Experiments performed in our laboratory indicate that maleic acid undergoes an unexpected structural change when subject to high pressure and temperature conditions. For these experiments, a high pressure sample chamber is used that does not allow us to monitor the sample during the experiment. Ideally, we would be able to monitor the sample during application of high pressure and temperature conditions to identify specific conditions at which structural changes occurThe aim of the proposed experiment is to address the question of what structural changes are occurring to maleic acid as we apply high pressure and temperature conditions. We will use neutron diffraction to monitor the sample as we change the sample environment and the data collected will allow us to identify the solid form that is present in the sample chamber at well-defined conditions of pressure and temperature