cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1910113
title: µSR study of new non-centrosymmetric superconductor Re5.5Ta

description: In this proposal, we want to explore the superconducting properties of noncentrosymmetric superconductors Re5.5Ta along with pure Re (99.99%) to understand the role of Re in Re6X and Re3X series compounds.
DOI: 10.5286/isis.e.rb1910133
title: Investigation of crystal and magnetic structures of three polymorphs of Fe2WO6 iron tungstate.

description: Iron tungstate Fe2WO6 attracts increasing interest in two areas of applications due to its photoelectrochemical behaviour. Fe2WO6 can act either as a photocatalyst for degradation of environmental pollutants or as a photoanode for water oxidation in tandem devices. Recently, some of its magneto-dielectric properties have been reported but its magnetic and electric properties remain nebulous. Indeed, Fe2WO6 iron tungstate exists as three polymorphs and their 3D structures are induced by the cationic ordering. We obtained a complete set of the three polymorphs as single phase products for the first time. By the use of neutron diffraction (10-300 K), we aim to complete the structural models and determine the impact of the structure and cation ordering on the magnetic properties of the three polymorphs vs temperature.
DOI: 10.5286/isis.e.rb1910148
title: Cation-Exchanged  Layered Polar Perovskite Oxides (Structural)

description: Multiferroic materials - those which exhibit spontaneous and switchable electrical and magnetic polarizations - have a wide range of applications. However preparing new magnetoelectric materials is challenging because ferroelectric and ferromagnetic properties are contraindicated. We have been working of a strategy of introducing magnetic behaviour to existing ferroelectric materials via topochemical cation exchange. Specifically, we are exploring the cation exchange chemistry of polar Dion-Jacobson and Ruddlesden-Popper oxide and oxynitride phases to see if we can induce ferromagnetic behaviour whilst retaining the existing ferroelectric behaviour. We propose to collect high resolution neutron powder diffraction data from these exchanged phases, so we can determine their complex structural distortions, and thus determine if they retain their ferroelectric behaviour on cation exchange.
DOI: 10.5286/isis.e.rb1910185
title: Unveiling the role of phonons in reaching very high blocking temperatures in Dy-based single-molecule magnets

description: One of the main goals of the research in Molecular Magnetism is to increase the blocking temperature TB of Single-Molecule Magnets (SMMs). A significant breakthrough was achieved with the dysprosocenium compound and its record TB = 60 K. Recent results on similar Dy-based compounds showed a clear correlation between TB and Raman relaxation. Thus, a deeper insight into SMMs phonon-induced relaxation dynamics is required, but very few experimental information on phonons is available. Having already successfully measured the phonon density of states (DOS) of the dysprosocenium compound, we propose using MERLIN to measure the phonon DOS of two other Dy-based molecules, displaying much lower TB despite still having strong magnetic anisotropy. This systematic study on phonons in SMMs will allow us to correlate them with TB, in order to identify the real ingredients behind high-TB compounds.
DOI: 10.5286/isis.e.rb1910211
title: Spin correlations and order in titanates exhibiting spin Jahn-Teller antiferromagnetism

description: The spin Jahn-Teller effect stabilises 3D magnetic order in an otherwise frustrated system via magnetoelastic coupling, spontaneously at the magnetic phase transition. Examples are rare, and limited to crystals of high symmetry (e.g. spinel). We have shown that CoTi2O5, a low symmetry crystal, also exhibits spin Jahn-Teller antiferromagnetism. Here, low dimensional magnetism persists above the Neel temperature, allowing, in principle, for the 3D antiferromagnetic order to be switched on and off by applied strain  a novel material functionality of interest in the field of spintronics and oxide electronics. We propose a neutron scattering experiment to characterise the key low dimensional order, as well as determine the magnetic character of an isostructural material, FeTi2O5, which may prove to be a more promising candidate for inclusion in a spin Jahn-Teller device.
DOI: 10.5286/isis.e.rb1600045
title: Structure and dynamics of nano-confined supercooled water studied by Deep Inelastic Neutron Scattering
DOI: 10.5286/isis.e.rb1610110
title: Reconstituted lipoprotein particles - Implications of structure and dynamics on atherosclerosis development.

