Oxides under Extreme Conditions: Pushing the Limits of Neutron Diffraction

The LaCoxMn1-xO3 perovskite series has been widley studied as responses to chemical composition or volume give rise to a variety of electrical and magnetic properties [1]. Volume changes can be induced by the application of pressure, which can be used to study structural-property relationships. High-pressure neutron-diffraction experiments have been performed on LaCo0.9Mn0.1O3 and LaCoO3 powders. Neutron powder diffraction is essential to determine the structure of perovskite-like oxides. The high-pressure structural evolution of LaCo0.9Mn0.1O3 will be presented [2]. The change in tilting angle and strain has been determined upon pressure. This study compliments high-pressure magnetisation measurements, where the Curie temperature shows a strong dependence on applied pressure. A structural study of LaCoO3 as a function of pressure and temperature using neutron diffraction will also be presented [3]. This study is of great interest for its unique temperature-dependent electronic properties. Tha aformentioned experiments have been carried out on the PEARL instrument, the highpressure-dedicated diffractometer at ISIS, STFC [4]. We are developing new pressure cells for neutron diffraction to extend the maximum achievable pressure at ISIS.