cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1710302
title: Structural analysis of Kitaev spin liquid candidate beta-Li2IrO3 under pressure

description: The theoretical predication of Kitaev spin liquid in honeycomb iridates triggered tremendous interests. We recently discovered a new candidate material, beta-Li2IrO3 with a 3D analogue of honeycomb lattice dubbed hyperhoneycomb lattice. beta-Li2IrO3 in fact undergoes a magnetic ordering below 40 K. Interestingly, by an application of pressure above 2 GPa, the magnetic order was suppressed and NMR measurements suggest a spin liquid state. We also observed a pressure-induced structural transition around 4 GPa at room temperature by x-ray diffraction, but the structure of high-pressure phase remains elusive. We propose to perform powder neutron diffraction experiment under pressure up to 7.5 GPa on PEARL in order to elucidate the key structural difference between the magnetically ordered and spin liquid states, and also to determine the crystal structure of high-pressure phase.
DOI: 10.5517/ccdc.csd.cc21mysf
title: CCDC 1896015: Experimental Crystal Structure Determination

description: Related Article: Erwann le Coz, Hanieh Roueindeji, Vincent Dorcet, Thierry Roisnel, Jean-François Carpentier, Yann Sarazin|2019|Dalton Trans.|48|5500|doi:10.1039/C9DT00771G
description: An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
DOI: 10.5286/isis.e.rb1410266
title: Tracking how the spin cycloid in BFO evolves with electric field and temperature

description: AFM order in BFO was first detected by neutron diffraction and was classified as Type G. However, the spins are not perfectly antiparallel; there is a spatial-modulated spin cycloidal structure with an incommensurate period of 64nm. This proposal aims to answer the following questions:1. How does the cycloid wavelength evolve with temperature field?2. Is there a reorientation of the cycloid direction when the electric field is applied? 3. Is the degeneracy between the different crystallographic orientations of the cycloid vector lifted? 4. Does the tuning of the spin order offer a way to achieve strong magnetoelectric coupling?Answers will be found by performing a GiSANS experiment on a [111] oriented BFO, to measure how the cycloid length scale changes under and applied electric field and temperature.
DOI: 10.5286/isis.e.rb1500014
title: In-situ mechanistic studies of hydrogen storage reactions in lithium amide halide systems.
DOI: 10.5286/isis.e.rb1510171
title: Ordering of water molecules in water/amino acid mixtures

description: The obvious role played by water dynamics in the biological movements and reactions has stimulated huge experimental efforts during last years. However, biological materials are in general very complex systems, showing many degrees of freedom. Therefore, investigations on water dynamics in more simple systems - but showing similarities with biological materials - can illuminate the way to unravel these questions. In a recent experiment we have investigated the dynamics of water in amino acid solutions (lysine/water). The results are very promising but we need to analyze the structure of water molecules in the first hydration shell and also in those loosely bounded in the lysine solution. We propose to perform sandals experiments in order to learn about the ordering of water molecules about lysine.
DOI: 10.5286/isis.e.rb1510186
title: Exchange kinetics of complex coacervates core micelles

description: Coacervates have been studied for a long time for their unusual properties: they are dense networks of charged polymers that are soluble in water. Instead of flocculating when exposed to high salt concentrations, they dissolve. They are fully permeable to water, yet they are capable of strongly binding heavy metals or large (bio-)molecules , making them useful for wastewater purification, coatings, and as drug carriers. By modifying them to form micelles, the micelle cores become small coacervate networks; Complex Coacervate Core Micelles (C3Ms). Unlike gels, they are dispersed into solution easily. The structure of C3Ms is quite well known, but exchange kinetics of the polymers between micelles is nearly unknown. Understanding these kinetics by direct observation with SANS is important to assess the stability of these micelles for their applications in non-ideal, real-life environments.
DOI: 10.5286/isis.e.rb1510225
title: Speciation and complex-ion formation in protic ionic liquids

