Seeing real time bond formation
25 Mar 2015 by Evoluted New Media
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Researchers have visualised real time bond formation in an entire chemical reaction.
Chemists at the Institute for Basic Science for Nanomaterials and Chemical Reactions in South Korea used X-ray free-electron lasers to observe bond formation of a gold trimer complex in solution on a femtosecond scale (10?15 of a second).
“This work demonstrates that it is possible to track in detail and in real time the structural changes that occur during a chemical reaction in solution using X-ray free-electron lasers and advanced analysis of time-resolved solution scattering data,” said the research team in the study.
The scientists observed light induced bond formation between gold atoms dissolved in water and visualised a sequence of structural changes such as covalent bond formation, bond contraction and tetramer formation with a time resolution of approximately 500 femtoseconds.
The team managed to overcome diffusion of the reaction by using femtosecond time-resolved X-ray liquidography (femtosecond TRXL) and study the structural dynamics of bond making.
“It is especially difficult to initiate and follow diffusion-limited bond formation in solution with ultrahigh time resolution. Here we use femtosecond TRXL scattering to visualise the formation of a gold trimer complex, in real time,” the researchers said in their paper.
The study, published in Nature, also determined the three-dimensional structures of the reaction intermediates with by applying a spatial resolution known as sub-ångström.
The research leader Professor Hyotcherl Ihee said: “By using femtosecond TRXL, we will be able to observe molecular vibration and rotation in the solution phase in real time”.
Paper: http://www.nature.com/nature/journal/v518/n7539/full/nature14163.html