pre-cursor to Nylon-6.  We have investigated this system using our laboratory instruments and have found that above 2 GPa it undergoes a change. We seek to characterise these changes further using powder diffraction.
DOI: 10.5286/isis.e.rb1610386
title: The effect of pressure on the hydrogen bonding in ammonium formate

description: We propose to investigate the changes that occur in the structure of ammonium formate as a function of pressure.   This is the simplest system in which the oxygen atoms of a carboxylate group are hydrogen bonded to the hydrogen atoms of an NH group.  This compound is known to undergo a phase transition at 1.8 GPa, during which there is a significant reorganization of the hydrogen-bonding network. We will determine the evolution of the changes within the hydrogen bonds for both phases.   In particular the hydrogen bonding in the high pressure phase is such that for on the oxygen atoms the intermolecular bonding occurs within the plane of the carboxylate group whilst for the other oxygen it is at right angles to this plane.  This bonding arrangement gives us an opportunity to investigate the effect of pressure on a system where both in and out of plane hydrogen bonding occurs.
DOI: 10.5286/isis.e.rb1610415
title: In-situ Battery Discharge Studies of Thermal Batteries using Transition Metal Sulfides and Chlorides as Cathodes

description: Thermal batteries find use in applications such as emergency power systems and ejector seats in aircraft.  They operate at elevated temperatures of around 400-500 °C, where the halide salt electrolyte is molten.   There is considerable lack of detailed understanding of the structure-property relationships in these materials, due to the high temperature required and sealed battery cells involved in such measurements.   We are currently undertaking a project to understand how the chemical structure of the cathode materials changes on discharge of the battery.   Here, we aim to look at the in-situ battery discharge of three cathode materials, using a specialist rig which has been developed at St Andrews, to collect electrochemical and diffraction data simultaneously.
DOI: 10.5286/isis.e.rb1610425
title: Local and intermediate-range order in AgI-containing glasses

description: Usual structural hypothesis related to superionic glasses containing metal halides MY = LiI, NaBr, AgI, etc., implies the absence of chemical interactions between the host glass and metal halide.  An expansion of the host network caused by large anions (I, Br) and related increase of the available free volume for fast cations, forming preferential conduction pathways, was considered to be the key parameter for glassy superionics.  Our preliminary results for a (AgI)0.2(As2S3)0.8 glass show that this AgI-poor sample exhibits a mixed silver tetrahedral environment (2S+2I).  Consequently, a strong evidence of chemical interaction between AgI and As2S3 host glass is observed.  We are asking for 2 days on GEM or SANDALS to elucidate the short-range order and connectivity of the AgI-related subnetwork and follow the expected evolution from isolated to extended Ag-centred structures.
DOI: 10.5286/isis.e.rb1610441
title: Effect of structure on the location of hydrophobic drugs in ionic surfactant monolayers

description: Many drugs are both poorly water-soluble (hydrophobic) and lipophilic in nature and are therefore incorporated into surfactant micelles and monolayers. As the incorporation of drug into surfactant monolayers mirrors its distribution in surfactant micelles, the study of drug distribution into surfactant monolayers should provide useful information about the nature and extent of drug solubilisation. The present study aims to determine the amount incorporated and the extent of penetration of the hydrophobic drug testosterone enanthate into monolayers of dodecyltrimethylammonium bromide as well as the hydrophobic drugs, adrenosterone and 4-cholesten-3-one in monolayers formed by the surfactant, sodium dodecyl sulphate at the air/water surface. The study will provide invaluable information in understanding the location of the drugs in the surfactant micelles.
DOI: 10.5286/isis.e.rb1610512
title: Structural relaxation in liquid Gallium

