cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1710476
title: Weyl Points in the Magnetic Excitations of Er2Ti2O7

description: In the condensed matter community the last ten years have seen a revolution in our understanding of how topology influences the properties of solids. A famous example from the last couple of years is the class of Weyl semi-metals. These are solids, such as TaAs (as demonstrated in 2015), which have various unusual properties driven by the presence of "Weyl points" in their electronic band structure. These Weyl points may also exist in the magnetic excitations of materials leading to analogous unusual properties which have not yet been explored simply because concrete examples have not been established. This proposal, which is motivated by calculations of the spin waves and Berry curvature on a well characterized antiferromagnet, is to see these Weyl points in a real magnetic insulator for the first time.
DOI: 10.5286/isis.e.rb1710494
title: Hydrogen disorder in benzoic acid

description: In a previous experiment on VESUVIO (RB 1520359) we aimed at investigating para-iodo-benzoic acid (IBA), in particular the onset in temperature for the appearance of the hydrogen disorder in the crystal as compared to the parent compound benzoic acid (BA). The nature of the disordered positions of the hydrogen atoms in substituted crystalline benzoic acids is a long standing debate. The disorder in the main compound, benzoic acid (BA), has been investigated with many different techniques ranging from crystallography to vibrational spectroscopy and interpretations are ranging from chemical tautomerism to quantum condensation. Our NCS results show also that the origin of the disorder is due to thermally activated stochastic proton jumps across the hydrogen bond. To reinforce this hypothesis, we propose to measure a partially deuterated BA.
DOI: 10.5286/isis.e.rb1720199
title: Structural Investigations of Substituted Bornites

description: Thermoelectric (TE) materials enable the recovery of useful electrical energy from waste heat. High-efficiency requires a high electrical conductivity to be coupled with a high Seebeck coefficient and low thermal conductivity. The very low thermal conductivity of bornite, a naturally occurring copper-iron sulphide, makes it an attractive candidate TE material. Our investigations into improving the electrical properties of bornite without impairing the thermal conductivity have led to the discovery of synthetic analogues that show excellent TE performance. We wish to investigate the detailed structure of these materials by powder neutron diffraction. We will study the evolution of cation/vacancy ordering through two structural transitions and the behaviour of the copper sub-lattice, which appears to be responsible for a reduction in lattice thermal conductivity.
DOI: 10.5286/isis.e.rb1720213
title: High pressure behaviour of the cubic NTE material Cd(CN)2

description: Cubic cadmium(II) cyanide shows the most pronounced isotropic NTE effect known, with behaviour more than twice as extreme as that of better known materials such as ZrW2O8. Because NTE is driven by soft phonons, it is possible to gain important mechanistic insight from the structural response of Cd(CN)2 as a function of both temperature and pressure. This specific proposal aims to explore the GPa-range high-pressure behaviour of the compound. We will characterise any new phases that emerge at these higher pressures. The relationship of these phases to the ambient structure gives a direct indication of soft modes, and hence the mechanism for NTE.
DOI: 10.5286/isis.e.rb1720240
title: µSR investigations of multiband triplet superconductivity in a quasi-1D system: Rb2Cr3As3

description: Recently the discovery of superconductivity in the quasi-1D Rb2Cr3As3 with TC=4.8 K has attracted considerable interest. The unconventional superconductivity has been revealed by both experimental and theoretical investigations. As theoretical calculations have pointed out that A2Cr3As3 is near magnetic order and SC is relevant to strong spin fluctuations, we propose to carry out muon spin rotation and relaxation  measurements on Rb2Cr3As3 using the MUSR spectrometer to probe the superconducting state, nature of the gap, pairing mechanism and order parameters. We have already carried out the musr measurements of K2Cr3As3 and Cs2Cr3As3 ( D. T. Adroja, ea al. , PRB 92, 134505 (2015) and  D. T. Adroja, ea al. , JPSJ 86, 044710 (2017) ),and found that the superconductivity in these system is related to the magnitism . We would like to measure Rb2Cr3As3 for comparison.
DOI: 10.5286/isis.e.rb1720245
title: Repeat of Assembling floating, very sparsely tethered, protein-lipid bilayers.

