Ammonia-water mixtures are abundant throughout the universe, playing a key role in planetary and astrophysical processes. When rapidly cooled, these mixtures do not readily crystallise, instead they form an amorphous phase of ammonia dihydrate (ADH). Neutron data was collected at ISIS on both ambient and pressurised low temperature ADH, revealing important distinctions between the liquid and two distinct amorphous structures - one at ambient pressure and another at pressures above 1.5 GPa. I will explain how Empirical Potential Structure Refinement (EPSR) is used to determine structural information from disordered materials and show key results from AIASSE about how the topology of amorphous ADH changes with pressure. //// Thermal diffuse scattering (TDS) has seen some level of revival over the past 25 years as a technique for studying the lattice dynamics of crystals. One of the key advantages of TDS is its rapid data collection when compared to experimental techniques such as inelastic neutron scattering. We are developing methods for the novel approach of collecting and analysing TDS data from single crystals under high pressure, taking advantage of the fast data collection to determine full sets of phonon dispersion relations for a material over a range of pressures. I will explain how this technique works, and how we are using it to investigate phonon anharmonicity in various metal halides including NaBr, AgCl and CsI.