description: Neutron scattering will allow to advance the understanding of lipoprotein behavior in solution and at the interface of relevant biological interfaces. Here we focus on HDL fractions extracted from blood and reconstituted with given apolipoproteins. Their structure and ability to exchange lipids is likely to be dependent on the apolipoprotein isoform. Here we will focus on both the structure and lipid exchange dynamics of these particles using as a reference model cellular membranes made of invisible phosphatidylcholine.
DOI: 10.5286/isis.e.rb1610121
title: The Second Critical Point and Widom line of supercooled confined water

description: In 1992 P. Poole and coworkers have proposed the existence of two water polymorphs below its homogenous nucleation temperature. These are separated by a coexistence line ending in a second critical point. From this point a line of maxima of the correlation lengths (Widom line) originates. Experimental tests of this model have been performed in confined water, that can be easily supercooled. No unambiguous evidence for the existence of the Widom line has been so far published. NIMROD can contribute relevant insights into the vivid debate present in the literature. To this aim, we propose to perform a NDIS experiment on water confined in MCM41 substrates, with different confining sizes, along a temperature path from ambient down to 210 K, at ambient pressure. NIMROD is well suited to evidence at the same time critical fluctuations and/or crystallization.
DOI: 10.5286/isis.e.rb1610315
title: Research of the microstructure of three component mixture with anomalous behaviour

description: Solvents are integral part of the world and so many charge transfer processes take place in a solutions. Unfortunately, not much is known about the microstructure of solvents and solvent mixtures. It is usually assumed that when a mixture seems homogeneous in macro world the same applies for microstructure and reaction environment. Some binary solvent systems have been studied by small-angle neutron scattering (SANS) methods and it has been shown that microheterogenity can occur in some multicomponent solvent systems. Observed heterogeneous clusters show that the solvent molecules are not evenly distributed and the microenvironment around a single molecule can be different from what is usually assumed. Only a few tertiary systems have been studied and our research focuses on the structure of tertiary system consisting of 1,4-dioxane, naphthalene and water.
DOI: 10.5286/isis.e.rb1610368
title: Smart dendrimersomes for biosensing and triggered delivery

description: Dendrimersomes are an exciting new class of vesicles, comprising bilayers of dendrimer molecules that can be engineered to have sensitivity to e.g. changes in pH and enzymes. However, in order to find applications in triggered drug delivery and biosensing, their fine structure and changes to self-assembly must first be characterised. We propose a series of experiments to characterise the fine structure of a model dendrimersome and its response to changes in ionic strength and dilution. We then use contrast matching to investigate the effect of acidic pH and the enzyme sphingomyelinase on dendrimersomes engineered to respond to these two triggers respectively. Dendrimersomes sensitive to these triggers have huge potential in stimuli-responsive treatment of cancer, Alzheimers disease and atherosclerosis.This experiment will be the first SANS study of dendrimersomes.
DOI: 10.5286/isis.e.rb1610416
title: Local and long-range ordering in concentrated nanotube solutions

description: Manipulating nanoparticles in liquids is crucial for their scalable implementation in future technologies. For example, such liquids can be used like paint to create uniform films over large areas at low costs. We have developed a method to dissolve the highly promising nanoparticles known as 'carbon nanotubes'. These minute tubes, 10,000th the size of a human hair, promise an array of important future applications from flat screens to smart textiles. In this experiment, we will use neutron scattering to measure the arrangement of the solvent molecules around the nanotubes in our solutions, in order to understand how they dissolve. We will also investigate predictions that the nanotubes will line up at high concentrations. The knowledge gained will permit the optimisation of these liquids for their use in creating future nanotube-based technologies.
DOI: 10.5286/isis.e.rb1610533
title: The feasibility of boron isotopic substitution
DOI: 10.5286/isis.e.rb1710160
title: SANS and SESANS an ideal combination for Photonic materials