description: A broad fundamental understanding of the design and properties of ionic liquids underpins their developing and future applications, which include accessing cellulosic polymers and renewable chemicals from biomass, production of cleaner fuels, remediating environmental pollution from toxic heavy metals, as well as new materials for cleaner, efficient batteries and fuel cells. This proposed study aims to explore the complex structures formed at the atomic level within ionic liquid systems of interest for use in fuel cells, and to help better our understanding of the mechanisms that can be used to control their fundamental properties.
DOI: 10.5286/isis.e.rb1510288
title: Magnetic excitation spectra in the field induced quantum phases of the quasi-1D Ising-like antiferromagnet SrCo2V2O8

description: We propose to investigate the magnetic excitation spectra in the three accessible magnetic ordered phases of the quasi-1D S-1/2 Ising-like antiferromagnet SrCo2V2O8 by single crystal inelastic neutron scattering using the LET. The magnetic phase diagram [for H // (001)] exhibits a series of field-induced quantum phase transitions as a function of field and temperature (below  ~ 1.5 K), from AFM ground state to incommensurate longitudinal spin density wave state (AFM-II) at 3.7 T, and then to a second ordered quantum state (AFM-III) at ~ 7 T.  We wish to investigate the development of the spinon continuum and bound states and to investigate how they are transformed in the two field-induced longitudinal spin density wave phases. Outcomes of the proposed investigations are expected to give experimental verification of the theoretical predictions.
DOI: 10.5286/isis.e.rb1510412
title: Hydrogenation of Benzene followed by Total Scattering and in situ 13C NMR

description: Catalysis is defined as the increase of the rate of the reaction or directing the reaction to one of the thermodynamically permitted pathways that lead to different products. It has been estimated that over 80% of chemical processes in the industry use this chemical phenomenon at least at one step of the production process. Due to the importance of catalysis a large number of studies of its principles have been undertaken, but still little is known about the kinetics of liquid phase heterogeneous catalytic reactions. The aim of our research is to develop a tool that will ensure a full description of in situ reaction,i.e. the reaction mechanisms and mass transport of the reagents within the catalyst pores. This will be achieved by combining time-resolved neutron diffraction and 13C-NMR, which will monitor structural and compositional changes during the course of the reaction, respectively
DOI: 10.5286/isis.e.rb1510456
title: GiSANS measurement probing the separation of colloidal structures from the interface

description: Controlling self-assembly of colloidal particles to create ordered structures over large areas has attracted considerable attention due to the low cost and wide variety of applications. Latex particles can form well ordered 2D crystalline arrays at a solid-liquid interface over areas of about 20cm2. Quartz crystal microbalance data suggests that the particles are separated from a silica interface by a layer of water. In this study, the separation of colloidal structures from the interface will be probed and modified by changing the concentration of the salt in the dispersion. GiSANS measurement will be used to investigate the near surface structures of the particles, in particular exploiting  high resolution of the incident wave vector near the critical momentum transfer for total reflection. This permits probing different depths and hence the particle separation from the interface.
DOI: 10.5286/isis.e.rb1510477
title: Quantum renormalisation of spin waves in a square lattice antiferromagnet

description: The two dimensional Heisenberg antiferromagnet on a square lattice is one of the most studied model in quantum magnetism . This is in part due to its intrinsic interest but also to the fact that both the cuprates and the pnictides superconductors belong to this class of model. In the fully quantum case with S=1/2,an outstanding theoretical and experimental challenge is to understand how the excitations evolve as a function of applied magnetic field. Specifically, we wish to investigate how the spinon continuum evolves into a novel mode for finite magnetic fields and to compare our experimental results with state-of-the-art theoretical models.
DOI: 10.5286/isis.e.rb1520196
title: Probing bulk heterojunction (BHJ) thin films with graded morphologies using SANS

description: This projects aims to contribute to a better understanding of the relationship between processing conditions, active layer morphology and device performance in polymer solar cells (PSCs). To this end a series of SANS experiments are envisaged, to provide the most detailed understanding possible of the processing-morphology-performance relationships in polymer:fullerene solar cells based on those polymers with the best power conversion efficiencies (PCEs), namely PCDTBT, PTB7 and PBDTTT-EFT. Optimized organic photovoltaic (OPV) processing, with its associated low production costs, would radically change the renewable energy paradigm that is key for opening solar energy to new markets such as those in developing countries where people wouldn?t normally think about investing in and generating their own electricity.
DOI: 10.5286/isis.e.rb1610202
title: Investigation of the Evolution of Broken Time Reversal Symmetry in Pr1-xNdxOs4Sb12

