cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1910345
title: Determination of the magnetic structure in the coupled trimer spin system Ba4NbMn3O12

description: When isolated spin clusters are weakly coupled to each other, zero-dimensional quantum and three-dimensional collective magnetism concomitantly occur. This is envisioned in the low-lying magnetic excitations, including transverse and longitudinal magnon modes along with gapped localized excitations. The newly discovered hexagonal perovskite Ba4NbMn3O12 constitutes Mn3O12 trimers made of three face-sharing MnO6 octahedra, with the trimers arranged in triangular planes. Ba4NbMn3O12 shows a ferromagnetic type order (possible ferrimagnetic order) at 42 K, yet with a small negative Curie-Weiss temperature of -4 K. In addition, the local spin alignment with the individual trimers occurs at much higher temperatures than the 3D long-range order. This energy hierarchy renders Ba4NbMn3O12 an attracting platform to explore a crossover of molecular magnetism to more collective behavior.
DOI: 10.5286/isis.e.rb1910412
title: Investigating the magnetic structure of the solid solution PrCr(1-x)MnxO3

description: Rare-earth (A= La, Ce, Nd, Pr) orthochromites (A CrO3) and orthomanganites (A MnO3) are of interest due to the number of unusual physical properties they possess, displaying exotic magnetic structures, and demonstrating promising characteristics such as magnetoresistance. Understanding how to tune the characteristics of these materials is important for future applications of functional oxides. Structurally, these materials are very similar, usually crystallising with orthorhombic symmetry, with corner shared oxygen octahedra around the B-site. Despite this, the physical properties are altered considerably depending on the contents of the A- and B-sites, due the level of distortion of the octahedra, and the type of magnetic interactions present. The aim of this study is to consider the effect of Mn/Cr content on the low temperature magnetic properties of the PrCrMnO3 series.
DOI: 10.5286/isis.e.rb1910432
title: Neutron scattering investigation of spin-dynamics in the S= 1/2 trimer chain compound Na2Cu3Ge4O12

description: Spin-trimer chain systems are of current interest due to unconventional properties arising from the strong quantum fluctuations and topology, such as, quantum phenomenon of magnetization plateau.  The presence or absence of plateaus is strongly related to the relative strength and sign of the intratrimer and intertrimer exchange interactions. Therefore, determination of the sign and strength of the exchange interactions is essential to shed light on quantum magnetization plateau. We propose inelastic neutron scattering studies on spin-1/2 trimer chain compound Na2Cu3Ge4O12 using the MERLIN spectrometer to determine the spin Hamiltonian. The present experimental study will shed light on the unconventional magnetic properties of the spin trimer chains such as quantum phenomenon of magnetization plateau. Experimental results will be useful to develop theoretical models in such systems.
DOI: 10.5286/isis.e.rb1910501
title: Determination of successive magnetic orders of a new honeycomb-based multiferroic antiferromagnet

description: Novel functionality in condensed matter physics is one of fastest developing fields, aiming for possible future applications including quantum computing, electronic devices and so on, leading to continuous discoveries of new materials and phenomena. This is part of these efforts in our research project to explore the novel functionality in quantum magnets. Here we propose to investigate a newly synthesized honeycomb-based multiferroic candidate with neutron diffractions to determine magnetic structures in successive magnetic transitions. We aim to understand the role of magnetic structures with emerging complex polarisations, hoping to have good ideas for designing new functional multiferroic materials and applications.
DOI: 10.5286/isis.e.rb1610153
title: In-situ Neutron Diffraction Measurement combined with the First Cyclic Deformation of Additive Manufactured Ti-6Al-4V at High Temperature

description: As additive manufacturing (AM) is moving into the production of more heavily loaded end-use components, particularly within the aerospace sector, improved understanding of the performance of AM parts under cyclic load is essential.  Ti-6Al-4V is the most prevalent Ti alloy and widely used in aerospace.  The presence of heterogeneous microstructures, i.e. the continuous changes in texture, grain shape, distributions of phase and composition, has been observed from the bottom to the top (along the z direction) of the AM-built.  Here we propose to undertake an in-situ tensile-compressive loading of AM-built Ti-6Al-4V at 450°C combined with the neutron diffraction.  The proposed experiment will provide a mechanistic understanding of deformation of AM-built Ti-6Al-4V under cyclic loads.
DOI: 10.5286/isis.e.rb1610168
title: Phase behaviour in lanthanum antimony niobate proton conductors

