Friday, March 24, 2017 - 11:15am Chemistry Building, Room 400 Physical Seminar With the development of X-ray Free Electron Lasers (XFEL), new techniques for studying ultrafast chemical dynamics have been established. These experiments can provide dynamic and structural information with femtosecond temporal and angstrom spatial resolution. The electrocyclization of 1,3- cyclohexadiene is a model system for many photoinduced reactions such as production of vitamin D3 or photochromic optical switches. The previous studies of 1,3- cyclohexadiene ring opening and improvements made with the XFEL diffraction technique will be presented.