Science paper for Weinstein and Meijer groups 

AnimationResults published in Science on 19 December report on the common elementary reaction of electron transfer and how lasers at STFC have been used to direct the result of a specific light-induced process away from a particular outcome.

The work looks at what has often been deemed the “holy grail” of chemistry, whereby light is not only used to start a chemical reaction, for example photosynthesis, but also to actually control which products are formed.

Chemical reactions generally run from reactants to products and whilst usually a single product is made, the journey involves several steps and intermediates where the reaction will generally the most favoured route. This latest result from the Weinstein group working with the STFC Central Laser Facility shows how using an invisible, low-energy “infrared” light – like that used in night-vision cameras – can radically change which products are formed, when a specific organometallic compound (synthesized by dr. Paul Scattergood) interacts with light. When a laser pulse triggers a reaction, the natural product will be created but using a second, infrared, laser pulse the molecule is directed to change from its normal path to form a different product. These intricate experiments, which were performed by dr. Milan Delor, were backed up by calculations from the Meijer group, which also show this pathway switch.

For more information, see the STFC press release or the Science paper itself.

There is also an item on this paper in the March 2015 issue of Physics Today. For more details see here.