cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1820592
title: INS investigation of post-pressurised Cs2CuCl4

description: Cs2CuCl4 has been extensively studied using neutron scattering, and has revealed a quantum spin liquid phase below 2.8 K with antiferromagnetic interactions, and long range magnetic order below 0.62 K. Intriguingly, it has now been shown that when single crystals are subjected to 5kbar of hydrostatic pressure for 2 days, upon releasing the pressure, long range magnetic order is instead observed up to 9 K, yet X-ray diffraction has revealed no clear structural changes. Potentially post-pressurised Cs2CuCl4 is less frustrated with a more quasi-one-dimensional antiferromagnetic spin 1/2 ordered magnetic state, and therefore we aim to investigate the effects of post pressurisation on the excitation spectrum to gain an insight into how the magnetic interactions have been modified.
DOI: 10.5286/isis.e.rb1900132
title: μSR study on Heisenberg spin ½ dimer NH4CuPO4·H2O

description: Heisenberg spin 1/2 systems show exotic nature of ground state, which gives rise to a number of interesting quantum phenomena, like being a state of quantum mechanically entangled spins which also exhibits its signature at finite temperature. Such entangled spin qubits can be exploited to test protocols of quantum computation. Studies have shown intimate connection between magnetism and quantum correlations like entanglement, discord etc. Hence to implement protocols of quantum information more efficiently, a clear picture about magnetic ordering and magnetic interactions among the spins are necessary. Therefore, the motivation of the project would be to investigate the unexplored magnetism in the system by muSR which is hard to capture by thermodynamic measurements, and to use that knowledge from muSR in developing quantum computation protocols aimed to be implemented on the system.
DOI: 10.5286/isis.e.rb1900133
title: The Effect of Temperature on Liquid 1-Methylnaphthalene Structure: An Integrated Diffraction and Simulation Approach

description: We are studying asphaltene behavior in multiple solvent environments to investigate the key motives behind polyaromatic hydrocarbon self-aggregation. We have found that 1- methylnaphthalene (1-MN) molecules tend to stack more with parallel alignment when the temperature is increased, despite a more disordered system being expected following a conventional interpretation of entropy.  We are presuming that unconventional forces (e.g., forces induced due to shape entropy) are responsible for this behavior. The behavior of increased order with temperature is well-known in hard particle and colloidal systems, but for liquid aromatic solvents, this phenomenon is still unreported. We aim to perform neutron scattering experiments at repeated and additional temperatures to observe if this novel trend in the fluid aromatic system is real and our preliminary investigations are valid.
DOI: 10.5286/isis.e.rb1910025
title: Possible high-temperature polar phases in the [110] layered perovskites NdBaInO4 and YBaScO4

description: Geometric ferroelectrics are an unusual and rare class of materials which exhibit spontaneous electrical polarisation due purely to 'geometric' effects, i.e. caused by atomic size mismatch, rather than 'electronically' driven factors. The compound LaTaO4 is one case, which is particularly unusual in showing a transition to such a state on INCREASING, rather than decreasing temperature. In this proposal we seek to characterise two new compounds, distinct from, but closely related to LaTaO4, which we believe may show a similar 'geometry-induced' electrical polarisation. The apparent phase transition of one of these, has previously been overlooked in the literature. We will use high-resolution powder neutron diffraction to ascertain whether these new materials do indeed display this unusual behaviour.
DOI: 10.5286/isis.e.rb1910030
title: An S = 1/2 chiral staggered chain in a magnetic field

description: The molecule-based chiral spin chain, [Cu(pyrimidine)(H2O)4]SiF6·H2O exhibits staggered g-tensors, a rich low-temperature excitation spectrum and a spin gap that opens on application of magnetic field. These phenomena are reminiscent of those previously observed in non-chiral staggered chains, which are explicable within the sine-Gordon (SG) quantum-field theory. In our case, however, the size of the gap and its measured linear field dependence do not fit with the SG model as it stands. We have proposed that the differences arise due to additional terms in the Hamiltonian resulting from the chiral structure, particularly a uniform Dzyaloshinskii-Moriya coupling and a four-fold periodic staggered field. These proposals can be confirmed via determination of the static magnetic structure of the gapped ground state that exists at low temperatures under small applied magnetic fields.
DOI: 10.5286/isis.e.rb1910214
title: SANS Studies of Nanostructures of Microfluidically Fabricated lipid Nanoparticles for Plasmid DNA Delivery

