cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1910605
title: Investigation of magnon dynamics of rare-earth garnet Ho3Fe5O12

description: Rare-earth Iron garnets (RE3Fe5O12) have been in the focus of active research for the last five decades due to their fascinating properties, such as large magnetostriction, magneto-optical effects and possible application in spintronic. These compounds, model system illustrating the Neel theory of ferrimagnetism, has complex magnetic properties and influence of this complexity is not well studied. Hence, elaborate study of spin wave propagation on these ferrimagnetic insulator is required to provide microscopic models of its complexity. The proposed compound Ho3Fe5O12 can be a potential candidate for such type of study because of large anisotropy and strong magnetic moment of Ho3+ ion. No definitive work relating to the detail of magnon mode structure of Ho3Fe5O12 exists so far. Hence we are proposing here to perform INS in MAPS spectrometer to find out all the existing spin-wave mode.
DOI: 10.17632/35b6b33jpb.1
title: Data for: Pathways for Low Carbon Nigeria in 2050 By Using NECAL2050

description: Nigeria Energy Calculator 2050 (NECAL2050) Model.
DOI: 10.5286/isis.e.rb1520010
title: Structure in "Microemulsions behaving badly"

description: An unusual set of systems, displaying key characteristics of microemulsions have been discovered using highly branched chain anionic surfactant stabilizers (Figure 1). Preliminary (and reproducible) SANS data point to the possibility that there are two droplet populations in these stable, transparent phase systems (Figure 1). However, there is no currently accepted model for microemulsion formation that allows for TWO DISTINCT DROPLET POPULATIONS in equilibrium. The purpose of this proposal is to investigate the structure of these intriguing ?microemulsion systems? and probe their odd behavior.
DOI: 10.5286/isis.e.rb1520037
title: Relationship between the formation of single chain particle from di-block copolymers and their conformation in dilute solutions

description: Single chain particles are resulted from the collapse of polymer chain in dilute solution. Their chemistry and morphology can be well controlled, thus serving as ideal model systems for applications like the directional assemble of colloidal particles into structures with lower symmetry. Esecially interesting is that when di-block copolymer is used, if only one block is collapsed, the the colloidal particle will have a dense head and a single tail. However, the production of such single chain particle is often at very low efficiency as the concentration of block copolymer has to be kept low to avoid inter-chain association. This study is to explore the relationship between comformation and single chain particle formation, thus to guide further effort in improving the production of single chain particles. With the ability to contrast match, SANS is ideal to achieve this goal.
DOI: 10.5286/isis.e.rb1520215
title: Spin dynamics in CP*-RE-COT

description: Single-Molecular Magnets (SMMs) provide access to the mesoscopic world. They possess slow magnetization relaxation due to an energy barrier induced by axial magnetic anisotropy, which makes them potential candidates for quantum computing, high-density storage and magnetic refrigeration. It is essential to improve blocking temperatures and control of quantum effects in SMMs for such applications. Zadrozny suggested that the magnetization relaxation in SMMs is governed by four processes (direct, quantum tunnelling (QT), Raman and Orbach), but they have never been thoroughly studied within a single material, or perhaps more importantly, how they differ has not been studied in a series of closely related materials. We propose to investigate the magnetisation fluctuations in two members of the CP*-RE-COT series at high temperatures to obtain a whole story of fluctuations in all materials.
DOI: 10.5286/isis.e.rb1520284
title: Cu-ion mobility and lattice dynamics in the liquid-like phase of Cu2Se

description: Thermoelectricity enables the conversion of waste heat into useful power, and it is becoming increasingly important for power recovery applications at high temperature, where thermoelectric performance is most efficient. Copper selenide has a simple crystal structure, and yet its thermal conductivity becomes comparable to that of a glass at temperatures above 800K, and this is very favourable for thermoelectric applications. The low thermal conductivity appears to be correlated with the onset of super-ionic diffusion of the copper ions above this temperature. We aim to test molecular dynamics simulations of the copper diffusion using quasi-elastic neutron scattering, and to relate this to changes in the lattice vibrations determined using inelastic neutron scattering, since these control the thermal conductivity.
DOI: 10.5286/isis.e.rb1520435
title: Inelastic Neutron Scattering study on new tetragonal compound Ce2PdGe3

