cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1710182
title: The structural role of hydrogen and other guest atoms in graphitic carbon nitrides

description: Carbon nitrides are emerging as an important class of materials with applications that range from Li+ ion and electronic charge storage in batteries and supercapacitors, visible-UV light harvesting for photocatalysis and photovoltaics, to fuel cell and electrolyser catalyst supports. The focus of this study are the polytriazine imide (PTI) materials, which are the only crystalline graphitic carbon nitrides that can be synthesised readily and reproducibly from molten LiCL. Despite the interest in these materials, the structure is unknown, especially the location of H and Li. Furhtermore, a recent observation has been that the Li and Cl can be removed from the PTI materials by washing with water. This can influence properties such as water-splitting. The goal of this study is to locate guest atoms (Li and H, which cannot be seen by X-rays) in these carbon nitrides using neutron scattering.
DOI: 10.5286/isis.e.rb1710482
title: Measuring stoichiometry in the lithium amide-imide solid solution with negative muons

description: The lithium amide-imide solid solution has been shown to have promising properties for application in solid state hydrogen storage and ammonia decomposition catalysis. However, relatively little is known about the properties of the solid solution itself. A key step in understanding the system is a obtaining a reliable measure of the average stoichiometry of a sample. To date, it has proven difficult to achieve this with diffraction methods alone. Here, we request four days of experimental time on Port 4 at RIKEN to test the use of the X-ray spectrum from the decay of negative muons implanted into a series of lithium amide-imide samples as a method for determining their average stoichiometry. These data will be used as the basis for an investigation of the composition-dependent properties of the system.
DOI: 10.5286/isis.e.rb1500015
title: Inelastic neutron scattering in the novel reentrant spin-liquid kagome antiferromagnet ZnCu3(OH)6SO4
DOI: 10.5286/isis.e.rb1510039
title: Determinations of the Preferred Binding Sites within Extended Porous Frameworks

description: Constructing new porous metal-organic frameworks (MOFs) is receiving considerable attention worldwide and is a ¿hot topic¿ owing to their potential for gas storage, separation, and purification. We request 6 days on WISH to study the preferred binding sites and locations of adsorbed gas molecules (C2D2, C2D4, C2D6, C3D4, C3D6, C3D8, NO2, NO, and N2O) within two porous MOF materials as a function of different gas loadings. The high resolution and large d-spacing capabilities of WISH make it ideal for analysing the precise locations of gas molecules within these porous MOFs and their preferred orientation with respect to the functional groups on the pore surface.
DOI: 10.5286/isis.e.rb1510146
title: Polarised neutron investigations of the spin Seebeck effect

description: The spin Seebeck effect generates spin currents in various materials when they are subjected to a temperature gradient. These spin currents persist over length scales many orders of magnitude greater than the spin diffusion length and thus may hold the key to realising spintronics devices.We wish to continue a neutron reflectivity investigation into the archetypal spin Seebeck system, thin film yttrium iron garnet (YIG) on a substrate of gadolinium gallium garnet (GGG). It is known that when a thermal gradient is applied that a magnetisation gradient is produced, however this magnetic redistribution has never been directly observed. We aim to do just that, giving new insight into the effect, as well as to answer the questions our previous investigations posed.
DOI: 10.5286/isis.e.rb1510162
title: Magnetic and crystal structure of goethite FeOOD under pressure

description: We propose the first high P/T neutron diffraction measurements on goethite (FeOOH), both the ambient pressure alpha- as well as the high-pressure epsilon-phase, in the P/T range of 0-10 GPa and 300-500 K. Goethite is the most common ferric oxyhydroxide on Earth and possibly on Mars. The pressure dependence of its structure as a function of P and T has been studied by synchrotron x-ray diffraction which obviously could not detect hydrogen nor adress the issue of magnetic ordering. The experiments proposed here will allow locating the hydrogen/deuterium positions, revealing the behaviour of the H-bond as a function of strong compression, and will determine the pressure dependence of the Néel temperature. The results will contribute to a better understanding of H-bonded minerals as well as our understanding of magnetic ordering in fundamental iron-rich solids
DOI: 10.5286/isis.e.rb1510240
title: Superconductivity in the half-Heusler alloys RPdBi (R=Lu,Er)

