ARCHIVED - Breakthrough Motion Imaging of Atoms in Molecules

Archived Content

Information identified as archived is provided for reference, research or recordkeeping purposes. It is not subject to the Government of Canada Web Standards and has not been altered or updated since it was archived. Please contact us to request a format other than those available.

April 03, 2003— Ottawa, Ontario

NRC Movie features Atoms in the Starring Role

NRC scientist observing femtosecond pulses.Dr. Hiromichi Niikura and his team of scientists NRC Steacie Institute for Molecular Sciences (NRC-SIMS) recently achieved a major scientific breakthrough, successfully tracking the motion of hydrogen atoms in a hydrogen molecule. The results are contained in a paper recently published in the February 20th issue of Nature.

Many scientists around the world are striving to capture the motion of atoms in molecules. However, the quest has proven quite difficult for several reasons. The atoms in a molecule are packed so close together that phenomenal resolution is required to "see" them. Lighter atoms that move faster also make tracking difficult.

The frames in Dr. Niikura's "movie" are separated by about 1/50 of the vibrational period of the molecule (200 attoseconds) and the resolution of the image is about 1/50 of the separation between the atoms (0.02 Angstroms).

To make the movie, Dr. Niikura and his co-workers use a very unusual "flash." They use electrons taken from the hydrogen molecules themselves. An intense laser beam pulls the electron free of the molecule and away from its parent ion, but when the electric force of the light wave reverses direction, the electron is forced back and collides with the molecule. The "collision" is what snaps the picture. In Dr. Niikura's movie, the electron collision is delayed for each successive frame. He dials in the delay by changing the laser wavelength.

Project Leader Dr. Paul Corkum of NRC-SIMS points out that NRC, in collaboration with researchers from the University of Sherbrooke, is building on advances by the team earlier this year. In the first paper, also featured in Nature, the group was able to measure the duration and magnitude of the electron "flash." Findings also suggested the promise that electrons could be used for precision imaging, something that had never been accomplished. Dr. Corkum and his colleagues are very proud that this "dream" of eight months ago has now rapidly become a reality.

Enquiries: Media relations
National Research Council of Canada

Stay connected


Date modified: