Gas Phase Chemical Physics
The Gas Phase Chemical Physics (GPCP) program explores chemical reactivity, kinetics, and dynamics in the gas phase at the level of electrons, atoms, molecules, and nanoparticles. A continuing goal of this program is to understand energy flow and reaction mechanisms in complex, nonequilibrium, gas-phase environments. A new crosscutting theme for the GPCP program concerns systems chemistry, in which complex molecular behavior emerges from ensembles of molecules or large reaction networks in the gas phase. The GPCP program seeks to understand, model, and ultimately control this emergent molecular complexity. Of particular interest are gas phase and/or gas/surface chemical systems in which emergent behavior manifests as a significant and possibly precipitous change in chemical reaction rates, branching ratios, particle growth, and/or product energy distributions with changes in conditions, e.g. temperature, pressure, ion concentration (plasma) and reactions included in a reaction network..
Research supported by the program is detailed in five thrust areas:
- Light-Matter Interactions includes research in the development and application of novel tools, such as molecular spectroscopy, for probing the nuclear and electronic structure of gas-phase molecules to enable chemical and physical analysis of heterogeneous and dynamic gas-phase environments and to understand the dynamic behavior of isolated molecules, such as energy flow (e.g., relaxation of excited states) and nuclear rearrangements. Applications are encouraged that develop automated methods based on artificial intelligence and machine learning (AI/ML) methods to facilitate the analysis of complex molecular spectra or seek to improve the understanding of quantum phenomena.
- Chemical Reactivity comprises research in chemical kinetics and mechanisms, chemical dynamics, collisional energy transfer, and construction of, and calculations on, molecular potential energy surfaces to develop fundamental insight into energy flow and chemical reactions important in clean energy processes. This research also includes understanding the influence of nonequilibrium, heterogeneous, nanoscale environments on complex reaction mechanisms in chemical conversions. Applications are encouraged that develop AI/ML methods for the construction of potential energy surfaces and optimization of chemical kinetic mechanisms.
- Gas-Particle Interconversions comprises research on the chemistry of small gas-phase particles, including their interactions with gas-phase molecules and dynamic evolution to understand the molecular mechanisms of formation, growth, and transformation (such as evaporation, phase transition, and reactive processing) of small particles.
- Gas-Surface Chemical Physics retains a strong emphasis on molecular-scale investigations of gas-phase chemical processes with the goal of gaining a better understanding of the cooperative effects of coupling gas phase chemistry with surface chemistry.
- Ultrafast Imaging/Spectroscopy includes studies of the short timescale phenomena underlying photochemical and photophysical processes, such as photodissociation, isomerization, and nonadiabatic dynamics. Applications are encouraged that develop AI/ML methods for analyzing ultrafast images/spectra or to provide insight into chemical systems associated with clean energy.
Other areas of recent increased emphasis include benchmarking theoretical calculations via quantum state resolved experimental measurements of state-to-state chemical dynamics at conditions where quantum effects are significant, investigating the effect of non-thermal initial distributions on reaction dynamics, and understanding how complex reaction mechanisms transform over large temperature and pressure ranges.
The GPCP program does not support research in non-reacting fluid dynamics (transport phenomena including computational fluid dynamics), reacting and non-reacting turbulent flow and the impact of transport of chemical reactions, spray dynamics, data-sharing software development, end-use combustion device development, and characterization or optimization of end-use combustion devices.
To obtain more information about this research area, please see the proceedings of our Principal Investigators' Meetings. To better understand how this research area fits within the Department of Energy's Office of Science, please refer to the Basic Energy Science's organization chart and budget request.
For more information about this research area, please contact Dr. Wade Sisk.
