Workshop on Spectroscopy of Chemical Reactions in Gases and Plasmas

Thursday, Feb. 20, 2014
Berlin-Adlershof, HZB, BESSY II


Chemical reactions of atoms and molecules in the gas phase or in plasmas define manifold techno-logical processes from the operation of jet engines to plasma cleaning or spraying deposition.

To understand the chemical reactions that lead to the decomposition and oxidation of a fuel, specially tailored flames are used that are accessible to quantitative measurement techniques capable to follow the reaction process in detail. Several hundred reactions can contribute even to the combustion of such a simple fuel as methane. Many intermediate species, often radicals, may have to be quantitatively detected within the reactive combustion mixture, and since these species are typically represented in small concentrations (often at the ppm level or below) this is a demanding analytic task.

Achieving high efficiency and low pollutant emissions simultaneously is an enormously demanding task for modern combustion research. New developments affect not only the technical design of combustion processes in gas turbines, power plants and engines. Especially the formation of pollutants and the development of concepts that reduce undesired and harmful emissions need detailed information on the chemistry of combustion processes.

Laser-induced fluorescence and cavity ring-down spectroscopy provide quantitative concentrations of many small intermediates. In in-situ molecular beam mass spectrometry, the ionization of the molecules is performed with electron impact or with photons, using laser or synchrotron radiation.

Photoionization with synchrotron radiation for the mass spectrometric detection of gas composition represents a cornerstone in analytical chemistry research in gases and plasmas. The photon energy from these radiation sources in the range of about 6-20 eV can be tuned with a resolution of about 40 meV. It can thus be matched to the ionization thresholds of nearly all chemical species in the gas flames.

The current workshop will discuss current state of chemical analysis and reaction kinetics probed with synchrotron and laboratory based methods in gases and plasmas and will emphasize on future opportunities using soft x-ray synchrotron radiation in this field of research.