Carbon disulfide (CS2), a non-metallic solvent and insecticide, was not thought to act as a superconductor, but the substance is even more conductive to electricity than traditional materials.
Superconductors are materials which offer no resistance to electricity. Their molecules are usually highly-organized, and closely-packed. They can be created from some materials which are subjected to extreme cold and pressure. Should a practical room-temperature superconductor be developed, it could lead to magnetic levitating trains, ultra-fast computers, nuclear fusion and an electrical transmission grid without energy loss.
Choon-Shik Yoo, a chemistry professor at Washington State University, led the study of the solvent with researchers from Carnegie Institution. His team found that as CS2 is subjected to cold and high pressures, the molecules arrange into a lattice structure, like diamonds, and the material begins to exhibit metal-like properties, including magnetism. The vibrations of the molecules in this formation also assist in eliminating electrical resistance.
To achieve these properties, Yoo chilled the samples down to -447 degrees Fahrenheit and compressed them, using a diamond anvil cell, to a pressure of 50,000 atmospheres. This is the same as the pressure present 600 feet beneath the surface of the Earth, or over 3,300 times as powerful as a pressure cooker.
At these temperatures and pressures, the molecules in the CS2 were close enough together that electricity could flow through the material. In most non-metals, the particles are too far apart to allow the flow of energy.
"It is an important discovery that will attract a lot of attention from many scientific communities - physics, chemistry, and materials science," Yoo said.
This line of research developed from the work of one of Yoo's doctoral students, Ranga Dias.
It is unlikely that such superconductors will be commercially viable as long as they need to be kept at such extreme temperatures and pressures. However, this new research could open up new information about superconductivity in non-traditional materials.
"This research will provide the vehicle for people to be clever in developing superconductors by understanding the fundamentals that guide them," Yoo said.
The study was published in the journal Proceedings of the National Academy of Science (PNAS) on July 1, 2013.
