Until now, the idea of controlling reactions with the light from lasers was only theoretical. However, new research shows that a laser pulse has the ability to control the formation of a molecular bond between two atoms.
Due to this new development, researchers can now control the path of the chemical process with extreme precision.
This from APS Physics:
For the first time, researchers demonstrate the coherent control of the reaction by which two atoms form a molecule. The achievement—coupled with other photocatalyst tools—could potentially lead to a chemical assembly line, in which lasers slice and weld molecular pieces into a desired end product.