Femtosecond Time-Resolved Electron Ionization Mass Spectrometry

Abstract

Mass spectrometry, one of the most useful analytical tools in chemistry, remains a ‘black box,’ with molecules entering on one end and fragmented ions coming out the other end. This leaves one guessing what happens in between. In particular, one would like to know the reaction mechanisms that lead to the molecule-specific fragmentation patterns that are used for molecular identification. This research project will produce the needed time-resolved information in the same way that Femtochemistry has uncovered the fundamental steps between reagent and product in neutral compounds. Data from this work will be extremely valuable when compared to results from theory-based efforts aimed at understanding and predicting the fragmentation patterns occurring in mass spectrometry. Prediction of molecular fragmentation is essential because mass spectrometry libraries contain only a tiny fraction of all possible molecules. Beyond mass spectrometry, the proposed approach will enable studies of molecules, radicals, and multi-charged species far from equilibrium, such as those encountered in combustion, hypersonic flight, and in space. From the proposed measurements one will be able to determine intramolecular vibrational energy relaxation rates, uncover vibrational coherence, identify cases where reaction occurs prior to a statistical distribution of energy, and discover interesting new reaction mechanisms, such as those involving roaming radicals and neutral species.

Document Details

Document Type
DoD Grant Award
Publication Date
Mar 07, 2023
Source ID
FA95502110428

Entities

People

  • Marcos Dantus

Organizations

  • Air Force Office of Scientific Research
  • Michigan State University
  • United States Air Force

Tags

Fields of Study

  • Chemistry

Readers

  • Molecular Photonics/Laser Physics
  • Theoretical Analysis.

Technology Areas

  • Hypersonics
  • Hypersonics - Hypersonic Flight
  • Microelectronics
  • Space
  • Space - Hall-Effect Thruster