Quantifying Collisional Energies within an Ion Trap Mass Spectrometer by LabVIEW Simulation
The energetics involved in chemical reactions and the bond energies of ions are of fundamental importance to the field of chemistry. Conventional methods of collision induced dissociation (CID) within an ion trap mass spectrometer provide invaluable structural information on the ions in question. However, the energy imparted on the ions following repeated collisions with a neutral gas often remains ambiguous and unexplored. These energies are often simply represented by a unit less quantity (such as normalized collisional energy, NCE %) instead of an absolute energy unit. In an effort to clarify this ambiguity, we herein present a LabVIEW simulation combined with mass spectrometry experiments which will allow both experimentalist and theoretical chemists alike to develop a more intuitive understanding of the collision energetics within an ion trap mass spectrometer. An experimental calibration of collision energy is conducted by performing CID on a series of ions with well-known bond energies. Next, a LabVIEW simulation is implemented and compared to the experimental observations to test its accuracy. The collisional energy distributions are quantified from the velocity distributions of the simulated ion trajectories. The collisional energy distribution calculated the most probable energy of collisions within of the published bond energy metrics. Herein, an efficient method for understanding the collision energetics within an ion trap mass spectrometer during CID is presented.
Faculty Mentors: Michael P. Grubb, Callie A. Cole