description: Cerium-based Kondo lattice compounds have received great attention, owing mostly to the variety of exotic ground states that they exhibit (e.g., unconventional superconductivity, heavy fermion behavior, quantum criticality). Ce2PdGe3 undergoes two antiferromagnetic phase transitions at 10.7 K and 9.6 K and a ferromagnetic ordering at 2.25 K. The ordered ground state emerges from a lattice of Ce ions that are hybridized with the conduction electrons, as revealed by the enhanced electronic coefficient of the specific heat  50 mJ/mol-Ce-K2. Electronic structure calculations suggest that there is a significant f-electron weight in the density of states near the Fermi energy and that the Fermi surface includes sheets with distinct nesting vectors.  Since this strong electronic correlations has its origin in CEF effect it would be of utmost interest to study the CEF excitations using MARI.
DOI: 10.5286/isis.e.rb1520445
title: Inelastic neutron scattering study to understand the complex magnetic ordering of PrRu2M2B (M = Al and Ga)

description: In heavy fermion systems the competition between the RKKY interaction and the Kondo effect leads to a rich variety of phenomena, such as non-Fermi-liquid behavior, unusual magnetic ordering, and unconventional superconductivity. The strength of the hybridization between the f and conduction electrons is a key parameter to characterize heavy fermion systems. Our µSR spectra reveal coherent oscillation below magnetic ordering in CeRu2M2B (M = Al and Ga). INS studies reveal CEF excitation near 50 meV for CeRu2M2B.  For PrRu2Al2B antiferromagnetism (26 K) is followed by ferromagnetism (11 K) and for PrRu2Ga2B ferromagnetic transition is observed at 22 K. The evolution of ground state properties with chemical and applied pressure suggests that these phase diagrams may be connected in a Doniach-like picture. Our aim is to study the unusual ground state properties by means of INS study.
DOI: 10.5286/isis.e.rb1520492
title: Inelastic neutron scattering study on double perovskite Sr2TIrO6 (T = Ca, Sc, Y, Lu, Mg)

description: Recent observation of AFM transition at 1.3 K in Sr2YIrO6 with Ir in 5+ valence state has motivated research interests in the double perovskite Sr2TIrO6. Usually Ir5+ with a non-degenerate singlet ground state is nonmagnetic in nature. The unusual magnetism in Sr2YIrO6 arising from Ir5+ has been argued to result from the presence of strong crystal electric field (CEF) on the Ir sites. A breakdown of spin-orbit coupling (SOC) driven ground state as a result of delicate competition between the SOC, local exchange interactions and CEF is the key to the observed unusual magnetism of Ir5+ in Sr2YIrO6. Since the CEF is at the heart of magnetism in Sr2TIrO6, the investigation of CEF and magnetic excitations in these compounds using inelastic neutron scattering is highly desired for a better insight to the unusual magnetic ground state. We therefore propose to carry out INS study on Sr2TIrO6.
DOI: 10.5286/isis.e.rb1567505
title: µSR Study on the Electronic State in Heavily Doped Synthesis Diamond
DOI: 10.5286/isis.e.rb1600006
title: Texture Analysis in HCP and Cubic Materials for Validation of Spatially Resolved Ultrasonic Texture Measurements
DOI: 10.5286/isis.e.rb1820126
title: Cation coordination and oxide ion vacancy distribution in tetravalent substituted BIMEVOXes

description: Oxide ion conductors based on bismuth oxide based have recently been demonstrated as viable alternatives to traditional electrolytes for intermediate temperature solid oxide fuel cells. The BIMEVOX family of solid electrolytes based on substitution of V and/or Bi in Bi4V2O11-delta, exhibit some of the highest known oxide ion conductivities at low and intermediate temperature. We have previously predicted that in the Ge4+ and Sn4+ substituted BIMEVOXes, these cations adopt different coordination geometries, which leads to different solid solution limits and phase behaviour. Using reverse Monte Carlo analysis of total neutron and X-ray scattering we propose to examine differences in the cation coordination and oxide ion vacancy distribution in these BIMEVOX systems and compare these with the theoretical predictions.
DOI: 10.5286/isis.e.rb1910289
title: Magnetism and first order phase transition of Ni42Co8Mn38Sb12: Neutron diffraction study