description: Antimony substituted lanthanum niobium oxide is a recently developed proton conductor with potential use in fuel cells, gas sensors and steam electrolysers Our preliminary work has revealed that not only does antimony substitution enhance conductivity, it also stabilizes the highly conducting scheelite phase to room temperature in contrast to the unsubstituted system which exhibits the more poorly conducting furgusonite structure at ambient temperatures. Other work suggests that the oxide ion separation distance plays a major role in determining the enthalpy of proton diffusion in these systems. A study of the correlation between electrical behaviour and oxide ion separation distance and distortion in the metal coordination environment using neutron diffraction is proposed. Details of the individual contributions of antimony and niobium will be studied using a total scattering approach.
DOI: 10.5286/isis.e.rb1610284
title: Investigating the influence of the oxide on adsorption and corrosion of copper metal

description: Copper is an important industrial metal, predominantly used in electrical wiring and plumbing, as well as in power transformers. Throughout these applications, sulphur is known to be a strong corroder of copper, inducing catastrophic failure in the worst cases. Therefore, improving the understanding of how active sulphur species attack copper and how inhibitors interact with the surface can lead to better protection of these components.Through visible observations, XPS and previous neutron reflection (NR) measurements it is believed that the proportion of Cu(I):Cu(II) within the oxide at the surface has a strong influence on additive adsorption and subsequent sulphur corrosion. In this study we aim to prove this theory through in-situ measurement of changes at the corroding surface by NR.
DOI: 10.5286/isis.e.rb1620214
title: The effect of primary creep pre-straining on creep stress relaxation in P92 ferritic/martensitic steel

description: Residual stresses can have a significant effect on the integrity of high-temperature structures. Consequently, the interaction between residual stresses and creep deformation is persistent source of uncertainty in the design and assessment of high-temperature pressure systems such as those used in nuclear power reactors. This study will investigate the role of combined primary and secondary creep during the creep relaxation of residual stresses.  However, it has recently been shown that in some circumstances the majority of creep stress relaxation occurs during primary creep regime. In this study, we will remove the influence of primary creep by applying a creep pre-straining cycle to the specimens prior to the start of the experiment. In-situ creep relaxation tests will then be performed on pre-strained and non-pre-strained specimens, separated out the influence of these two regimes.
DOI: 10.5286/isis.e.rb1670542
title: Systematic characterization of internal fields and zero-field TN in layered organic antifferomagnets, deuterated k-(BEDT-TTF)2Cu[N(CN)2]ClxBr1-x  (x=0.25, 0.5, 0.75)
DOI: 10.5286/isis.e.rb1670552
title: Electron Transport Studies in Biological Molecules with respect to the Science of Aging
DOI: 10.5286/isis.e.rb1670568
title: muSR study of quantum atomic deuterium/hydrogen and their critical slowing behaviors in paratacamite Cu2(OD)3Cl/Cu2(OH)3Cl

description: Recently we found by muSR that the deuterium (D) atoms in the new ferroelectric compound  Co2(OD)3Cl were quantum atomic and showed a critical slowing down with Tc=230 K, which leaded to a deuterium long-range order and brought out a ferroelectric transition at TE=230 K.  Meanwhile in  Co2(OH)3Cl, quantum atomic H showed Tc=210 K with incomplete ordering. For the first time, the muSR technique is successfully applied to ferroelectrics. The magnetic frustration seems also played a role in the critical slowing. Now we have lobserved similar ferroelectric behaviors in paratacamite Cu2(OD)3Cl/ Cu2(OH)3Cl, which has a similar highly symmetric R-3m structure like Co(OD)3Cl/ Co(OH)3Cl but has much different magnetism. The proposed experiment will contribute greatly toward the establishment of utilizing the muSR technique to ferroelectricity, which is one of the major solid-state physics field.
DOI: 10.5286/isis.e.rb1710089
title: Oxygen ion diffusion in oxides