description: In this proposal we request time to characterise some novel colloidal particles that cannot be characterised with other approaches.  These are believed to be raspberry particles which have a large central core with a layer of particles on the surface. Significantly these appear to have unexpected colloidal stability. In this proposal we aim to characterise the individual particles. This will be followed by a subsequent proposal to assess the inter-colloid interactions at higher number density. Due to the large size of the colloids these cannot readily be assess by conventional SANS alone and hence we propose to combine SANS with SESANS which can access the longer length scales required.
DOI: 10.5286/isis.e.rb1720047
title: INS studies of the interaction of propene with ZSM-5

description: Fluidised Catalytic Cracking (FCC) units are one of the major conversion units in modern petrochemical refineries. ZSM-5 additives 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 ZSM-5 reacts with propene.
DOI: 10.5286/isis.e.rb1720112
title: Magnetic order in the triplet superconductor Sr2RuO4

description: Sr2RuO4 is an oxide metal which becomes superconducting at 1.5 K.  In conventional superconductors, the electron (Cooper) pairs responsible for superconductivity have zero angular momentum, and zero net spin. In contrast, Sr2RuO4 is highly  unconventional because the electrons form Cooper pairs with an angular momentum L=1. In addition, the spins of the paired electrons form a triplet spin state.  Soon after the discovery of superconductivity in Sr2RuO4, muon spin resonance showed that additional magnetic moments appears on entering the superconducting state. The exact symmetry of the superconducting state of Sr2RuO4 is still hotly debated, but it seems impossible to reconcile the existence of these moments directly with the superconductivity. We therefore propose to search directly for spin density wave order. The presence of this type of order would explain this long standing mystery.
DOI: 10.5286/isis.e.rb1720303
title: Local magnetism in graphene / transition metal oxide nanocomposites

description: Properties of graphene that make it an important material are its exceptionally high conductivity, massless fermions and a high velocity of electrons near the Dirac points. Composites of graphene and transition metal oxides (TMOs) are being investigated as possible supercapacitor storage materials, and graphene may also find use in spintronic devices because of its large electron spin diffusion length. In this proposal we investigate the local magnetism in graphene - magnetic TMO composites, the TMOs being nanoscale antiferromagnetic insulators, the surface of their nanostructures having a net magnetic moment. uSR will be used to probe these materials to look for magnetic coupling between the graphene and the TMO moments. Measurements will be made when at temperatures low enough to observe the impact of graphene on magnetic moment freezing in the TMOs and when applying magnetic fields.
DOI: 10.5286/isis.e.rb1720484
title: Thermal equations of state for kyanite, andalusite and sillimanite

description: The three Al-silicate polymorphs, kyanite, andalusite and sillimanite, are well-known geological markers used to determine the extent of P- and T-induced metamorphism experienced by rocks in the Earth's crust. Despite extensive study of their thermodynamic properties, there has only been one study (of kyanite published in 2016) as a function of pressure AND temperature. The compressibilities of andalusite and sillimanite have only ever been characterised at room temperature. In a recent HRPD study, I found that the latter two minerals exhibit negative linear thermal expansion below room temperature, which one would expect to translate into anomalous linear compressibility. In order to study this further I propose the first systematic PVT study of all three polymorphs using the Paris-Edinburgh press on PEARL.
DOI: 10.5286/isis.e.rb1720504
title: SESANS investigation of structural colour in polar bear hair

description: Structural colour arises not from dyes or pigments, but from light scattering off of the inner geometry of the material itself.  This offers greater stability than standard absorbing techniques, as there is no chemical pigment to break down and fade.  The occurrence of structural colour in biological materials has been well studied and bio-mimicry of the structures provide multiple industrial applications.While the name structural colour implies visible light, the same concept can be extended into the infra-red.  Electron microscopy has shown the presence of micron scale structures within the hair of a polar bear.  This places the "colour" near the peak of the polar bear's own thermal radiation, creating an efficient insulator.  Recent upgrades to the SESANS apparatus on the Larmor beam-line make this structure accessible to scattering methods for the first time.
DOI: 10.5286/isis.e.rb1720516
title: Temperature dependence of the diffuse nuclear and magnetic scattering in CsNiCl3. SXD data for modelling