description: Heusler alloys have gained important place in condensed matter physics due to their versatile functional properties such as large magnetoresistance, giant magnetocaloric effect, spontaneous exchange bias, spintronics etc. In particular, giant magnetocaloric effect was reported in systems with magneto-structural coupling, resulting from the first order magnetic phase transition. So as to strengthen the understanding of functional properties, it is mandatory to understand the magnetic structure of the compounds. Neutron diffraction characterization is an indispensable tool to understand the magnetic structure of the compounds by disclosing the individual magnetic contribution of the elements and to determine the type of universality class by extracting critical exponent. Presently, we propose to measure temperature-dependent neutron diffraction of one such compound Ni42Co8Mn38Sb12.
DOI: 10.5286/isis.e.rb1910406
title: Exploring grain - ice mantle interactions and dynamics for the extraterrestrial context

description: Polycyclic aromatic hydrocarbons (PAHs), a wide class of organic molecules with multiply fused aromatic rings, are ubiquitous in the interstellar medium. In the condensed phase they are expected as precursors to small graphitic grains or condensation nuclei for icy grain mantles, from which they can be transformed into more complex organic and bio-relevant molecules. However, the paths for these processes remain relatively unexplored and little is known of the dynamic behaviour around these carbonaceous, icy grains.From the background of our previous studies of the dynamics of adsorbed PAHs on graphitic surfaces, we propose to explore the pre-melting dynamics of water ice and PAH/water ice mixtures on graphite as a model of icy grains, specifically, the small PAH, fluoranthene, which is well characterised alone and of a symmetry rendering it a particularly relevant astrochemical model.
DOI: 10.5286/isis.e.rb1910424
title: Molecular dynamics in the Metal-Organic Framework [CH3NH3][Co(COOH)3]

description: Magnetic hybrid organic-inorganic Perovskites have attracted much attention lately as they potentially show a magneto-electric coupling, thanks to the strong interaction between the framework and the molecular host. In particular, a diffraction study at zero-field of CH3NH3Co(COOH)3 shows a structural transition around 90 K concomitant with an antiferroelectric behaviour and a magnetic order below 15 K.We would like to study the molecular dynamics through the antiferroelectric and magnetic transitions by performing high-resolution quasi-elastic neutron scattering. In particular, the molecular cations should be responsible for the antiferroelectric transition and may be coupled to the magnetic order via a possible magneto-electric coupling.
DOI: 10.5286/isis.e.rb1910436
title: Texture evolution of an AA7075_O alloy during cold radial forging

description: Radial forging is an open-die forging process utilizing radially moving dies for producing of cylindrical/tubular components with different internal and external profiles. The process has good reliability to produce high integrity forgings with tight tolerance, smooth surface, improved mechanical properties at high production rates (relatively) and low cost. These bring extensive application potentials in aerospace, automotive, and oil and gas industries. However, establishing the radial forging procedure is still an expensive and time-consuming process based on trial and error, due to the lack understanding of complex deformation characteristics leading to several type of defects in the components. this work aims to study material flow during cold radial forging process and study crystallographic texture evolution during cold radial forging operation.
DOI: 10.5286/isis.e.rb1910592
title: High resolution measurement of mode Grueneisen parameters in the negative thermal expansion material ZrW2O8

description: ZrW2O8 is the classic example of a material exhibiting negative thermal expansion (NTE), i.e. lattice shrinkage on warming. The origin of this behaviour has been controversial for a long time, but is widely believed to be intimately linked to the lattice dynamics. Recent ab-inito studies have suggested that there is no single phonon mode that is responsible for the NTE, rather a collection of low energy modes all contribute. These same ab-initio studies have been used to explain the origin of negative hydration expansion (lattice shrinkage on intercalation of water) in ZrW2O8. The aim of this proposal is to verify the calculations directly using single crystal inelastic neutron scattering to measure how all of the low energy modes shift as a function of temperature, a key prediction of the theoretical work.
DOI: 10.5286/isis.e.rb1910623
title: Neutron Diffraction study on two novel topological Dirac semimetal candidates EuMnBi2 and EuMnSbBi