description: These half-Heusler compounds are also semi-metals, with low carrier densities and non-trivial topological features.  The crystal structures are also non-centrosymmetric, which is interesting from a superconductivity point of view, as one expects an admixture of conventional spin singlet and unconventional spin triplet pairing states.  Additionally, the isostructural Er compound develops a magnetically ordered phase in the region of superconductivity.  It is not known if the ordering is anti-ferromagnetic, or a more exotic spin spiral state.  It is also unknown to what extent the magnetism plays a role with the superconductivity.  Muon spin rotation and relaxation is an excellent tool for studying systems such as this, and in this proposal we suggest a thorough investigation of the flux line lattice using transverse field uSR.  We will also search for spin triplet pairing in zero field.
DOI: 10.5286/isis.e.rb1510257
title: Field-induced transition in a brownmillerite

description: The objective of this proposal is to solve the field-induced magnetic structure of a newly synthesized brownmillerite.  Under normal conditions there are three different magnetic regions as a function of temperature, but we have found that the field/cooling path taken in field and temperature results in a very different magnetic state at lowest accessible temperatures. We have reason to believe that this metastable magnetic state originates from magnetic frustration that we have observed at higher temperature. In order to prove this, we will be accessing this non-equilibrium magnetic state by flash cooling a single crystal of the material down to 4 K within a large applied magnetic field, and then measuring the neutron diffraction pattern.
DOI: 10.5286/isis.e.rb1510331
title: The structure of dense fluid deuterium

description: It is partly due to  quantum effects that hydrogen (and deuterium) exhibits a dramatic compressibility: in its fluid state, prior to freezing at room temperature at 5.5 GPa, it experiences a volume reduction by a factor of 3. This huge compressibility raises the interesting prospect of using a structural measurement of the fluid to sample the, intermolecular interaction potential across an extremely wide range of molecular separations. Such an experiment is now feasible, on deuterium, using newly developed gas loading techniques, and we propose to measure the structure of the fluid up to 5.5 GPa. This measurement would also provide a determination of the D-D molecular bondlength which is currently unknown above ambient pressure. Due to orientational disorder, this cannot be determined by conventional crystallographic means.
DOI: 10.5286/isis.e.rb1510473
title: In situ NPD investigation of double perovskite manganites in wet hydrogen atmosphere for use as new anode materials for SOFC

description: The aim of the experiment is to investigate by means of in situ NPD the structural behavior of two new Mn-rich double perovskites compounds, NdBaCo1.5Mn0.5O5+d and NdBaMn2O5+d in actual anode working conditions (wet hydrogen, 600-1000°C) of Solid Oxide Fuel Cell (SOFC) to get insight into the ordered/disordered nature of the oxygen sublattice and determine the mechanism of oxygen diffusion. It is crucial to check if diffusion in wet hydrogen conditions at high temperature (HT) proceeds in the transition-metal layers as in related cobaltites cathodes LnBaCo2O5+d heated in air. Such experiment on SOFC anode materials has not been performed so far. POLARIS is requested because its high resolution and good statistics allow detection of subtle distortion and afford precise information on the oxygen content and position, essential to unambiguously establish the diffusion mechanism.
DOI: 10.5286/isis.e.rb1510479
title: Temperature effect on ultra-confined water in beryl, quantum to classical transition

description: Recently, we investigated dynamics of water in beryl, the structure of which contains 5 A diameter channels along the c-axis. INS spectra revealed that effective potential for water along the channels was significantly steeper than perpendicular. The observed 7 peaks (E=0.25 to 15meV) at T=1.5K were explained assuming water quantum rotation-translation tunneling across the channels. DINS study of beryl at T=4.3K showed narrow, anisotropic water proton momentum distribution with corresponding kinetic energy, Ek=95meV, which is much less than was previously observed in bulk water (~150 meV). We believe that the exceptionally small Ek in beryl is a result of water tunneling. In this proposal we would like to do DINS for beryl at T=45 and 260 K, where water does not tunnel anymore (should be more ¿classical¿), and for this we need 8 days at VESUVIO.
DOI: 10.5286/isis.e.rb1520012
title: Origin of the spin pseudogap in a Ni-doped Heisenberg AF spin-1/2 chain