description: In order to detect oxygen diffusion in electrolyte materials in Solid Oxide Fuel Cells, we here want to propose a muSR experiment on three oxide electrolytes exhibitng good oxygen ionic conductivity at high temperatures. The principle behind the proposed experiment is that the implanted positive muons locate at the vicinity of O^{2-} ions so as to make a stable O-mu; bond in the electrolyte materials. Then, as temperature increases from room temperature, both O^{2-} and [Omu]^{1-} start to diffuse above a certain temperature. Since the O^{2-} ions diffuse through the channel formed in the cation lattice, namely, in the rigid skeleton, we could see the [Omu]-diffusion through the change in both the hopping rate and field distribution width, if the skeleton has a nuclear magnetic field. Note that oxygen diffusion is not detected by neutron and NMR mea
DOI: 10.5286/isis.e.rb1720104
title: Damage Tolerance of the CrMnFeCoNi High-Entropy Alloy at Cryogenic Temperatures

description: The mechanical properties required for metallic materials in most structural applications rarely can be achieved in pure metals and are generally attained through the addition of alloying elements. Traditionally, metallic alloys have consisted of a dominant element, such as iron in steels, to which small amounts of alloying elements are added, for example, carbon for strength. High-entropy alloys (HEAs) represent a new ﬁeld of metallurgy that focuses attention away from the corners of alloy phase diagrams towards their centres, thereby enabling numerous new materials. One of the most notable HEAs to date, CrMnFeCoNi, is a case in point and it has a strong dependence of the strength with the decrease of temperature. We propose to study this material at 7K to explore its application in relevant industry and the scientific mechanism behind this behavior.
DOI: 10.5286/isis.e.rb1720352
title: Introducing the O-antigen in Bacterial Outer Membrane in vitro Models Pt. II  The Langmuir approach

description: The Gram negative bacterial outer membrane protects the bacterium from external toxins such as antibiotics. This is partially responsible for Gram negative bacteria becoming the greatest emerging source of antibiotic resistance. We are developing models of these bacterial outer membranes and have successfully recreated the characteristic  lipid asymmetry (with lipopolysaccharide (LPS) on the outer leaflet and phospholipids on the inner) and also the water filled periplasm. In order to fully recreate the membranes we will need to incorporate more complex LPS versions to mimic pathogenic bacteria. We will incorporate LPS containing one or two O antigens into the final model at different densities to determine who much it increases the bilayer thickness. In future experimental programmes we aim to increase the LPS length to investigate how very long LPS behave.
DOI: 10.5286/isis.e.rb1720482
title: MUSR investigations of the spin-liquid ground sate in the new kagome lattice Cu3Zn(OH)6FBr

description: Unveiling quantum effects in materials at low temperatures, such as quantum spin-liquid behavior, have been a central task in condensed matter physics. A two-dimensional kagome antiferromagnet can achieve a spin-liquid ground state due to strong quantum fluctuations and geometrical frustrations, but the topological nature of its ground state and low-energy spin fluctuationsare still controversial. Recently, we have successfully synthesized polycrystalline of Cu3Zn(OH)6FBr with the barlowite type crystal structure. Our specific heat measurements show that there is no phase transition down to 50 mK in Cu3Zn(OH)6FBr and hence provides a unique opportunity to investigate spin-liquid ground state in this compound down to 50 mK using muon spin rotation and relaxation measurements. We would also measure Cu4(OH)6FBr, which exhibits an antiferromagnetic ordering at 15 K for a comparison.
DOI: 10.5286/isis.e.rb1810432
title: High pressure structural study of BaD2

description: Simple hydrides are of scientific interest due to their suitability for storage of hydrogen in the solid state. These materials also display a wealth of interesting physics, such as superconductivity under pressure, and high ionic conductivity at elevated temperatures. Recently BaH2 was observed to show a first order structural phase transition under applied pressure; as this was observed with X-rays, information on the positions of the hydrogen atoms was not observable. We propose to perform a high pressure neutron diffraction experiment on the isotopically similar BaD2 to determine the positions of the D atoms through the transition, providing valuable information on the nature of the high pressure phase.
DOI: 10.5286/isis.e.rb1810508
title: A robust metal-organic framework with exceptional capability for dynamic hydrocarbon separation under ambient conditions

