Wombat is a high intensity neutron diffractometer located in the OPAL Neutron Guide Hall. It is primarily used as a high-speed powder diffractometer, but the high-performance area detector means that measurements have also expanded into texture characterisation and single-crystal measurements. Wombat is particularly optimized for the study of materials in situ and in operando, measurements...
The scattering function, S(Q,ω), representing the interaction between the incident neutron and the pseudopotential, representing an ensemble of atoms, may be determined in a variety of ways: Via classical force-field approaches, through electronic structure calculations, through analytical approaches and through a combination of one or both of the first two approaches and applying molecular...
To combat climate change, many industries are trying to reduce their greenhouse gas emissions via clean fuels such as hydrogen. However, hydrogen gas is not energy dense, so finding efficient methods of storing hydrogen is critical. Nitrogen reduction to ammonia is a promising form of hydrogen storage because of ammonia’s increased relative energy density and pre-existing transport...
Sulfobetaines are zwitterionic surfactants with peculiar properties such as high foam stability, temperature resistance and salt tolerance (SiTu et al., 2017). Sulfobetaines are widely used in body care products and kitchen detergents. Despite their widespread use, micelle self-assembly and packing are not explored. In this work, we study hydroxyl sultaines to develop high-performance and...
Emu is the high-resolution neutron spectrometer installed at the OPAL reactor, ANSTO.
It is well suited to characterizing diffusion and tunneling processes, such as occurring in e.g. polymer chains, membranes, proteins, molecular crystals, with relaxation times from a few 10 ps to over 1 ns due to Emu's high energy transfer resolution (1 µeV FWHM) and accessible ±31 µeV energy transfer range....
Polymer brushes- densely packed polymer chains tethered by one end to an interface- are a useful tool to control the interfacial properties of a substrate. These properties can be fine-tuned by control of the chemistry of the constituent monomer, as well as the thickness and grafting density of the brush. One such example are brushes composed of poly(dimethyl siloxane) (PDMS). Owing to its...
Electrolytes form a critical component of many systems from biological processes to energy storage. The Debye Hückel Theory has been extensively used to describe simple aqueous electrolytes, yet many applications of electrolytes involve significantly more complex matrices containing salt mixtures, high concentrations, complex ions or other co-solutes. Hypersaline solutions is one area of...
NaSICON-type materials (ceramic lattices of joined MO6 and PO4 polyhedra with interstitial alkali metals) are of interest due to their ability to have anisotropic metallic semi-conductivity due to delocalization of electrons along the octahedral chains.(1) “Filled” alkali metal containing NaSICONs have been shown to have positive thermal expansion, whereas some “empty” NaSICONs have been shown...
Spin polarised density functional theory can predict the magnetic moment and arrangement of spins in a crystal structure from ab initio calculations. We will present DFT calculations on transition metal doped SnTe, predicting the size of the magnetic moment for Fe,Cr, V, Ti dopants.
Once the size and spatial distribution of the magnetic moments is known from DFT, it is straightforward to...
Fe4Si2Sn7O16 has a well-ordered complex composite layered structure that incorporates perfectly hexagonal kagomé lattices of high-spin Fe2+ (S = 2) cations. Below TN = 3.5 K it adopts a unique “striped” magnetic structure [1,2] that breaks hexagonal symmetry and leaves 1/3 of the spins geometrically frustrated in an apparent “partial spin-liquid” state down to at least 40 mK. Polarised neutron...
An experimental inelastic neutron scattering (INS) study on atacamite (Cu2Cl(OH)3) has been performed using Pelican to verify previous density-functional theory (DFT) calculations of its magnetic exchange interactions. INS reveals two dispersive spin wave modes along the H direction. Comparison with linear spin wave theory (LSWT) modelling indicates a frustrated zigzag-chain system along the...
The Pelican spectrometer has been in operation at the Australian Centre for Neutron Scattering (ACNS) for the past decade. This versatile instrument is designed for a wide range of measurements on powders, single crystals, and liquids, offering broad wavelength and resolution capabilities suitable for various scientific applications. Inelastic neutron scattering (INS) experiments often require...
The ability to select and manipulate the spin of neutrons as part of scattering experiments enables unique information to be obtained for a variety of samples, ranging from detailed studies of magnetic ordering to the separation of coherent and incoherent scattering which can be especially useful for samples containing a significant amount of hydrogen. This poster will provide an overview of...
Echidna has just installed an improved monochromator, providing both increased intensity for common wavelengths and convenient access to a new wavelength, 2.05Å at the standard 140° degree takeoff angle. The new monochromator is characterised in this poster, together with insights into Echidna usage and exploration of performance limits, including: how little sample is needed? What is the...
Fe3GaTe2 is a 2D vdW layered material with an intrinsic ferromagnetism identified by above-room temperature Curie temperature (Tc) and a robust large perpendicular magnetic anisotropy (PMA). Previous studies have shown that 2D vdW ferromagnets are promising candidates for many magnetoelectronic devices and next-generation spintronic applications. However, these 2D materials must be stable at...
Small-angle neutron scattering (SANS) and ultra-small-angle neutron scattering (USANS) are useful methods that have been employed in many fields to investigate the micro-porous structure of rocks, ceramics, metals, polymers and even foods. These techniques provide statistical information on the distribution and structure of pores in a given sample from < 1 nm to ca. 60 μm (depending on the...
In this study, we introduce a novel class of aqueous electrolytes based on microemulsions that demonstrate an impressive high voltage window (2.2–2.5 V) and outstanding performance in supercapacitors. The electrochemical behavior is strongly influenced by the electrode morphology, specific surface area, and electrolyte composition. The extended voltage window is linked to the formation of a...
Multiferroic and magnetoelectric materials have been extensively studied in the past two decades due to their interesting properties and potential versatile applications. Magnetoelectric coupling is the fundamental mechanism of multiferroic and magnetoelectric properties in these materials. However, understanding magnetoelectric coupling mechanisms in these materials is a challenging task....
The traditional, “text-book” view [1] for the martensitic transformation in In-x at%Tl alloys, for 15.5 ≤ x ≤ 30.5, has been via a double shear such as: (101)[1 ̅01]; (011)[01 ̅1], on the basis of optical -microscopy observations [2] and measurements of the (c11 – c12)/2 elastic constant [3]. However, this model was called into question following measurements of the low-, [0][ ̅0]...
Taipan is a high-flux thermal-neutron triple-axis spectrometer with a traditional single-detector design. Taipan has been the power horse for thermal neutron inelastic neutron scattering experiments in Australian Centre for Neutron Scattering (ACNS) at Australian Nuclear Science and Technology Organisation (ANSTO) for the last ten years,$^{[1]}$ generating numerous beautiful scientific...
This poster will highlight some recent upgrades to the Kowari slit system including full motorisation of the primary slits and upgrades to the secondary slits. Of focus though, will be the plan to integrate an Aramis image correlation camera on the instrument to work in conjunction with the SScans virtual instrument software as well as the ATOS-5 structured light scanner. These upgrades when...