description: Heisenberg antiferromagnetic (HAF) S = ½ chains are famous for their gapless magnetic excitation spectrum. Interestingly, in SrCuO2 and Sr2CuO3, which are some of the best realizations of such chains, a spin pseudogap was found to open upon introduction of impurities. While studying SrCuO2 with neutrons we came up with an explanation for the pseudogap based on theoretical treatment of broken chains which reproduced the data very well. Unfortunately, SrCuO2 has a complication of the chains being arranged in pairs via weak and frustrated ferromagnetic coupling and the role of such a double-chain structure is unclear. In order to avoid this ambiguity and to understand the origin of the spin pseudogap, we propose to study Sr2CuO3 which has well isolated single-chains. The key question of the proposed experiment is how the size of the pseudogap is related to the concentration of impurities.
DOI: 10.5286/isis.e.rb1520305
title: Magnetic ordering at the Verwey transition in bulk like Fe3O4 thin films

description: Magnetite (Fe3O4) is a predicted half-metallic (100% spin polarised) ferromagnet with a high Curie temperature of ~858K. These properties make it well suited to use in spintronic applications such as magnetoresistance-based devices and spin injection into semiconductors. In bulk magnetite, the origin of the Verwey transition is still debated. However, thin film investigations of magnetite have been hindered by strain and growth defects leading to antiphase boundaries and altered magnetic properties. We have developed an optimised growth method for producing Fe3O4 thin films with bulk-like stoichiometry and properties. This provides a unique opportunity to study the magnetization depth dependence through the Verwey transition. The results will clarify the role of the interface and of strain on the density of defects, such as antiphase boundaries, and point the route to device fabrication.
DOI: 10.5286/isis.e.rb1520337
title: Magnetic state of Kagome-Triangular lattice antiferromagnet NaBa2Mn3F11

description: Geometrically frustrated magnets have attracted great interest because of their exotic orders at low temperatures. In case of classical Kagome Heisenberg antiferomagnet its highly-frustrated geometry causes macroscopic degeneracy and a coplanar 120° structure is realized by order-by-disorder mechanism. In real compounds small perturbations make drastic change in the eigenstates at low energies and a novel magnetic state is induced. NaBa2Mn3F11 is a new model compound for Kagome lattice antiferromagnet. The crystal structure is hexagonal and the space group is R-3c. Mn2+ ion carries spin S = 5/2 and the MnF7 pentagonal bipyramids form a Kagome lattice in the c plane. A remarkable difference from conventional Kagome lattice is found in the unusual exchange pathway of the 2nd neighbor interaction J2.　Therefore it is expected to realize intriguing magnetic structure in NaBa2Mn3F11.
DOI: 10.5286/isis.e.rb1520377
title: The influence of residual stress on fatigue crack growth and structural integrity assessment of offshore wind monopile structures

description: In order to characterise the fatigue crack growth (FCG) behaviour of the welded components used in offshore wind turbine monopiles, a number of tests have been performed on compact tension, C(T), specimens extracted from typical monopile weldment sections with the notch tip located in the HAZ region. The preliminary results from these tests have shown a ?bi-linear? FCG trend which is thought to be due to the compressive-tensile residual stress profiles available in the samples. It is therefore proposed that Neutron Diffraction (ND) measurements are performed on a slice of S355ML Steel welded plates and also a C(T) specimen extracted from the welded plates. The ND measurements from this experiment will facilitate the interpretation of the FCG behaviour in monopile welded structures and will contribute to the development of an optimum design for the offshore wind monopile structures.
DOI: 10.5286/isis.e.rb1540002
title: NTC2015
DOI: 10.5286/isis.e.rb1540012
title: NTC2015
DOI: 10.5286/isis.e.rb1600039
title: Low-dimensional glasses: Effect of occupational site disorder in the excess of low-frequency vibrational excitations
DOI: 10.5286/isis.e.rb1610014
title: Modelling the Structure of Metal-organic Framework Glasses