description: The study of porous metal-organic framework (MOF) materials has attracted considerable attention.  We seek to develop new stable MOFs for practical separation of light hydrocarbons and request 3 days on WISH to study the preferred binding sites of adsorbed gas molecules (C2D2, C2D4, C2D6, C3D6 and C3D8) within a MOF (MFM-520). MFM-520 has shown excellent separation property of light hydrocarbons via dynamic breakthrough experiments under ambient conditions. The high resolution, low background and large d-spacing capabilities of WISH make it ideal for analysing the precise locations of gas molecules within these porous MOFs and to define the preferred orientations of molecules with respect to the binding sites on the pore surface. This study will reveal key structural insights into the exciting gas separation of this MOF.
DOI: 10.5286/isis.e.rb1820103
title: PROBING DRUG PHARMACODYNAMICS BY INS - THE EFFECT OF CISPLATIN-LIKE ANTICANCER DRUGS ON DNA

description: Cancer is a growing health problem worldwide, and thus the development of effective chemotherapeutic approaches is crucial for improving human health. Much effort has been put into the design of metal-based drugs, particularly Pt(II) and Pd(II) polyamine chelates acting through unconventional interactions with DNA. These agents have been extensively investigated by the authors in the last decade.Following previous QENS experiments that revealed a clear effect of these metal-based anticancer drugs on the dynamical behaviour of DNA through an impact on its hydration layer (RB1710167, paper under preparation), the present INS experiment aims to monitor drug-prompted structural changes in the nucleic acid as well as in its hydration shell. This is an innovative way of tackling a drug´s pharmacodynamics at a molecular level, water being suggested as a secondary pharmacological target.
DOI: 10.5286/isis.e.rb1820305
title: Lattice dynamics in the giant barocaloric Ammonium Sulfate

description: Given the challenges in providing efficient and non-harmful refrigeration, it is timely to study barocaloric systems, which offer cooling power via the application of pressure, something which is far more trivial to do than applying a magnetic field as required for magnetocalorics. The majority of caloric materials investigated so far have been based on expensive and relatively scarce rare-earths metals. Ammonium sulfate, by contrast, is widely and cheaply commercially available. It has been demonstrated that small changes in hydrostatic pressure drive giant inverse barocaloric effects near the ferroelectric phase transition. It is therefore our aim to investigate the phonon dispersion in this material near the transition to gain insight into the origin of the barocaloric effect. Successful measurements would be extended to applying hydrostatic pressure in the future.
DOI: 10.5286/isis.e.rb1820519
title: Variable temperature study of the structure of the new bimetallic, mixed anion fast ion conductor, Li0.5Na0.5(BD4)0.83I0.17

description: We propose 1 day of beam-time on GEM to probe changes in the crystal structure of the new fast Li+ conducting mixed-cation, mixed-anion phase, Li0.5Na0.5(BD4)0.83I0.17 as a function of temperature. Partial substitution of Li by Na and of BH4 by I stabilises the high pressure, rock salt structure of LiBH4 (HP-LiBH4) at room temperature and pressure. The scattering contrast for this composition by powder X-ray diffraction PXD is very low and so the aims of this experiment are to: (a) determine the precise positions and occupancies of the I- and (BD4)- anions and the Li+ cations, (b) establish the dynamic disorder of the (BD4)- anions, (c) resolve the thermal parameters of Li+ and elucidate the ionic conductivity mechanism.
DOI: 10.5286/isis.e.rb1820551
title: Determination of the magnetic structures of low-dimensional binary metal thiocyanates

description: Magnetic molecular framework materials, where the magnetic metal centres are linked together by molecules rather than single atoms, are a very exciting class of materials, as they can combine the interesting features of molecular frameworks: porosity, flexibility and modularity with useful magnetic behaviour. Thiocyanate (NCS) is particularly interesting as a linker as it is unusually effective at transmitting magnetic coupling, but very little is known about the magnetic behaviour of the simple binary metal thiocyanates. In this experiment, we will use neutron diffraction to determine the magnetic structures of four metal thiocyanates. This information will help us design new, functional magnetic materials.
DOI: 10.5286/isis.e.rb1820602
title: Phonons from diffraction and normal mode analysis in HMT

