Wednesday, September 15, 2010
I think this kind of stuff is unbelievably cool,
By timing the oscillations between valence electrons through a process called attosecond absorption spectroscopy, scientists were able to use ultra short flashes of laser light( cycles lasting around a quadrillionth of a second) to directly observe the movements of an atom's outer electrons for the very first time.
Using an infra red laser pulse researchers first ionized Krypton (yes it's a real element) atoms causing them to loose one to three electrons from their outer shell. They then used a second extreme-ultraviolet pulse on the same path as the first to excite electrons in the next energy orbital beneath the outer most shell causing them to jump to the outer orbit filling the gaps created by the first pulse. This in turn, caused the electrons to begin switching between the two orbits, creating a complementary interference pattern which scientists were then able to directly measure and observe.
For more technical information on this story check out the following article from io9 or the original article directly from the Berkley Lab web page.