description: PrOs4Sb12 is a 1.85 K superconductor.  Its superconductivity shows unconventional behavior, and the originating mechanism remains unknown.  One characteristic is an internal magnetic field detected in the superconducting state of PrOs4Sb12, which breaks the time-reversal symmetry and does not appear in conventional type superconductivity.  The isostructure compound NdOs4Sb12 becomes ferromagnetically ordered below 0.9 K.  We have been investigating the effect of ferromagnetic moment of Nd on the unconventional superconductivity of PrOs4Sb12.  This proposal plans to use the zero-field muon-spin-relaxation measurements to monitor the evolution of broken time reversal symmetry in the series of Pr1-xNdxOs4Sb12.
DOI: 10.5286/isis.e.rb1610508
title: A Study of AuMu^+ Final States by Dia RF Resonance

description: Small-sized metal nanoparticles (NPs) are of long standing interest to both magnetism and heterogeneous catalysis. Muon studies of Au NPs encapsulated in 'SBA-15' silica are underway at TRIUMF with the aim of understanding the interaction of Mu(H) with the Au NP system. Evidence from these measurements suggests the formation of an AuMu^+ final state as the Mu atom loses its electron the metal surface. Results suggest faster chemical addition for smaller nanoparticles, consistent with an anticipated enhanced catalytic effect. The Radio Frequency measurements proposed here provide a sensitive method both to confirm the final state species and to directly measure its formation rate. The study should also reveal the magnetic nature of the surface from the RF line widths.
DOI: 10.5286/isis.e.rb1620039
title: Neutron diffuse scattering from multiferroic single crystal BiFeO3

description: BiFeO3 is a canonical multiferroic material.  We know that local (nanoscale) order is crucial in explaining the behaviour of conventional ferroelectrics, and reciprocal space mapping to measure diffuse scattering from a single crystal is the best way of exploring local order. Yet no one has ever mapped the diffuse scattering from BFO, despite the vast number of studies undertaken.  By studying the crystal structure of bismuth ferrite in unprecedented detail using SXD, we will better understand how its technologically useful properties arise and how to improve them.  Neutrons are ideal because BFO is a magnetically ordered system and the behaviour of the oxygen atoms is crucial.
DOI: 10.5286/isis.e.rb1620124
title: Slow spin dynamics and magnetic correlations in a pyrochlore magnet

description: The rare earth titanates and stannates cristallising in the pyrochlore crystal structure are prone to magnetic frustration effects due to the topology of their lattice. We have recently shown that the Nd2Sn2O7 pyrochlore orders in a so-called all-in--all-out magnetic structure, and that its dynamics is anomalously slow in the paramagnetic phase. We associate this feature with short range correlations that have been evidenced in several pyrochlore systems especially from neutron scattering experiments. We have partly characterized the slow dynamics of Nd2Sn2O7 in preliminary muSR measurements. In particular, the temperature dependence of the fluctuation rate suggests that clusters of spins rather than individual spins are at the origin of the slow dynamics. To ascertain this interpretation, we need to complete our experimental data.
DOI: 10.5286/isis.e.rb1620132
title: Engineering exchange strength in S=1/2 molecule-based magnets

description: Recent progress in the field of molecular magnetism has shown the potential for gaining control over the structural building blocks of molecular materials in order to engineer desirable magnetic properties. This was particularly evident in our recent work, where we showed that with small structural changes we could tune a system from a one-dimensional magnetic chain to an effectively zero-dimensional system which showed quantum spin-dimer behaviour. Our research has proved important in demonstrating how structure promotes and controls certain exchange pathways. Here we wish to investigate, in detail, how particular molecular ligands - pyrazine and 4,4' bipyridine - can be used to promote strong and weak exchange coupling. Specifically, we wish to study Cu(NO3)2(pyz)3 and [Cu(4,4-bipy)(H2O)2(BF4)2].4,4-bipy, which exploit new and different routes to realizing highly ideal model systems.
DOI: 10.5286/isis.e.rb1620310
title: Motion of Positively Charged Muonium Centres in Rutile and Anatase Titanium Dioxide

description: We propose a detailed study of the motional dynamics of Mu and the low temperature Mu0-like states in anatase and rutile Titanium Dioxide (TiO2). An initial study on only rutile TiO2 has been completed where low TF measurements have found a Mu0-like state where the muon is coupled to an electron localized on a nearby neighbouring Ti3+ ion where two inequivalent Mu bonding configurations are measured. Significant differences in the rutile versus anatase structure open questions about the local environment in each distinct phase. A complete characterization of motional dynamics associated with this state is essential for progress in understanding the true Mu properties and behaviour. This study will provide essential data relating to the H impurity for any technological application and supplement the ongoing study of Mu excitonic states and behaviour via IR Illumination in rutile TiO2.
DOI: 10.5286/isis.e.rb1620322
title: An investigation on the effects of cationic disorder on the ground state spin-orbit doublet of CoV3O8

description: The proposal deals with understanding the paramagnetic fluctuations in CoV3O8 which have recently been investigated on MARI.  This material displays cation disorder and strong low energy magnetic fluctuations to temperatures over 10 x Tn.  Higher energy resolution data is required to complete this study and to fit an appropriate scaling curve to the data (several possible models are discussed in the proposal and lower energy data is required to complete this).  To complete this study we request 5 days on IRIS.
DOI: 10.5286/isis.e.rb1620351
title: Investigation of antiferromagnetic long-range interactions in Co-based Heusler alloys

description: Ni-Mn based Heusler alloys with composition related to the stoichiometry Ni2MnX, with X belonging to the IIIA-VA chemical species, are widely considered as a class of multifunctional magnetic materials. This magnetic phenomenology is related to the martensitic transformation undergoing from ferromagnetic cubic austenite. Depending upon the chemical composition, different martensitic structures are stabilized showing strong lattice distortions. Recently in Co-doped Ni-Mn-Ga ternary Heusler alloys have shown that during martensitic transformation it is observed a drastic drop of the magnetization. Preliminary neutron diffraction experiments on Co-based Ni-Mn-Ga alloy provided clear evidence of a long-range antiferromagnetic ordering in the tetragonal martensite. We suggest to extend the structural study of AF long-range state to others Co-doped Ni-Mn-Ga and Ni-Mn-Sn compositions.
DOI: 10.5286/isis.e.rb1620460
title: Time dependent magnetic structure of Sr3NiIrO6

description: We have reported magnetic structure of Sr3NiIrO6, which gives two possible solutions.  Our theory shows that reported magnetic structure is not ground state magnetic structure. We would like to investigate time dependent magnetic structure of Sr3NiIrO6 to test our theory.
DOI: 10.5286/isis.e.rb1670541
title: Exploratory study of the delocalization of a TCNQ radical under pressure
DOI: 10.5286/isis.e.rb1670557
title: Effect of light irradiation on charge carrier dynamics in active layer hybrid solar cells
DOI: 10.5286/isis.e.rb1710095
title: High Field muon spin rotation studies in Ni-Mn-(Sn,In) based metamagnetic shape memory alloys

description: We have recently performed zero field muon spin rotation (muSR) studies of one the shape memory alloy  Ni2.04Mn1.4Sn0.56 on EMU spectrometer at ISIS and the observed results are quite interesting. The multiple magnetic transitions are beautifully depicted in the muSR data. Most importantly, it clears some of the doubts regarding the thermal variation of different magnetic phases. The alloy is characterized by strong magnetic field induced magneto-structural transition which is the key to its functional properties. It is essential that one should study the similar muSR in presence of suitable longitudinal magnetic field.  Considering rich phase diagram with respect to magnetic field and temperature, we propose to perform muSR study under 50 kOe of magnetic field on the same alloy along with two more related compositions in HIFI spectrometer in the temperature window 10-350 K.
DOI: 10.5286/isis.e.rb1710220
title: Examining the magnon-magnon/phonon coupling in a new multiferroictwo-dimensional triangular lattice antiferromagnet LuFeO3