description: With the overall aim of extending the information derivable in a neutron  single crystal diffraction experiment beyond the static structure, we are proposing to perform a multi-temperature study of the model system hexamethylenetetramine (HMT) both in the hydrogenated and deuterated form. Two main aspects will be studied: 1) fitting a model potential that include phonons to the diffuse scattering at 300K and 2) perform a full normal mode analysis on data at 10K, 50K, 120K,180K and 250K to benchmark the ability to carry out a similar analysis using powder data from HRPD. The mean square displacements obtained in single crystal diffraction will also be compared to those derived in neutron Compton scattering on VESUVIO.
DOI: 10.5286/isis.e.rb1900057
title: Small-angle neutron scattering study of human growth hormone-surfactant complexes

description: Liquid pharmaceutical formulations are commonly comprised of proteins and surfactants, which interact in solution in order to provide an increase in system stability. Although these systems have been significantly investigated in the last few years, there is a lack of consensus concerning the interaction mechanism between proteins and surfactants. We believe that contrast variation small-angle neutron scattering can provide specific information about these systems and contribute to resolving the puzzle. In this experiment we aim to elucidate the interactions between human growth hormone and a prototypical anionic amphiphiles at room temperature. The use of isotope labelling and contrast matching will provide detailed information about individual parts of the system, which will then be co-refined in order to provide structural information of the protein-surfactant complexes as a whole.
DOI: 10.5286/isis.e.rb1900060
title: Probing Chemical Order in FeNi Alloys

description: A promising candidate for low-cost, high performing permanent magnet materials is the chemically ordered L10 FeNi compound. This phase is only observed naturally in select meteorites, and is notoriously difficult to form on laboratory time scales due to very low atomic motilities. Currently, artificial synthesis has only been achieved in ultrathin films or in irradiated materials. However, recent neutron diffraction studies carried out by our group has demonstrated evidence of a chemically disordered tetragonal (A6-type) phase in FeNi, which is proposed to be a transitional phase linking chemically disordered FeNi with chemically ordered L10 FeNi. To pursue this work, bulk alloys of doped FeNi were subjected to severe plastic deformation followed by a specialized annealing procedure using a custom built furnace; this is hypothesized to promote the formation of the A6 and L10 FeNi phases.
DOI: 10.5286/isis.e.rb1900149
title: Neutron diffraction and Neutron Resonance Transmission Analysis of a 2nd-1st century bimetallic sword fragment from China

description: We propose to perform Neutron Diffraction (ND) and Neutron Resonance Transmission Analysis (NRTA) of two 2nd-1st century bimetallic sword fragments from China, in order to investigate their composite structure: the swords have an iron blade mounted on a bronze grip.
DOI: 10.5286/isis.e.rb1910021
title: Probing the dynamics of silica supported imidazolium halide catalysts for carbon dioxide utilisation

description: Atmospheric levels of CO2 are increasing at uncontrolled levels and as such methods of CO2 utilisation are being researched. A key reaction for this purpose is the coupling of CO2 with epoxides to form cyclic carbonates. The authors have shown that silica supported imidazolium halides are highly active catalysts for this reaction. The literature has shown that hydrogen bonding to the epoxide helps to initiate the reaction and we believe that the silanols on the silica surface are responsible for the high activity. The proposed experiment is to perform elastic window scans on a reference silica and four functionalised silica samples with different loadings, each with varying access to surface silanols. An elastic window scan and QENS measurements on each sample will require 24 hours on the IRIS spectrometer so we are asking for 5 days of beamtime.
DOI: 10.5286/isis.e.rb1910081
title: INS Study of Bio-oil on a Hydrodeoxygenation Catalyst

description: The Indonesian government has recently passed a new policy regarding a mandatory regulation for all gas stations nationwide to replace existing diesel fuel to B-20 biofuel. Bio-oil is a promising source of biofuel which is readily obtained from the pyrolysis of biomass waste hence maintaining a closed carbon cycle making the environment cleaner. The high content of oxygenates in bio-oil, however, remains a problem that results in low heating values, chemical and thermal instability, and immiscibility with hydrocarbon fuels. One effective upgrading process is the hydrotreatment of bio-oil using a hydrodeoxygenation catalyst. We have synthesised a novel catalyst based on bentonite, i.e. NiMoS/PILC which show superior activity to the commercial NiMoS/Al2O3. To this end, we wish to use INS to study the details of the interaction between the catalyst and the compounds contained in bio-oil.