description: Cooling down a liquid at ambient pressure all except Helium attain a solid state. If a crystalline state is reached a dramatic change in long range order occurs manifesting the first order phase transition. However, if crystallization can be avoided the liquid can be undercooled and eventually the material morphs into a glass. A lot of effort has been devoted to establish the changes in dynamics towards the glass transition in the past. Less simple to answer is the question at which temperature that slowing down sets in or whether such a temperature range exists at all. We observed in a few liquid metals changes in liquid dynamics which point to a universal behaviour. To put more weight on this conjecture we propose to investigate a metal with a rather different interaction potential, Gallium.
DOI: 10.5286/isis.e.rb1620066
title: The impact of aging on mixing at polymer/fullerene interfaces

description: Polymer/fullerene blends represent the most common form of organic solar cell.  This proposal forms part of a wider effort in which our motivation is to complement solar cell optimisation strategies, with in-depth studies aimed at increasing the fundamental understanding of the materials science within polymer/fullerene thin films. Long-term stability is a critical issue for the commercialisation of organic devices, and initial measurements suggest considerable sensitivity of the physical structure/morphology of films to aging processes. Our aim in this proposal is to understand how various aging processes can affect miscibility in polymer/fullerene thin-films, and to determine the origin of this sensitivity. We will investigate this by performing chemical and physical aging experiments, of direct relevance to device operating conditions, followed by specular reflectivity measurements.
DOI: 10.5286/isis.e.rb1620165
title: Study of interface and induced magnetic moment in C60 in bi- and tri-layers of Fe/C60 by polarized neutron reflectivity

description: Single layer of Fe, bi- and tri-layers of C60/Fe are grown on MgO (001) substrate using DC magnetron sputtering and thermal evaporation for Fe and C60, respectively. The samples exhibit both uniaxial and cubic anisotropies. Hysteresis loops and domain images measured by Kerr microscopy reveal strong effect of C60 on the magnetization reversal mechanism of Fe. Preliminary fits of polarized neutron reflectivity data for C60/Fe bilayer indicate spin polarized charge transfer at the interface by inducing magnetic moment of Fe in C60 upto a few monolayers. However, the quantification of the magnetic moment in C60 and the change in magnetization reversal process of the systems are yet to be explained.We would like to  i)quantify the transverse component in the system  ii)determine the induced magnetic moment in C60 at the interface between Fe and C60 layer.
DOI: 10.5286/isis.e.rb1620457
title: Investigating the superconducting and magnetic properties of new-structure-type Fe-Based Superconductors: CaAFe4As4 and SrAFe4As4

description: CaAFe4As4 (A = K, Rb, Cs) and SrAFe4As4 (A = Rb, Cs) are the brand new Fe-based superconductors, only reported in 2016 and is abbreviated as 1144 compounds. Tc values of these 1144 compounds vary from 31 to 36 K. So far there is only one published work on these new-found materials and very little information available about the superconducting and magnetic properties. µSR will be a very useful technique to explore it all. Here we propose to study the magnetic and superconducting properties of these 5 superconducting materials by a combination of zero-field and transverse-field µSR measurements. We ask for 10 days of MuSR beamtime to complete the proposed study.
DOI: 10.5286/isis.e.rb1700076
title: Cypress Semiconductor High-Energy Neutron Evaluation

description: 1) Neutron testing of NVM 65nm FL-L products.  These flash memories will be programmed and exposed to neutrons to count the number of bit flips.2) Neutron testing of NVM 65nm GL-S products.  This flash memory will be programmed and exposed to neutrons to count the number of bit flips.3) Neutron testing of NVM 45nm GL-T products.  This flash memory will be programmed and exposed to neutrons to count the number of bit flips and monitor for latching performance.4) Neutron testing on 40nm MicroController Traveo product.  The goal of this experiment will be to subject the programmed memory areas of the device (both flash and SRAM) and monitor for bit flips due to the neutron beam.  Current will also be monitored to look for latch-up.
DOI: 10.5286/isis.e.rb1710203
title: Paramagnons in the chiral superconductor Sr2RuO4