description: Dirac fermions with linear energy dispersion with momentum space have been of current interest for spintronic applications because a variety of quantum transport phenomena manifest themselves in an external magnetic field due to extremely high mobility. Layered compound EuMnX2 (X=Bi, Sb) appears to provide an ideal arena to reveal the interplay between Dirac fermions and ordered magnetic moments. However, magnetic structure, which is vital to understand this interplay, has not been investigated so far through neutron diffraction experiment. This proposal is to serve as the first proposal to study the magnetic structures of two single crystal compound EuMnBi2 and EuMnSbBi.
DOI: 10.5286/isis.e.rb1520022
title: Spin orders in CaxMn2-xFeReO6 double perovskites

description: New manganese-based double perovskites Mn2-xCaxFeReO6 have been synthesised at high pressure. Mn2FeReO6 has spin-active cations at all sites; S = 5/2 Mn2+, S = 5/2 Fe3+ and S = 1 Re5+  and has TC = 520 K. Very high magnetisations are observed up to M = 5.0 BM/f.u. for Mn2FeReO6 (the previous record in double perovskite ferrimagnets was 4.3 BM/f.u.) Mn2FeReO6 also has novel MR properties. 5 days of  WISH beamtime are requested;- 2 days for zero field studies of x = 0.5 and 1.5 between 10 and 300 K, to determine crystal and magnetic structures. -3 days for high field experiments on Mn2FeReO6 to explore the three spin ordering regimes discovered in initial neutron experiments. 50 mg polycrystalline samples will be used. The Mn2FeReO6 sample will be pelletised to minimise field reorientation of grains. Results will be essential to help understand these new spintronic materials.
DOI: 10.5286/isis.e.rb1520025
title: Spin, charge and orbital ordering in the new LiMn7O12 perovskite

description: ABO3 perovskite oxides with Mn on A and B sites are of fundamental interest due tophenomena that emerge from the coupling of charge, orbital and spin orders. Wehave synthesized a new compound, LiMn7O12 with Li:Mn 1:3 ordering in the A-site,i.e. (Li Mn3+ 3)(Mn3+ 2 Mn4+ 2)O12. Magnetisation measurements reveal a probablecharge and orbital ordering transition at 250 K, and a spin ordering transition at 50 K.Variable temperature neutron powder diffraction studies are requested to determine the spin, charge and Mn3+ orbital (Jahn-Teller) orders in the structure ofLiMn7O12 and their evolution between 10 and 300 K.
DOI: 10.5286/isis.e.rb1520138
title: Magnetic structure of a novel quantum magnet

description: Preliminary bulk measurements show that Ba(TiO)Cu4(PO4)4 is a potentially exciting candidate for studies of low-dimensional magnetism. However, currently relatively little is known about the ground state magnetic properties of this system. In this proposal we wish to determine the base-temperature magnetic structure of this newly synthesised compound.
DOI: 10.5286/isis.e.rb1520169
title: Order and dynamics in S=1 Ni-based molecular magnets

description: Recent progress in the field of molecular magnetism has shown the clear potential for gaining control over the structural building blocks of molecular materials in order to engineer desirable magnetic properties. Low-dimensional Ni(II)-based S=1 antiferromagnets continue to draw much interest across the field of magnetism, but are generally quite poorly understood. We now wish to study three new Ni-based molecular antiferromagnets, which have been recently synthesised and which each show interesting properties with potential for tunability. In each case, we seek to investigate the nature of the magnetic ordering transition and make a study of the dynamics of the system in the temperature regime where the low-dimensional behaviour is expected.
DOI: 10.5286/isis.e.rb1520173
title: Oxygen Positional Disorder in the "Empty" Tetragonal Tungsten Bronze Ba4La0.67Nb10O30

description: Ferroelectric tetragonal tungsten bronze oxides (TTBs) have been extensively studied for their application dielectric and non-linear optical devices. TTBs often exhibit structural (incommensurate) modulations which partially disrupt the long-range ferroelectric ordering and lead to relaxor behaviour. Recently we discovered a novel polar, commensurate TTB, Ba4La0.67Nb10O30, which displays relaxor behaviour. Electron diffraction shows that the oxygen positions are completely disordered; these local variations disrupt long range polar ordering resulting in a lack of macroscopic (ferroelectric) polarisation. Conventional diffraction analysis is insensitive to these local variations and so the aim of the current proposal is to probe the local structural variations as the material progresses from the relaxor to non-ferroelectric phase using total neutron scattering methods.
DOI: 10.5286/isis.e.rb1520244
title: Investigation of bilinear magnetoelectric effect in magnetic field-induced multiferroic phase of alpha-NaFeO2