description: We propose to collect data on SXD with a large crystal of CsNiCl3.  As shown, this will allow us to study the nuclear diffuse scattering originating for the phonons scattering around the Bragg points.  The date will be compared with compare with simulations of the phonon diffuse scattering based on CASTEP calculations.At low temperatures we will also observe diffuse magnetic scattering which will be compared with molecular field modelling.
DOI: 10.5286/isis.e.rb1768011
title: Probing re-entrant glassy state in spin chain compound Sm2BaNiO5 using µ-SR studies

description: We are currently investigating Haldane spin-chain compounds [PRB 2017] of the type R2BaNiO5 (R = rare earth) using bulk measurements and have found the multifunctional properties such as re-entrant glassy behaviour, magnetoelectric coupling, multiferroic ordering. To understand the nature of the magnetic ground state, we proposed here to carry out μSR experiment on Sm2BaNiO5. This study on Sm-based material is essential, because the neutron scattering study will be difficult due to high absorption cross-section of Sm. We want to measure Zero-Field (ZF) and Longitudinal-Field (LF) μSR down to 1.5 K from 100 K. The proposed μSR study will be important to establish the re-entrant magnetic glassy state in this compound.
DOI: 10.5286/isis.e.rb1810193
title: muSR investigation to probe spin fluctuations in the ordered phase of (Nd1-xCax)2Ir2O7 and Y2Ir2O7

description: From our current results of (Nd1-xCax)2Ir2O7, the internal field at 1.5 K increases with increasing the hole doping, the relaxation rate at 50 K increases with increasing the external field and shows a peak ~2.5 T at 15 K. The spin fluctuation shows the Redfield-like behavior at 1.5 K. In 3.6 T with x=0, a peak in the relaxation rate was observed ~50 K. Even in the case of x=0.07 in which only the ordering of Nd moments are expected below 1 K, we can still see a clear peak ~15 K. Those means Nd and/or Ir have low-lying spin fluctuations. We cannot catch up any fixed scheme to discuss it due to fewer data points. We would like to suggest more measurements in (Nd1-xCax)2Ir2O7 (x=0 at 5 K, 10 K, 25 K, 35 K, 100 K) and other Ca-doped samples (x=0.05, 0.07, 0.10, 0.20) to see a whole view of low-lying spin fluctuations and discuss the 4f-5d exchange interaction by measuring Y2Ir2O7.
DOI: 10.5286/isis.e.rb1810246
title: The Impact of Multivalent Counterions on the Surface Adsorption of the Anionic Alkyloxyethylene Sulfate and Sodium Dodecyl Sulfate Mixtures

description: Surface multilayer formation provides great potential for the tuning and optimising surface wetting properties and applications such as lubrication, drug delivery. Normally surfactants form a single layer at water interface. Under certain conditions, surfactants may form multilayer. The addition of electrolyte especial higher valence counterions such as Aluminium have been shown to generate significant structure and promote adsorption. SDS is a common impurity in SLES and yet its interaction with Calcium or Aluminium in the presence of SLES to our knowledge has not been studied. Here we propose to investigate the impact of multivalent countions on the adsorption and assembly of SLES/SDS mixtures at the air water interface by neutron reflectivity.
DOI: 10.5286/isis.e.rb1810512
title: Monitoring the formation of surface-enriched PbI2 in atmospherically treated perovskite films using neutron reflectivity

description: Metal halide perovskites have enabled remarkable advancements in low-cost, high-performance optoelectronics, however their performance potential is restricted by an incomplete understanding of structural and compositional changes that take place due to sample surface passivation treatments in different environments. Using neutron reflectivity we will develop this research area by measuring in-situ the kinetics of compositional changes at the surface of perovskite films during sample exposure to a range of atmospheres, correlating the results with simultaneous photoluminescence measurements that provide a measure of semiconductor film quality. This state-of-the-art study will be used alongside complementary studies at Cambridge and our collaborators to construct new structure-property relationships that will be used to advance perovskites as a class of semiconductor that functions at its
DOI: 10.5286/isis.e.rb1810607
title: Architecture of lipid-protein nanoglobules in velvet worm prey capture slime