description: Sr2RuO4 is a 2-D layered perovskite oxide metal which becomes superconducting below 1.5K. There is strong experimental evidence that the superconducting wavefunction is unconventional with a triplet spin part and orbital part with belongs to a two-dimensional representation. It is likely that the order parameter is chiral.  It is widely believed that the Cooper pairing is mediated by ferromagnetic spin fluctuations. Thus Sr2RuO4 would be an electronic analogue of superfluid He-3 which is also believed to be mediated by spin fluctuations.  Here we propose to search for the paramagnons or spin fluctuations which might cause the pairing.
DOI: 10.5286/isis.e.rb1720040
title: Investigation of new  fluorinated and reductively defluorinated phases with Ruddlesden-Popper type structure

description: Fluoride Ion Batteries (FIB) are alternative energy storage systems which work based on the transport of fluoride ions between the electrochemically active electrode materials. Such battery systems were based on conversion materials (transformation of a metal to a metal fluoride and vice versa). Intercalation type electrodes are known to be favourable regarding their battery kinetics and cycling stability. In this respect, we aim to investigate new compounds for the use as electrode materials, and found that Ruddlesden-Popper compounds Srn+1TinO3n+1-yF2y (charged state) can serve as intercalation based anode materials. So far, structural investigations of the electrode materials is difficult (composites), and we therefore developed a new topochemical reductive defluorination method to prepare larger amounts of the compounds in their discharged state (Srn+1TinO3n+1-yF2y-z, 0
DOI: 10.5286/isis.e.rb1720175
title: Crystal structure of the new oxyapatite-based ALa9(GeO4)6O2 (A = Li-Rb) phosphors

description: Advanced luminescent materials exhibiting downconversion are important components of next-generation photovoltaic devices aimed at minimizing the spectral mismatch losses in solar cells. We showed that germanates with the general formula ALa9(GeO4)6O2 (A = Li, Na, K, Rb) can effectively downconvert high-energy photons from the visible and near-IR parts of the spectrum into far-IR photons. The optical transitions of many rare-earth ions are influenced by small changes in the crystal structure of their hosts. In order to control luminescent properties of these materials, neutron diffraction experiments are essential. The experiments will help to determine the oxygen and alkaline metal positions, cation distributions, and to refine oxygen deficiency. Obtained structural models will be used for DFT calculations aimed at explaining the differences in luminescent properties of these compounds.
DOI: 10.5286/isis.e.rb1720272
title: Hydration effects in gels for water splitting.

description: Storing the energy available from the sun as a fuel that can be used anytime is a major global challenge. Organic materials synthesised from abundant elements that can harness solar energy are being widely researched. Our approach is to use some of these materials (perylene bisimides) in a photo-electrochemical cell to split water into oxygen and hydrogen that can be stored as a gas and used whenever necessary. These materials are made using self-assembly to form gels that can either be used directly as wet materials or dried and re-hydrated for better stability. Using small angle neutron scattering we will investigate where and how well water is located in the gel and dried gel materials. Neutrons can detect the difference between water and heavy water, which we will exploit to obtain information about where the water is located when the gel is re-hydrated.
DOI: 10.5286/isis.e.rb1720276
title: Neutron diffraction study of antiperovskite Mn3CoXN: a potential magnetocaloric material at room temperature

description: Materials exhibiting giant magnetocaloric effect  (i.e. the large temperature change under a magnetic field variation) are the most promising type for magnetic refrigeration. However, in order to gain from this giant effect, it is necessary for the material to show first order magnetic transition around room temperature. Some antiperovskite intermetallics Mn3AX (A= Ni, Cu, Zn, Ga, etc.; X=N, C)  present isotropic volume contraction (first-order transition) accompanied by a magnetic transition, indicating the presence of strong magnetostructural coupling. Therefore, antiperovskites may be an appropriate playground to exploit magnetocaloric material. We recently found Mn3CoN might serve as a promising system for exploring MCE around room temperature. To reveal the magnetostructural coupling,  we intend to conduct neutron diffraction.