description: We propose to perform a neutron diffraction experiment under magnetic fields using a single crystal sample of multiferroic alpha-NaFeO2 on WISH beamline. Recently, we have suggested a novel mechanism for the higher-order bilinear magnetoelectric effect in this compound from our powder neutron diffraction measurements [N. Terada et al, PRB 89 184421 (2014)]. The mechanism implies a field-induced symmetry-lowering of the incommensurate propagation vector, which is from a line of symmetry to a general point. The mechanism is very general and is relevant to all classes of multiferroics. To unambiguously confirm the mechanism, a single crystal experiment is necessary. Recently, Prof. Sato?s group has succeeded in growing high-quality alpha-NaFeO2 single crystals. In this study, we propose to directly explore the effect of the magnetic field on the incommensurate propagation vectctor.
DOI: 10.5286/isis.e.rb1520317
title: Quantification of residual stresses in SA508 steel welds produced using laser and laser-hot wire welding processes

description: Residual stresses are detrimental to performance of large reactor components, and knowledge of the stress state in the manufactured components is necessary in order to carry out structural integrity assessments. Post-weld heat treatment restores toughness in the vicinity of welds and, to a lesser extent, relieves residual stresses. However, some level of residual stress remains. In order to reduce the residual stresses, we can choose a welding process in which the extent of the regions subject to high-level tensile stresses is minimised. It is postulated that laser-based processes will achieve significant reductions in the residual stresses in comparison to conventional arc welding and electron beam welding processes. The focus of this proposal is to explore the residual stress developments in these laser welds.
DOI: 10.5286/isis.e.rb1520322
title: Investigation of Jahn-Teller assisted polaron collapse beyond the percolation threshold in a colossal magneto-resistance manganite

description: Polaron-mediated colossal magneto-resistance (CMR) was predicted decades ago but never been experimentally  established unambigously, despite the 'universal' existence of polarons in perovskite manganites. The CMR effects observed so far appear to be cause by percolative conducting path formation in magnetic field. Polarons dominate the physics on a different spatial scale to percolative domains; the resultant CMR effect may happen on a different energy scale as well. Since adding a second tunable state to a storage device increases its capacity drastically, a separate polaron-mediated CMR state is greatly desired. By carefully tailoring our material, for the first time we managed to distinguish the polaron collapse at a field much higher than the percolative threshold. We ask for time on WISH to verify the role of Jahn-Teller distortion in polaron-mediated CMR.
DOI: 10.5286/isis.e.rb1520495
title: Using negative muons as a non-destructive probe of biomaterials

description: Expanding the provision of tools for trace element analysis of biomaterials is very attractive, especially where the tools can be used non-destructively and permit analysis throughout an intact sample volume. Some elements are notoriously difficult to analyse in biological material such as soft tissue, due to a lack of specificity (e.g. histological staining to distinguish copper and zinc), sensitivity (e.g. to trace metals such as manganese), or where elements are lost during tissue preparation and sectioning. In recent years, synchrotron micro- and nano-focussed X-ray fluorescence (XRF) mapping has been optimised as a sensitive, element-specific, non-destructive alternative to laser-ablation ICP-MS mapping, and this has been applied in many contexts including the dysregulation of transition metal metabolism in neurodegenerative disorders such as Alzheimer?s and Parkinson?s disease.
DOI: 10.5286/isis.e.rb1820240
title: The mechanism of lipid transport in Gram-negative bacteria

description: The bacterial cell envelope is one of the best targets for antimicrobial development. It is this envelope that harbours the instruments of microbial warfare, preventing its formation will therefore stop infection. This proposal focuses on one aspect of envelope formation, the movement of lipids between the membranes of the double membrane cell envelope. Until recently how lipids were transported between the membranes remained unknown,  however, the Mla pathway, has been identified and provides the first evidence of a lipid transport pathway in gram-negative bacteria. However, how this pathway functions remains elusive. The aim of this proposal is to tackle these issues. Neutron reflectometry provides the ideal tool for monitoring the movement of lipids to and from the membrane and will provide vital information about how the Mla pathway functions.