Mark Warren is a Postdoctoral Research Associate on the small-molecule single-crystal diffraction beamline, I19.  His main research interests are in studying the solid state structural changes of materials by changing their sample environment, and using crystallography to monitor these changes. This includes the use of diamond anvil cells to study material changes under high pressure, the environmental gas cell to monitor gas adsorption and desorption in framework materials, illumination methods to study photo-induced processes and variable temperature experiments on materials.