description: Fiber fabrication in animals is an important inspiration source for polymeric materials. Velvet worm prey capture slime represents a unique way of fiber fabrication by using monodisperse lipid-protein nanoglobules as storage units, which reversibly self-assemble after mechanical impact into stiff polymeric fibers. The primary component of the tensile fiber are proteins. With the planned experiment we aim at the characterisation by small-angle neutron scattering of the internal architecture of the nanoglobules and of their reorganization into fibers and back.
DOI: 10.5286/isis.e.rb1820084
title: In-situ study of mechanism for magnetovolume effect in Cr-Fe alloys

description: Negative thermal expansion (NTE) materials, the volume of a material abnormally contract with the increase of temperature, is closed related to the magnetovolume effect (MVE) in magnetic materials. However, due to the limited knowledge of the mechanism for MVE, the progress of searching for new NTE metallic materials with excellent performance is quite slow. Here, we found enhanced MVE and abnormal thermal expansion in cubic Cr with little Fe substitutions for Cr. Due to the simple crystal structure and binary composition, Cr-Fe alloys is a favorable example to investigate the mechanism of MVE and NTE for many other metallic materials. In this study, we intend to determine the detailed magnetic and crystal structure for Cr-Fe alloy by long-wave length in-situ neutron powder diffraction experiments, which could help to give new insight into the mechanism of MVE in metallic materials.
DOI: 10.5286/isis.e.rb1820319
title: Neutron reflectivity studies of the interaction between a novel antimicrobial agent and biomimetic lipid monolayers

description: A Unilever proprietary technology has been shown to inhibit biofilm growth and development, and is also found to possess antimicrobial activity, effective both as a broad-spectrum antibacterial and as an antifungal agent. This is unusual and requires both specific and holistic understanding of the agents mode of action at a molecular level. In the studies proposed here (performed using the technique of neutron reflectivity), we aim to determine the effect of this potential new drug on model fungal, bacterial and mammalian cell membranes. We hope then to elucidate the key common factors which render the technology effective in controlling biofilm formation as well as exploring the its impact on different infective organisms.
DOI: 10.5286/isis.e.rb1820489
title: Solvation structure of sodium ions and hexa-fluorophosphate ions in organic carbonate electrolytes for sodium ion batteries.

description: Here we propose to study the local structure of sodium in standard organic carbonate electrolytes for sodium ion batteries. Three different electrolytes are chosen to study; a flexible linear carbonate diethyl carbonate, a more rigid cyclic carbonate propylene carbonate and the commercially most common a mixed cyclic and linear carbonate solution. we hope to understand how different molecular structure will change the local structure around the sodium and how this will effect the probability of forming ion pairs in the solution.
DOI: 10.5286/isis.e.rb1820566
title: Phonon dynamics in liquid gallium

description: We propose to measure the inelastic scattering S(Q,E) maps from gallium in its liquid phases across a wide range of temperatures. This proposal is based on a new prediction for the existence of transverse acoustic modes that show a gap in wave vector at zero energy. Performing an inelastic neutron scattering measurement at ISIS will give us a much richer data set than possible from only x-ray scattering, including obtaining data at higher values of Q, and enable us to use our new analysis tools to relate the observations with the dynamics of local atomic arrangements.  We expect this work coupled with the data from inelastic x-ray scattering to lead to nothing short of a revolution in how we understand the differences between liquid and crystalline phases.
DOI: 10.5286/isis.e.rb1820616
title: How low can you go?

description: Elemental analysis is a method which can be used to determine the composition of samples. Anon-destructive approach that can analyse the bulk of the sample can be performed usingnegative muons. This technique is desirable for valuable items in a variety of fields, fromengineering to archaeological studies. In this proposal we intend to determine the limits of the measurements.