description: We have developed a new approach for forming lipid nanoparticles (LNP) with and without interfering RNA and DNA  from a microfluidic setup. The LNPs are formed by an ionisable cationic lipid, helper lipid, cholesterol and a poly(ethylene glycol) (PEG) lipid, and the different components can self-assemble with the payload via the microfluidic mixing system. These RNA or DNA loaded LNPs mimic those reported in the literature as promising delivery vectors and work by collaborators in MedImmune has demonstrated their high transfection efficacy and low toxicity for different cell lines. Following our DLS and related characterisations, we seek to exploit the unique feature of SANS coupled with contrast variation to determine the inner structures of LNPs, thus relating the plasmid DNA transfection to the LNP inner structures tuned by different help lipids.
DOI: 10.5286/isis.e.rb1910248
title: Effect of Cholesterol on NHE1 intracellular domain adsorption on lipid bilayers

description: The Na+/H+ exchanger isoform 1 (NHE1) is a transmembrane protein with the primary function of regulating the pH in the cytosol by exchanging one proton with one Na+ ion. The NHE1  intracellular domain (ICD) is an intersically disordered proteins which regulates protein activity via binding of other proteins, as well as by interacting with the anionic phospholipids in the membrane. Although a specific lipid interaction domain (LID) in NHE1/ICD (named here after NHE1/LID) was identified, a detailed picture of the mechanism of NHE1-lipid interaction is still missing. The investigation of NHE1/LID interaction with lipid membranes is part of a larger project, which aims at the characterization of ICD-lipid membrane co-structures. Here we propose to perform Neutron Reflectometry (NR) experiments to investigate how cholesterol can affect NHE1/LID adsroption on lipid membranes.
DOI: 10.5517/ccdc.csd.cc21lmv4
title: CCDC 1894746: Experimental Crystal Structure Determination

description: Related Article: Chao Xu, Ming-Ming Sheng, Hua-Tian Shi, Maria Strømme, Qian-Feng Zhang|2019|Dalton Trans.|48|5505|doi:10.1039/C9DT00480G
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: 10.5517/ccdc.csd.cc21lmx6
title: CCDC 1894748: Experimental Crystal Structure Determination

description: Related Article: Chao Xu, Ming-Ming Sheng, Hua-Tian Shi, Maria Strømme, Qian-Feng Zhang|2019|Dalton Trans.|48|5505|doi:10.1039/C9DT00480G
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: 10.5517/ccdc.csd.cc22174j
title: CCDC 1907806: Experimental Crystal Structure Determination

description: Related Article: Andrey Ilyukhin, Irina Krilova|2019|CSD Communication|||
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.rb1520000
title: Ruddlesden Popper Ca2MnO4 - a Material Exhibiting a New Type of Negative Thermal Expansion Mechanism?

description: The Ruddlesden-Popper (RP) compounds An+1BnO3n+1 exhibit a broad range of technologically interesting properties such as high-Tc superconductivity, colossal magnetoresistance, metal to insulator transitions and ferroelectric / multiferroic ground states. In a study of one of these compounds Ca3Mn2O7, we have recently made the remarkable discovery of significant negative thermal expansion. This has led us to propose a new mechanism and strategy for designing NTE materials.  We request now two days on HRPD to study the closely related phase Ca2MnO4 which prior indication suggest also exhibits substantial NTE.  This work will provide the community with a better understanding of this new NTE mechanism enabling the future design of new materials with enhanced properties.
DOI: 10.5286/isis.e.rb1520045
title: Studying weakly hydrophobic guest hydrates and  ammonia-water gas ternaries by INS on TOSCA

