Seeing real time bond formation

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