description: This was granted 2 days but problems with our samples meant that no data was got. After successful practice on Biacore offline, failure was due to using a new  (faulty) batch of thiolipid /linker. By using a single batch for both we will avoid this problem in future. Tethered floating lipid bilayers are useful models of biological membranes in which a phospholipid bilayer is tethered to a solid surface by a molecular linker. They promise an additional method to help us build accurate models of all types of membranes. Our previous POLREF experiments showed that we can assemble lipid only bilayers at very low tether densities which is important to minimise their effect on the membrane. Here we wish to show that we can insert and characterise proteins within the lipid bilayer which is another important step in creating useful models of living membranes in neutron tractable sample environmen
DOI: 10.5286/isis.e.rb1720337
title: A High-Pressure Study of TNT

description: This proposal will explore the effect of elevated pressure on the widely used civil and military explosive TNT (trinitrotoluene).  We are proposing a careful high-pressure neutron diffraction study on both polymorphs of TNT under hydrostatic conditions, with the aims of (i) identifying the evolution of structure as a function of pressure, including the changes in intermolecular interactions, (ii) exploring in detail the structural changes that occur near 2 GPa in the monoclinic form, (iii) exploring for the first time the effect of pressure on the orthorhombic form, and (iv) determining more reliable equations of state for the two polymorphs.  These experimental results will be compared with the outputs from DFT-D calculations on each of the polymorphs as a function of pressure.  These results will provide an enhanced understanding of the behaviour of this widely used material.
DOI: 10.5286/isis.e.rb1720459
title: Probing the Time Reversal Symmetry Breaking in Noncentrosymmetric Topological Superconducting Candidate Mo(Te1−xSex)2 (x = 0, 0.05 and 0.15)

description: Research on the superconductivity in a Weyl semimetal is an interesting area of research due to possibility of realizing exotic phenomenon such as Morona fermions.  The, interesting, semi-metallic band dispersion may originate from the topologically protected crossing points in the vicinity of the Fermi level. Here we propose to study the topological superconductivity in the new Weyl semimetals Mo(Te1−xSex)2 (x = 0, 0.05 and 0.15).
DOI: 10.5286/isis.e.rb1768000
title: μSR Study of Non-Centrosymmetric Superconductor TaOs

description: The search for unconventional superconductors has been a cornerstone of research in condensed matter physics for many years. Recently a key research interest has been superconducting materials with non-centrosymmetric (NCS) crystal structures. The lack of inversion symmetry leads to an antisymmetric spin-orbit coupling, a split Fermi surface, and the potential for upper critical fields that are vastly more than the Pauli paramagnet limiting field. Theoretical predictions expect that NCS superconductors are also prime candidates for realising a highly unconventional superconducting ground state that is an admixture of spin-triplet and spin-singlet Cooper pairs.In this proposal, we intend to study superconducting ground state properties of noncentrosymmetric TaOs using TF and LT modes to understand the pairing mechanism of non-centrosymmetric superconductor TaOS.
DOI: 10.5286/isis.e.rb1410142
title: Temperature driven spin incoherence and criticality in the Luttinger liquid phase of an ideal spin ladder material

description: We propose an experiment on the low energy spectrometer LET to study temperature effects on the Luttinger liquid (LL) phase on the spin ladder geometry. The spin ladder material (HPIP)2CuCl4 (BPCC), is a near ideal realisation of the a spin ladder, with exchanges which enable all excitations in the entire phase diagram to be studied. Firstly we will use the exceptional resolution of LET with the 9T magnet and dilution to finish studying the field dependence of the excitations of the LL phase. Recent theoretical developments have highlighted the effect of temperature on spin/charge coherence in the LL phase. Full measurements of this phase have never been performed and can lead to a greater understanding of its universality class. Finally we propose to study critical scaling laws at both quantum critical points of the spin ladder phase diagram, which has never before been attempted.
DOI: 10.5286/isis.e.rb1410536
title: Residual stress determination via computer modelling, neutron diffraction and destructive sectioning techniques in ASTM F-75 knee implant ca

