The discovery, led by Associate Professor Brian Abbey at La Trobe in collaboration with Associate Professor Harry Quiney at the University of Melbourne, was made using the world's first hard X-ray free- electron laser (XFEL), based at Stanford University in the United States.
Scientists have inadvertently discovered how to create a new type of crystal using light more than ten billion times brighter than the sun. (Image Credit: Australian Research Council Center of Excellence for Advanced Molecular Imaging)
The light from the XFEL is about one billion times brighter than light generated by any other X-ray equipment.
The team decided to expose a sample of crystals, known as Buckminsterfullerene or Buckyballs, to this intense light. The molecules have a spherical shape forming a pattern that resembles panels on a soccer ball.
Because any other X-ray sources used in previous research deliver their energy much slower than the XFEL, all of the previous observations had determined that the X-rays randomly melt or destroy the crystal. Therefore scientists had assumed that XFELs would do the same.
However the results from the XFEL experiments were not what they had expected. When the XFEL intensity was cranked up past a critical point, the electrons in the Buckyballs spontaneously re-arranged their positions, changing the shape of the molecules completely.
All of the molecules in the crystal changed from being shaped like soccer balls to being shaped like American footballs at the same time. This effect produces completely different images at the detector and alters the sample's optical and physical properties.
"It was like smashing a walnut with a sledgehammer and instead of destroying it and shattering it into a million pieces, we instead created a different shape—an almond!" said Abbey.
According to Quiney, even though it only remains stable for a tiny fraction of a second, the team was able to observe that the sample's physical, optical and chemical characteristics changed dramatically from their original form.
"This change means that when we use XFELs for crystallography experiments, we will have to change the way we interpret the data. The results give the 100-year-old science of crystallography a new, exciting direction," added Abbey.
Crystallography is currently used by biologists and immunologists to investigate the inner workings of proteins and molecules. According to the researchers, the ability to see these structures in new ways will help to understand interactions in the human body and could even open new avenues for drug development.