description: We have recently demonstrated the glass-forming ability of the family of hybrid micro-porous materials known as metal-organic frameworks (MOFs). Specifically, a family known as zeolitic imidazolate frameworks (ZIFs), consisting of Zn2+ ions linked by imidazolate  (C3H3N2-) based organic ligands, melt upon heating in argon, and their liquids can be quenched to form glasses with a tetrahedral metal-ligand-metal connectivity. Here we propose to use netron total scattering to probe the structure of one example of a glass formed by such a route. Furthermore, we wish to investigate the relationship between this structure, and the same MOF ball-milled.
DOI: 10.5286/isis.e.rb1610466
title: Effect of texture on generation of intergranular stresses in 316H

description: Intergranular stresses are generated in polycrystalline material due to anisotropic deformation during monotonic and cyclic loading. Such generated intergranular stresses can significantly affect the creep life and yield stress of materials operating at high temperature in power plants. In previous experiments at the same facility, the generation of intergranular stresses in non-textured material and how it affect the macroscopic deformation, has been studied. In the proposed experiment the study will be taken further by studying generations of intergranular stresses in textured material i.e. material with grains arranged in a preferred orientation. The results will not only help understand how intergranular stresses are generated in textured material but also will help improving the self consistent modelling of such material.
DOI: 10.5286/isis.e.rb1610530
title: Deformation mechanisms in Direct laser Deposited Inconel 718

description: The aerospace industry is adopting Material Addition (MA) processes, such as Direct LaserDeposition (DLD), for the original manufacture or repair of complex/high value components in alloys such as titanium and nickel superalloys. Tailoring of microstructure and texture to improve the performance of MA components is the key for the safe operation of an aero engine; however the current understanding of MA materials, in particular Ni alloys, is limited. Thus, the aim of the proposed experiments is to evaluate the evolution of internal strain in DLD processed IN718 alloys with different microstructures during compressive straining at room temperature, high temperatureand different loading directions. This data will be used to determine the active deformation mechanisms and how their relative activity changes under stress.
DOI: 10.5286/isis.e.rb1620118
title: Combining polarised neutrons and resonant x-rays to understand temperature-dependent interfacial proximity induced polarisation in platinum

description: Despite being a well-known phenomenon, the mechanism by which platinum gains a magnetic moment by proximity to a ferromagnetic (FM) thin film remains unknown. We aim to determine how the magnitude, and spatial extent, of proximity polarisation in Pt relates to the interface magnetisation in an adjacent CoFeTaB (CFTB) FM layer. Setting the Curie temperature of CFTB below room-temperature, we will measure PNR as a function of temperature where the CFTB layer is in either paramagnetic, or at various points in the ferromagnetic phase; each having different magnetisation. The magnetisation in CFTB at the interface will be extracted from fitting temperature dependent PNR measurements to obtain the magnetic scattering length density depth profile. Information on the proximity polarisation in Pt will be extracted from complementary X-ray resonant magnetic scattering measured on the same sample.
DOI: 10.5286/isis.e.rb1620156
title: muSR investigation of a possible spin-liquid state in 1T-TaS2

description: 1T-TaS2 is a layered material with many intriguing properties that are after four decades still sparking controversial discussions. Due to a charge gap, it has been long believed to be a Mott insulator, yet its magnetic ground state, which should be affected by the geometrical frustration of the corresponding spin lattice, remains largely unexplored. Here we propose a comprehensive muSR study to complement our NQR investigation, which is limited by extremely long 181Ta NQR relaxation times at low temperatures and lower sensitivity to small magnetic moments than muSR. This study should allow us to distinguish between the spin-liquid scenario and a state with small frozen/ordered magnetic moments.
DOI: 10.5286/isis.e.rb1620230
title: In Situ Measurement of the Spin Seebeck Effect