description: ASTM F75, a cobalt-chrome alloy, is the most dominant material used for total biomedical joint replacements due to the combination of its wear properties, corrosion resistance and bio-compatibility. As a result ASTM F75 is the material of choice for DePuys next-generation family of knee implants. These implants are investment cast to a near net shape and then finished by grinding. As material is removed, residual stress (RS) is released, allowing the part to distort to a new equilibrium state. This unpredictable dimensional distortion is frequently observed and is a significant cause of scrap. It is therefore essential to determine RS magnitudes and distributions within these parts to achieve predictability in the manufacture of high tolerance implants. A number femoral castings, as detailed in the experimental plan are proposed for neutron diffraction RS determination.
DOI: 10.5286/isis.e.rb1481003
title: Programme Access Rosseinsky/Claridge
DOI: 10.5286/isis.e.rb1500007
title: Energy Harvesting : Study and modeling of binary and ternary mixtures in liquid phase by neutron diffraction
DOI: 10.5286/isis.e.rb1500012
title: Neutron Diffraction as Tool to Probe the Magnetic Exchange Bias in a Novel Compound Ce2PdGe3
DOI: 10.5286/isis.e.rb1500019
title: The influence of hydrogen bonding on the melting points of sulfonate-based protic organic salts
DOI: 10.5286/isis.e.rb1510389
title: Chasing the symmetry of the BiFeO3 γ-phase in the isostructural A- and B-site doped Bi1-xLaxFeO3 and BiFe1-xMnxFeO3 materials

description: BiFeO3 is by far the most widely studied multiferroic material and yet many mysteries remain in the phase diagram. One mystery is the crystal structure of the high T gamma phase. Previous work by us has demonstrated that this phase is not cubic as previously reported. More recently we have shown that the gamma phase of BiFe0.7Mn0.3O3 is also not cubic and is better described by the space group Rbar3c. However, this symmetry does not seem to satisfy the data collected for BiFeO3. We propose to investigate the high T phase diagram of Mn doped BiFeO3 with the aim of elucidating this unusual behaviour further. In addition we aim to probe the isostructural Bi1-xLaxFeO3 system. Conducting these experiments at the same time will allow us to investigate the effects of A- and B-site doping ultimately gaining a better understanding of not only both of these systems but also BiFeO3.
DOI: 10.5286/isis.e.rb1510415
title: Investigating the structural effects of bioactivity enhancements in doped hydroxyapatite.

description: We wish to gain a deeper understanding of where dopant cations and anions reside in hydroxyapatite (HA).  We will substitute Sr, Si, 11B and S into the HA structure and determine which sites in the unit cell each dopant preferentially occupies. Data such as shifts in interatomic distances or distortions to PO43- tetrahedral would also be useful.  Such information cannot be obtained by simple XRD analysis (figure 1). However, by understanding how the charge and ionic radius of dopants ions dictates where they reside in mono-substituted HAs, we believe we can more quickly tailor novel substituted HAs to deliver a specific type of bioactivity behaviour. This increased understanding allows for improved experimental design and research efficiency when developing next generation bioceramics for applications in orthopaedic fields.
DOI: 10.5286/isis.e.rb1567495
title: Studying hydrogen (deuterium) dynamics in geometrically frustrated CO2(OH)3Cl and CO2(OH)3Br to uncover new multiferroics II
DOI: 10.5286/isis.e.rb1567508
title: Solute-vacancy clustering in Al-Mg-Si and Al-Si alloys
DOI: 10.5286/isis.e.rb1610088
title: Characterisation of a Fe(gamma)-Ni-Fe(alpha) Multi-material fiducial marker

description: The experiment involves the characterisation of a multi-material fiducial marker (MMFM) with respect to scattering intensities as a function of marker position. If this relationship can be established, the MMFM position can be determined from a single measurement. The rationale behind this approach is to find a means of using the beam-sample interaction to find the sample with respect to the beam, but in a more efficient manner than multiple wall scans. The beam time being applied for here will be used to determine the smallest practical gauge volume and expected positional accuracies achievable when using this technique. The experiment will also serve as a validation of simulated results. Should this technique be deemed viable, the SScanSS system can be implemented on pulsed and constant wavelength neutron strain scanning instruments without the use of a multi-axes arm and touch probe.
DOI: 10.5286/isis.e.rb1610133
title: Oxidation of bilayer of DPPC  on a mineral interface by aqueous OH radical kinetics and mechanistic information for Atmospheric Science