description: The proposing team has a well established experience in the use of INS on samples containing molecular hydrogen. Our recent experimental results on various types of H2 clathrate hydrates, obtained on TOSCA, allowed investigating the quantum dynamics of the guest H2 molecules inside the host cage, as well as the phonon density of states of these ice-like lattices. Now this new proposal aims to study both the host and the lattice dynamics of clathrate hydrates of different structure and composition: (1) weakly hydrophobic guest hydrates containing H2S; (2) water-ammonia ternaries with tetrahydrofuran and hydrogen. From the TOSCA spectra it will be possible in former case to derive the rattling and the rotational dynamics of the H2S molecules inside the cages, while in the latter case to probe the pronounced effects of the strong H-bonds associated to the NH3 molecules in the host lattice.
DOI: 10.5286/isis.e.rb1520176
title: Confined water in a geo-polymer system

description: The main objective of this proposal is to investigate the dynamics of ultra-confined water in the slits pores of geological cavities (mineral tobermorite). This system provides an excellent model to analyze the dynamical properties of water confined in cement-like materials, which are much more complex than tobermorite due to their different pore sizes. Furthermore, the severe confinement of tobermorite will prevent crystallization of the water at any temperature and make it possible for us to combine the present QENS study with broadband dielectric spectroscopy (BDS), covering the frequency range 10-2 - 109 Hz and therefore also a broad temperature range. The main aim of this study is to compare the water dynamics in natural and synthetic tobermorite and to determine the physical nature of the relaxation processes observed by BDS.
DOI: 10.5286/isis.e.rb1520203
title: Measuring the strain profile in opposed sapphire anvils

description: Sapphire can be used as a hard anvil material to generate high pressures on other samples of interest. Sapphire anvils, though not as strong as diamond anvils, are easily obtained in much larger dimensions than diamond, and able to hold larger sample volumes. Finite element simulations (FEA) have been performed to try to optimise and extend the pressure range of the weaker sapphire anvils. Recent results suggest that the compressibility of sapphire results in a large build in tensile strain behind the flat contact surface between the anvil and the sample. As is true for all FEA simulations the results need to be verified against experimental data, and neutron scattering offers a unique tool for comparing strains like for like in the bulk of the anvil. This study proposes a 3 day experiment on Engin-X to measure the strain profile in a single crystal sapphire anvil under load.
DOI: 10.5286/isis.e.rb1520240
title: Thermal fluctuations of cold shock proteins from different flavours of extremophilic organisms

description: Extremophiles are organisms which survive and thrive in extreme environments. The proteins from extremophilic organisms have received considerable attention as they are structurally stable and functionally active under extreme physical and chemical conditions. Our goal is to obtain the design principles which accurately describe the interactions which allow extremophilic proteins to be stable and flexible at extreme temperatures. We wish to combine neutron scattering experiments with a range of other experimental and computational tools to provide a complete picture of the protein's structure and dynamics. This will provide fundamental insights into the mechanisms of adaptation of extremophile organisms, in addition to providing a foundation for the development of an understanding of biological molecules that can be exploited in synthetic biology, industry and bionanotechnology.
DOI: 10.5286/isis.e.rb1520311
title: Cation Ordering in Quaternary Sulphides and Selenides

description: We wish to investigate quaternary chalcogenides, A2ZnBQ4 (where A = Cu, Ag; B = Ge, Sn; Q = S, Se). Calculations indicate stannite (S) or kesterite (K) superstructures of both zinc blende (ZB) and wurtzite (W) type structures may result from cation ordering. Powder X-ray diffraction data at room temperature have generally been indexed on the basis of the tetragonal S-type structure but the presence of cations with similar X-ray scattering powers prevents determination of cation ordering schemes. The similarity of diffraction patterns for S and K derivatives introduces further ambiguity; phases such as Cu2ZnSnQ4 being described in several superstructures. The structure adopted also appears to be dependent on temperature. We will exploit the contrast afforded by neutrons to establish unambiguously the cation distribution at room temperature and investigate its evolution with temperature.
DOI: 10.5286/isis.e.rb1520378
title: Dy3Mg2Sb3O14 - a 2D Kagome lattice with Classical Ising Spins

description: Dy3Mg2Sb3O14 forms a layered structure with magnetic Dy3+ ions forming sheets of corner sharing triangles, called a Kagome lattice. The Ising magnetic moments are constrained to point either in or out of the triangles  and a rich magnetic phase diagram is predicted from Monte Carlo simulations. This experiment will explore the structural and magnetic properties of Dy3Mg2Sb3O14 as a function of temperature, it aims to a) understand how the structure of Dy3Mg2Sb3O14, in particular the oxygen ion positions impact the magnetic properties and b) explore the low temperature magnetic structures which form when Dy3Mg2Sb3O14 is cooled. The predicted magnetic states include two with short but no long range magnetic order, these will be studied using magnetic PDF and reverse Monte Carlo simulations.
DOI: 10.5286/isis.e.rb1520487
title: Neutron Total Scattering Investigation of Temperature Driven Transitions in LaCoO3

description: This proposal is concerned with determining the local structure of LaCoO3 and observing changes within this as the material undergoes some well characterised temperature driven electronic transitions. At low temperature (&lt; 50 K) LaCoO3 is a non-magnetic insulator with the trivalent cobalt in the low spin state configuration t2g6eg0. At ~100 K the material becomes paramagnetic and with increasing temperature the high-spin t2g4eg2 configuration is populated. Above 648 K charge transfer between spin states occurs and disproportionation into Co2+ and Co4+ species is observed.
DOI: 10.5286/isis.e.rb1820062
title: Nature of Disorder in Relaxor-like Ferroelectric AB(HCO2)3 Frameworks

description: Relaxor ferroelectics are of significant interest for use as piezoelectric actuators in sensing applications and for high precision mechanical stages. Relaxors are traditionally associated with disorder induced by a complex mixture of cations in complex oxides. Recently framework materials built from inorganic and organic building blocks have been shown to exhibit relaxor-like properties without the requirement for such complex doping, a unique avenue to such behaviour. We propose to study two of these relaxor-like ferroelectrics, NH4Mn(HCO2)3 and NH4Zn(HCO2)3, using quasielastic neutron scattering to establish the dynamics of the disorder responsible for their physical properties and how this varies with the different relaxor properties of these materials and between their polar and non-polar phases. This will be complimented by NMR and diffraction measurements currently underway.
DOI: 10.5286/isis.e.rb1820222
title: Study of cold creep stress relaxation on stainless steel welded structures

description: ATLAS+  is a four year, 7M Horizon 2020 project aimed at developing and validating advanced structural integrity assessment methodologies for non-RPV primary circuit pressure boundary components. Two thin-walled welded pipe mock-ups are being manufactured as part of ATLAS+. The proposed experiments on the welded mock-ups have three objectives. First, they serve as an important step in the validation of potentially challenging weld residual stress simulations for thin walled pipes. Second, the measurements are required to fill in gaps in the current population of pipe girth weld mock-ups required to train Artificial Neural Networks for prediction of residual stresses. Third, the measurements are aimed at studying, for the first time, the relaxation of residual stresses during cold creep in stainless steel welded structures simulating the in-service conditions of future nuclear reactors.
DOI: 10.5286/isis.e.rb1820630
title: In situ phase volume fraction and internal strain measurements of TRIP steel under tension subjected to temperature change

description: Transformation Induced-Plasticity (TRIP) phenomenon has been intensively studied to developnew steel products with the optimal combination of formability and strength. However, themechanical behaviors of TRIP steel and the deformation mechanisms of phase transformation arenot clearly understood. Furthermore, the TRIP phenomenon is sensitive to temperature and thestability of the retained austenitic phase inherited from manufacturing processes. Therefore, weare planning to investigate the mechanical behavior, evolution of phase volume fraction, andevolution of internal elastic strain of TRIP steel under tension at room temperature, -100°C and at-200°C using ENGIN_X at ISIS. The experimental results will be valuable to improve and validatethe elasto-viscoplastic polycrystal model addressing phase transformations.
DOI: 10.5286/isis.e.rb1900129
title: Induction furnace for POLARIS; second in-beam test