description: The spin Seebeck effect is a newly discovered phenomenon that if harnessed, could result in a significant improvement of the efficiency of thermoelectric energy generators. Spin polarised neutron reflectivity will provide us with complementary measurements that enable determination of the spin polarisation of the film as well as surface sensitive magnetic ordering and disorder at the interface. This is especially important as the influence of the interface (i.e. the magnetic proximity effect) is still not well understood. We propose using PNR in conjunction with a sample environment developed by Jos Cooper in order to investigate the magnetic structure (as a function of depth), whilst measuring the generated spin Seebeck voltage.
DOI: 10.5286/isis.e.rb1620416
title: The application of INS to investigate the methanol-to-gasoline reaction over ZSM-5

description: We propose to use MERLIN to measure INS from commercial zeolite catalyst samples extracted from a reactor in which they have been exposed to dimethylether for different lengths of time on stream. We have shown previously (RB1320360) that INS is the only form of vibrational spectroscopy able to observe the hydrocarbon species in the pores of the working catalyst. We wish now to establish how these species evolve throughout the catalyst lifetime. Dimethylether is the main component of the feed into the commercial MTG process over ZSM-5. The INS is a core component of a project funded by the EPSRC Catalysis Hub; samples extracted for INS will also be analysed by NMR, thermal analysis and electron microscopy. A complementary QENS application will investigate how diffusion within the catalyst pores is influenced by the presence of hydrocarbon deposits as the catalyst ages on stream.
DOI: 10.5286/isis.e.rb1620468
title: Proton diffusion in zirconate perovskites investigated by QENS

description: The growth in both global demand for energy and fossil-fuel related environmental issues drive research on alternative fuel sources. Solid oxide fuel cells, which can operate on a variety of hydrogenous fuels, have been proposed as a clean and economical solution for power generation. A performance bottleneck for many of these devices is the electrolyte; the thin membrane separating the electrodes, which allows ions to migrate while preventing electrons from doing so. We propose here a quasielastic neutron scattering (QENS) experiment to investigate the diffusion of hydrogen ions in a class of doped zirconium-based perovskite materials. By establishing the parameters governing diffusion in these and comparing the behaviour of materials with different dopants, we hope to gain valuable information for improving the performance of future electrolyte materials.
DOI: 10.5286/isis.e.rb1620471
title: Structure and phase transitions of Sr3Ru2O7

description: Sr3Ru2O7 is a layered Ruddlesden-Popper perovskite which displays intriguing behaviour at low temperatures and high magnetic field. It can be tuned close to a quantum critical point for magnetic field applied in the c-axis direction. On approach to the quantum critical point a novel phase appears with 'nematic' electron transport, the anisotropy of which can be switched by small in-plane field components. Detailed understanding of the electronic structure of Sr3Ru2O7 requires precise determination of details of the crystal structure, particularly the octahedral rotations.  In addition the high temperature phases of Sr3Ru2O7 have not been studied. Using the high resolution of HRPD we propose to map the thermal phase diagram of Sr3Ru2O7 in combined with detailed study of the crystal structure.
DOI: 10.5286/isis.e.rb1700079
title: Contour Method to Measure Radial Residual Stresses: Experimental validation

description: The contour method has been increasingly recognised as a powerful technique for measuring residual stresses. However, the conventional contour method is limited to performing flat cuts, which imposes important restrictions to the applicability of the technique, for example to complex structures. A new complex contour method has been developed at The Open University with the potential to provide a radical step change in the application of the technique to complex structures. The proposed 2-day experiment is designed to verify the accuracy of the novel contour method approach using non-planar cuts.
DOI: 10.5286/isis.e.rb1710066
title: Investigating the effect of nanoparticles on PBI self assembly

description: The generation of hydrogen from water using light could be a method of providing a clean fuel, which is clearly important for our growing energy needs. We are using perylene bisimides (PBIs) as photocatalyss for hydrogen evolution from water. For this process, we need to add a nanoparticle co-catalyst. We need to know whether the nanoparticles affects the assembly of the PBIs at high and low pH in order to design and optimise our systems. Currently, we have to assume that the particles have no effect on the assembly; if this is not true, we need to re-interpret our data.