description: Oxidation of atmospheric aerosol can produce cloud condensation nuclei capable of changing the reflectivity and lifetime of clouds. The oxidation of organic film on atmospheric mineral dust may activate mineral dust  into cloud droplets. To assess the atmospheric importance the chemical lifetime of the organic material to a common atmospheric oxidant (OH radical) must be measured and compared to deposition lifetime of the mineral aerosol (4-10 days). The chemical lifetime will be assessed by measuring the rate of oxidation of a bilayer of a lipid DPPC from the solid-liquid interface of a silica mineral window, using neutron reflection. Selective deuteration, the ability to measure film thickness and amount of material at the solid-liquid interface will allow chemical mechanism to be deduced. Preliminary studies show the experiment viable, and these data are needed for publication.
DOI: 10.5286/isis.e.rb1620075
title: Search for Weyl Magnon in LiGaCr4O8

description: Weyl magnon in the chromium-based breathing pyrochlores is a recently predicted novel magnetic excitation state. Similar to its anolog, Weyl fermion in the electric systems, Weyl magnon refers to a topologically linear band touch in the spin wave spectrum of a magnetic ordered phase, making neutron scattering a natural method to probe this excitation. LiGaCr4O8 is a promising material to support Weyl magnon excitations, compared with the theoretical phase diagram. Thus, the spin wave spectrum is worth being measured. A linear touch of two spin wave branches is expected to appear at certain (Q, E) position in this experiment, and the temperature dependence of Weyl magnon excitations will also be studied.  For this experiment, we are going to apply for MERLIN for 6 days.
DOI: 10.5286/isis.e.rb1620208
title: Magnetic order in polar oxides: Mn2FeWO6 and Mn2MnWO6

description: Magnetoelectric materials, combining properties associated with magnetic and ferroelectric memory applications (e.g. in hard drives) are difficult to prepare but would represent a huge step forward in memory devices. Recently, theoretical work has highlighted several new classes of materials that might display such properties. One such family is derived from the corundum (Al2O3) structure but with various combinations of cations (including those with magnetic moments) instead of Al3+ cations. We propose to use neutron powder diffraction to investigate the structural chemistry and magnetic behaviour of two such materials. This understanding will be invaluable to guide future experimental and theoretical work to develop new materials with optimised properties.
DOI: 10.5286/isis.e.rb1620278
title: Cation reorientation dynamics in a metal formate perovskite

description: Hybrid metal-organic perovskites are promising functional materials, but the complex interactions between organic cations and the framework surrounding them are difficult to model. We have recently proposed, on the basis of total neutron scattering data, that in the high-temperature phase of dimethylammonium manganese formate, the disordered (CH3)2NH2+ ion jumps between more orientations than are apparent from traditional crystallographic models. We propose here to test our new model by probing the quasi-elastic neutron scattering from the cation rotation. Analysis of the elastic incoherent structure factor as a function of temperature will enable us to confirm the number of rotational orientations available to the cation and measure the activation energy for hopping between them. The results will be relevant to the design of new framework materials with targeted dielectric properties.
DOI: 10.5286/isis.e.rb1620370
title: Pressure-induced phase transitions in methylammonium lead iodide

description: Methylammonium lead iodide has recently been recognised as an excellent photovoltaic material, with energy conversion efficient of over 20% with the prospect of gaining higher efficiencies. The crystal structure at ambient shows two phase transitions involving ordering of the orientation of the polar methylammonium molecular cation and tilts of the PbI6 octahedra. Recently there has been a report of a high-pressure phase transition to a completely new phase. We plan to study this phase transition, exploiting the fact that neutron diffraction can give detail on this system (such as concerning the orientation of the methylammonium molecular cation) that cannot be obtained by x-ray diffraction. Understanding the structural flexibility of this material under changing conditions (temperature and/or pressure) is important to support future developments.
DOI: 10.5286/isis.e.rb1620408
title: Studies of propene formation by gasoline cracking in steamed ZSM-5 by INS

