Related Experiment Video
Updated: Jul 12, 2026
16:11
Thermochemical Studies of Ni(II) and Zn(II) Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
Experimental Study of Collision-Induced Dissociation for Ionic Liquid Ions and Clusters
Stefan J Bell1, Abu Md Tahsin1, Elaine Petro1
1Department of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York14850, United States.
Journal of the American Society for Mass Spectrometry
|July 10, 2026
Summary
This study investigates the dissociation of ionic liquids used in satellite propulsion. We measured covalent dissociation energies and identified collision products, validating molecular dynamics simulations.
Area of Science:
- Physical Chemistry
- Space Propulsion
- Mass Spectrometry
Background:
- Electrospray ionization is crucial in mass spectrometry.
- The behavior of electrospray ions in satellite propulsion is not well understood.
- Ionic liquids are potential propellants, but their collisional dissociation needs characterization.
Purpose of the Study:
- To determine the covalent dissociation onset energy of common ionic liquids.
- To identify collision products from ionic liquid monomers and dimers.
- To validate molecular dynamics simulations using experimental data.
Main Methods:
- Tandem mass spectrometry (MS2) was employed.
- Experimentally measured detection fractions were recorded as a function of collisional energy.
- Molecular dynamics simulations were performed for comparison.
Main Results:
- Covalent dissociation onset energies for EMI-TFSI and EMI-BF4 were determined.
- Characteristic collision products for monomers and dimers (n=1 ion clusters) were identified.
- Experimental detection fractions were reported across a range of collisional energies.
Conclusions:
- This work provides critical data on ionic liquid ion dissociation under collisional conditions relevant to space propulsion.
- The findings validate the use of molecular dynamics simulations for predicting ion behavior.
- Understanding these processes is essential for developing advanced ionic liquid-based propulsion systems.
More Related Videos
Related Concept Videos
01:21Chemical Ionization (CI) Mass Spectrometry
The molecular ion peak of a molecule in the mass spectrum provides vital information for molecular identification. However, conventional electron impact ionization can lead to the rapid dissociation of some molecular ions before they reach the detector. A milder ionization method is required to increase the lifetime of such ionized analyte molecules. Chemical ionization (CI) is a gas-phase protonation reaction useful for mass-analyzing analyte molecules that are easily protonated to yield the...
01:28Ionic Association
The ionic association is the association of oppositely charged ions in an electrolyte solution to form ion pairs. Bjerrum defined ion pairs as two oppositely charged ions whose electrostatic attraction exceeds the thermal energy of the system, typically expressed as 2kT. Electrostatic attraction depends on ionic charge, separation distance, and the dielectric constant of the medium. Thermal energy, represented by kT, reflects the tendency of ions to move independently due to molecular motion.
03:13Intermolecular Forces
Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen bonds, and dispersion...
01:09Ion-Exchange Chromatography
Ion-exchange chromatography, or IEC, is a technique for separating ions based on their affinity for the stationary phase. The stationary phase is a cross-linked polymer resin with covalently attached ionic functional groups. The functional groups can be either positively charged (cation exchangers) or negatively charged (anion exchangers). A cation exchanger consists of a polymeric anion and active cations, while an anion exchanger is a polymeric cation with active anions. The choice of...
02:54Molecular and Ionic Solids
Crystalline solids are divided into four types: molecular, ionic, metallic, and covalent network based on the type of constituent units and their interparticle interactions.
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
01:22Mass Spectrometry: Alkyl Halide Fragmentation
Chlorine isotopes exist as 35Cl and 37Cl in a 3:1 ratio, while bromine isotopes exist as 79Br and 81Br in a 1:1 ratio. The mass spectrum of alkyl halides typically produces two distinct molecular ion peaks, the molecular ion peak, [M], and the molecular ion plus two, [M + 2] peak. The relative heights of these two peaks are proportional to the isotopic abundance ratios of the halide. For example, 2‐chloropropane and 1‐bromopropane display two peaks with relative peak heights in a 3:1 and 1:1...