X-ray induced ring-opening of organosulfur molecule 2-Bromothiophene

Ring-openings of organic molecules are predecessors of formation of life-critical compounds [1]. Organosulfur molecules are known for their importance in natural life processes and artificial drug formation. Ring-opening dynamics has been investigated via direct UV- photo-excitations where the excited molecular states relax via kinetic arrangements of the nuclei [2]. We present experimental results of x-ray induced ring-opening and the subsequent fragmentation of organosulfur molecule, 2-Bromothiophene. The photoexcitation of the organic molecule is achieved through inner-valence ionization occurring at the bromine or sulfur atomic site. The fragmentation is revealed and identified via ion-ion coincidence measurements. We demonstrate that the carbon ring breaks up through multiple dual carbon-bond breaking channels, corresponding to multiple two-body dissociation pathways, such as [BrC_1,2,3, C_nH_n] and [BrCS, C₃H_n] ; the ring-opening leads to rich molecular fragmentation patterns where complexity of the energy and momentum rearrangement is indicated in light fragments. In addition, the results indicate isomerization to the bromine site associated with initial excitation at atomic bromine.