October 3, 2008: Virginia Tech chemistry professor Harry Dorn has developed a new area of fullerene chemistry that may be the backbone for development of molecular semiconductors and quantum computing applications.

In his work with hollow carbon molecules known as fullerenes, Dorn placed gadolinium atoms inside the carbon cage for MRI applications, creating an 80-atom carbon molecule with two yttrium ions inside. Then he replaced one of the 80 atoms of carbon with an atom of nitrogen (providing Y2@C79N). This change leaves the nitrogen atom with an extra electron. Dorn discovered that the extra electron, instead of being on the nitrogen atom on the fullerene cage surface, ducks inside between the yttrium ions, forming a one-electron bond.

“Basically, a very unusual one electron bond between two yttrium atoms,” he said.

Discovery of this new class of stable molecules (M2@C79N ) was supported by computational studies by Daniel Crawford, associate professor of chemistry at Virginia Tech, and the structure was confirmed by X-ray crystallographic studies by Alan Balch, professor of chemistry at the University of California, Davis.

This research is reported in the Sept. 6, 2008, online issue of the Journal of the American Chemical Society.

“No one has done anything like this,” said Dorn. “Since the article was published, we now know that we can take the electron back out of the fullerene cage.”

He said the discovery could be important to the new fields of spintronics, molecular electronics, and micro to nanoscale electronics, as well as the new field of quantum computing.

“The single electron bonded-diatomic yttrium has unique spin properties that can be altered. Increasing the polarization of this spin, could be important for improving the sensitivity of MRI and NMR (nuclear magnetic resonance),” he said.

But more interesting are the electronic applications. “If we replace one of the carbon atoms with boron instead of nitrogen, we would be an electron short, instead of having an extra electron. Now you have the components of a semiconductor,” Dorn said.