An ultrafast "electron camera" at the Department of Energy's SLAC National Accelerator Laboratory at Stanford University has taken the first direct snapshots of atomic nuclei in molecules that are vibrating within millionths of a billionth of a second after being hit by a laser pulse. The method they used is called ultrafast electron diffraction (UED).Researchers used the UED instrument's electron beam to look at iodine molecules at different points in time after the laser pulse. By stitching the images together, they obtained a "molecular movie" that shows the molecule vibrating and the bond between the two iodine nuclei stretching almost 50% - from 0.27 to 0.39 millionths of a millimeter - before returning to its initial state. One vibration-al cycle took about 400 femtoseconds.
展开▼