description: Non-collinear two-dimensional triangular antiferromagnets (2D TLAF) are currently an area of much active research due to their unique magnetic properties which lead to non-trivial quantum effects that experimentally manifest themselves in the spin excitation spectra. Our research group has previously done experiments to definitively demonstrate such magnon-magnon and magnon-phonon coupling effects in the multiferroic LuMnO3. Now that a large enough single crystal of the recently discovered multiferroic material LuFeO3 is available, we propose to obtain its spin wave spectra via neutron scattering as well. Comparing the data for isostructural LuFeO3 and LuMnO3 will allow us to achieve a better understanding of how sensitive the magnon-magnon and magnon-phonon coupling properties are to the specific details of the sample parameters.
DOI: 10.5286/isis.e.rb1710303
title: Spin anisotropy in the isovalent doped iron pnictides Ba0.9Sr0.1Fe2As2

description: Understanding the electronic anisotropic state at a temperature associated with the nematic phase is unresolved problems in iron pnictides. Although many experiments focus on electron nematic phase, the origin of such nematic phase is still debated. Theoretical proposals explored two scenarios for nematic order, spin or orbital. No matter which one is the driving force, that could induce the strucural transition and magnetic transition. Considered that the structural transition is a second order in BaFe2As2 but a first order in SrFe2As2. Our recent time-of-flight neutron scattering experiments on detwinned BaFe2As2 and SrFe2As2 have been successful carried out, and reveal that the spin nematiciy of SrFe2As2 ceases at Ts, but for BaFe2As2 ceased above Ts. It will be interesting to explore the spin nematicity in Ba0.9Sr0.1Fe2As2,which on the critical point of first order and second order.
DOI: 10.5286/isis.e.rb1710319
title: A biophysical approach of studying the molecular interactions of a novel antibiotic with the Gram negative bacterial cell envelope.

description: Gram negative (-ve) bacteria possess numerous defenses against antibiotics, not the least of them being the intrinsic permeability barrier afforded by their outer membrane (OM) and various efflux mechanisms which pump out drugs. A novel compound was synthesized at the KCL which shows promising activity against Gram (-ves). However, there was a noticeable effect of drug efflux resulting in reduced efficacy. This project investigates novel formulations to increase OM permeability to the antibiotic. Drug/enhancer complexes were made, which pass into the cell and dissociate thereby circumventing intrinsic resistance and membrane-associated efflux mechanisms. Neutron reflectivity will offer a greater insight into the intimate molecular drug (pure and formulated)-membrane interactions in order to understand how drug uptake may be improved for achieving optimal antimicrobial activity
DOI: 10.5286/isis.e.rb1710416
title: Neutron diffraction analysis of alpha- and beta-polymorphs of nanoscale metal hydroxides: the role of intercalated water molecules

description: The hydroxides Me(OH)2 of the bivalent transition metals Co, Cu, Fe, Mn, Ni, Cd and Zn play critical roles as sorbents, catalysts or reductants in many environmental and electrochemical applications. These hydroxides can form in different forms depending on the composition of their interlayer space. The compact b-form contains no intercalated guest species whereas the a-form can host water molecules and anionic species leading to an expanded basal dimension of the unit cell. Well-crystalline b-Me(OH)2 are commonly synthesised at high temperatures rendering the a-forms undiscovered or poorly characterised. This study builds on a recent discovery of a-Fe(OH)2 material studied at GEM and aims to provide complete crystallographic details and relationships between a- and b-Me(OH)2 forms, and a better understanding the dynamics and role of intercalated water in structural stability.
DOI: 10.5286/isis.e.rb1761002
title: Copy of: Characterization of Indo-Persian blades of the Wallace Collection

description: This experiment is a continuation of a previous one aiming to analyse the composition and microstructure of Indo-Persian swords and daggers of the Wallace Collection whose aspect indicates they are made of wootz steel (also known as Damascus steel) which was prduced by very slowly cooling and very carefully forging the metal so as to preserve a surface pattern which was highly esteemed as a visible indicator of the blades metallurgy. Unfortunately many Victorian collectors and dealers (from whom Sir Richard Wallace purchased much of his arms and armour collection) over-polished them because they did not appreciate the reasons for their dark silver-grey appearance. We propose to measure a second set of 16 selected Indo-Persian blades from the Wallace Collection in order to broaden our understanding of their different compositions and micro-structures, and hence their manufacture.