description: The induction furnace build for POLARIS was tested in-beam for the first time in November 2018.Since then adjustments has been made to the copper coils which has been coated with boronnitride (BN) in order to minimise scattering from the setup whilst keeping a large beamsize. Alsochanges has been made to the sample holder which now consists of a steel tube instead of aquartz tube. This has decreased the thermal gradient within the sample drastically. During thesecond in-beam test we wish to investigate the new scattering profile using the BN coated coppercoils and replicate an experiment performed at GEM in May 2018 during which the magneticmoment of CoFe2O4 is followed during elevated temperatures.
DOI: 10.5286/isis.e.rb1910127
title: Field effect of the magnetic ground state in a triangular-lattice magnet

description: Rare-earth frustrated magnets have attracted great interest because they can form rather complex ground states such as hidden order phases, the order parameters of which cannot be disclosed by conventional magnetic probes including the neutron diffraction experiments. Our recent LET experiments on a triangular-lattice magnet TmMgGaO4 revealed an exotic intertwined multipolar and dipolar order under zero magnetic field. The dipolar order is caught by the neutron diffraction and the quantum fluctuation of the multipolar moments leads to the sharp spin wave. Moreover, it has been proposed that the magnetic field will tune the multipolar order and its quantum excitations will be modified. Here we propose to study the spin excitations of TmMgGaO4 under various magnetic fields so that the field dependent evolution of the hidden order and its quantum excitations can be decided.
DOI: 10.5286/isis.e.rb1910326
title: Probing Transition Metal Migration in Cathode Materials for Na-ion Batteries with Neutron PDF

description: Sodium layered oxides as cathode for Na-ion battery could exceed the energy density offered by Li-ion cathode thanks to two main advantages: (i) the activation of Fe3+/Fe4+ in Na2/3Fe1/2Mn1/2O2 and (ii) Oxygen redox without Oxygen loss in Na2/3Mn2/3Mg1/3O2. However those materials suffer from capacity/voltage fade or huge voltage hysteresis that limit their practical interest. We managed to combine those advantages while preventing their drawbacks in Na2/3(Mg,Mn,Fe)O2. The origin of such improvements is probably nested in the transition metal migration during (dis)charge. As neutron source offers a very good contrast between Fe/Mn/Mg and Na (contrarily to X-rays) and PDF is able to solve the short/medium range structure of those defected materials, neutron PDF appears to the only technique able to unambiguously reveal the transition metal migration during cycling.
DOI: 10.5286/isis.e.rb1910341
title: Modulation in Molecular Materials under Pressure

description: Modulation has been understood and used to explain physical properties in solid-state materials for many years. Molecular modulated structures relatively scarce, but due to technological advances can no longer be ignored. Systematic variable temperature studies of the derivatives of Barluenga's Reagent has shed some light on why some of these salts exhibit modulation. Application of pressure allows the exploration of more of the phase diagram allowing access to new states and expanding our knowledge. A better understanding of the causes of modulation in simple molecular systems will aid our treatment of the pathological cases where solution currently eludes us.
DOI: 10.5286/isis.e.rb1910464
title: Mapping of micro-strain and macro-strain evolution by shot, laser-shock, and cavitation shotless peening using neutron transmission

description: Peening is a surface treatment method to improve the fatigue life of engineering components. Recent development of peening technique such as laser-shock and cavitation shotless peening were introduced as an alternative to conventional shot peening. Previous study has shown that cavitation shotless peening (CSP) was not only introduce macro-strain onto the surface of components but also simultaneously relieve micro-strain of quenched metallic materials. In order to get a better understanding on the mechanism and the extent of the effect of CSP on macro- and especially micro-strain, as compared to shot and laser-shock peening, we propose Bragg-edge transmission imaging study at IMAT. Through Bragg-edge analysis, 2D map of macro- and micro-strain and it's evolution due to different types of peening and different peening parameters can be observed.