Experimental Study of Collision-Induced Dissociation for Ionic Liquid Ions and Clusters

Electrospray ionization is well established in mass spectrometry, but the collisional behavior of electrospray ions in the context of satellite propulsion systems remains poorly understood. This work demonstrates the covalent dissociation onset energy for commonly used ionic liquids, 1-ethyl 3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMI-TFSI) and 1-ethyl 3-methylimidazolium tetrafluoroborate (EMI-BF 4 ), using tandem mass spectrometry (MS2). Characteristic collision products are identified for each ionic liquid and for their n = 1 ion clusters (dimers). Additionally, experimentally measured detection fractions for each dissociation product are reported as a function of the lab-frame collisional energy. The experimental results are compared with molecular dynamics simulations to provide a validation case for the simulation results.