description: Fluidised Catalytic Cracking (FCC) units (shown below) are one of the major conversion units in modern petrochemical refineries. ZSM-5 additives. These are used in FCC units to convert gasoline (mainly gasoline olefins) into lighter C3 and C4 olefins (propene and butenes).  Propene is a key feedstock for downstream petrochemical industry and plays a major role in a variety of polypropene products in the market.  There is a global supply shortage of propene and improving propene yields from FCC units is seen as one strategy for meeting that supply gap. This proposal, and a parallel QENS proposal, aims to understand how steam dealumination of ZSM-5 (which generates the working catalyst) modifies the behaviour of a model long-chain alkene reactant (1-octene) and the product, propene.
DOI: 10.5286/isis.e.rb1620415
title: Probing Magnesium Diffusion in MgxMn3-xO4 Spinels with muSR

description: Energy storage with increased density is required for electronic devices, electric vehicles, and smart grids. Current lithium ion battery technology utilizes cathodes with high voltage and high capacity against a graphitic carbon anode, shuttling Li ions back and forth on charge and discharge in a non-aqueous electrolyte. Alternative strategies to increase energy density are under heavy investigation throughout chemistry, focusing on the beyond Li-ion space. Increasing the energy density at the cell level can be achieved by the use of pure metal anodes instead of carbon, however, dendritic growth from pure metal anodes is a major safety problem. Fortunately, some metals are known to strip and plate without such issues. Mg is one such metal that may also permit solid state intercalation. Here we will probe Mg diffusion in the solid state, typically thought to be too slow for batteries.
DOI: 10.5286/isis.e.rb1620470
title: Search for magnetic order in the coupled S=1/2 two-leg spin ladder system Ba2CuTeO6

description: Ba2CuTeO6 is a newly discovered S=1/2 spin ladder system containing Cu2+ ladders. Our experiments indicate that this material is in very close proximity to the quantum critical point of the coupled two-leg spin ladder system. Ba2CuTeO6 displays ideal ladder behaviour in magnetic susceptibility down to approximately T = 25 K. Below 25 K the behaviour deviates from that of a ladder and a cusp is seen at 16 K indicating magnetic ordering. However, NMR, specific heat and powder neutron diffraction experiments have not detected any long-range ordering at this temperature, suggesting the order is marginal. We propose to search in more detail for signs of long-range magnetic order and also investigate the magnetic correlations in Ba2CuTeO6 using WISH.
DOI: 10.5286/isis.e.rb1700054
title: Gamma-Ray Measurements with HPGe spectrometer

description: Gamma-ray background is often the main background source inneutron beamlines at new generation spallation facilities. Thegamma-ray components are produced within the target/reflector/moderator assemblies, in the beamline components,such as guides/shielding, in the sample area and in thesurrounding enclosure. Characterization of the gamma backgroundon a neutron spectrometer is of paramount importanceto determine its best operational conditions. This is particularlyrelevant for beamlines employing gamma-sensitive detectors.With this experiment we will attempt for the first time to measure the gamma-ray background of ChipIR by using a HPGe spectrometer.
DOI: 10.5286/isis.e.rb1700081
title: Optimizing Residual Stresses in Wind Turbine for increased lifespan

description: Fatigue is a major concern in the lifetime of wind turbine components and is one of the most important design parameters in wind power from a structural point of view. The fatigue life is influenced by the components residual stresses. To improve the fatigue life of wind turbine components, understanding and predicting residual stresses are of great interest.This projects aims to measure the residual stresses in cast wind turbine component with neutron scattering. Measured and modelled residual stresses will be compared to validate a method for predicting the residual stress of the cast steel components. The proposed experiment will be a first step in this project. The idea being to provide stress maps (profiles) on dedicated location for a critical component of the wind turbine.
DOI: 10.5286/isis.e.rb1710017
title: Probing the magnetic and structural correlations in Co1-xNixTeO4: (x=0, 0.5 & 1) : Neutron diffraction perspective

description: Transition metals (TMs) and their complexes are current examples of such materials which show new functionality, improved performances and greater versatility and have become the key drivers of innovation. In the same scenario, we present a series of new TM tellurate (TMTeO4 with TM = Co, Ni or 2×TM0.5Te0.5O2 analogous to VO2) compounds, for the first time. To the best of our knowledge, these TMTeO4 systems are completely new to explore, both from the fundamental as well as the applied physics perspectives. Towards this, the analysis of detailed neutron diffraction measurements will explore the structural and magnetic correlations to unravel the underlying phenomenon.