nanotimes News in Brief
10-09 :: September 2010
Water and Aqueous Ions // Innovative Measuring Chamber for X-ray Study of Liquid Jets
esearchers of Helmholtz-Zentrum Berlin have carried out an XES study of a free micro-liquid
jet on the synchrotron.
At Helmholtz-Zentrum Berlin (HZB), Germany, Prof. Dr. Emad Flear Aziz Bekhit, head of a junior research group, has shown that liquids can be inve- stigated by X-ray emission spectroscopy without using membranes after all. At the synchrotron sour- ce BESSY II, the group has built a special setup – the LiXEdrom. It is unique in that the liquid is shot as a jet through the X-ray beam. The jet from the nozzle becomes so thin and, at 80 metres per second, so fast that the vacuum can be maintained without the need of a membrane.
“On our LiXEdrom, we create a vacuum in the liquid chamber of up to 10-6 millibar, and can now per- form both absorption and emission measurements, giving us even more precise information about the structure of a material,” says Emad Aziz. It also allows a clear “view” of elements that possess absorption and emission energies similar to the energies of the membrane materials, and would therefore overlap with the membrane in the spectrum when measured. This concerns above all carbon and nitrogen – preci- sely those elements of interest in biological samples.
In their first measurements the group demonstrated they can achieve energy resolutions on their LiXEd-
rom comparable to those of the latest high resolution XES spectrometers. For water, they have proven that results obtained from an earlier setup were not over- lapped by disturbing membrane effects.
They have also studied the electronic structure of nickel ions, unhampered by a risk of deposits on a membrane wall distorting the results. For many ap- plications such as protein studies, this is a significant step towards obtaining reliable structural information.
In addition to those already mentioned, the research has involved Kathrin M. Lange, René Könnecke, Sa- mira Ghadimi, Ronny Golnak, Mikhail A. Soldatov, and Kai F. Hodeck, Alexander Soldatov.
Kathrin M. Lange, René Könnecke, Samira Ghadimi, Ronny Golnak, Mikhail A. Soldatov, Kai F. Hodeck, Ale- xander Soldatov and Emad F. Aziz: High resolution X-ray emission spectroscopy of water and aqueous ions using the micro-jet technique, In: Journal of Chemical Physics, Arti- cle in Print, DOI:10.1016/JChemPhys.2010.08.023: http://dx.doi.org/10.1016/j.chemphys.2010.08.023