Physicists from the Institute of High Pressure Physics at the Russian Academy of Sciences have created a magnet consisting purely of carbon. The magnet is said to have retained strong magnetic properties up to 230 degrees Centigrade.
‘We studied transformations of fullerene C60 at high pressures and temperatures and synthesised a series of materials which surprisingly happened to be magnets’, said Valery Davydov, head of the Troitsk research group, of the serendipitous discovery.
The new material is said to consist of rhombohedral polymerised phase of fullerene C60. It has graphite-like lamellar structure; the difference is that in graphite C atoms form the layers, whereas in the new material they are formed by C60 molecules.
To make carbon magnetic, the physicists placed a sample under pressure of 60,000 atmospheres and heated it up to 700-800 degrees C.
The scientists initially tried to explain the magnetic properties through the effects of metallic impurities. In collaboration with researchers from Sweden, Germany and Brazil, they studied new series of samples in detail and proved that the content of metallic impurities was extremely low, so it could not result in the observed magnetism.
They concluded that the carbon material acquired strong magnetic properties during the high-pressure thermal processing.
The scientists have no clear explanation for the discovered effect of carbon magnetising. One possible explanation involves spins of unpaired electrons, which could be oriented in one direction and impart magnetic properties to the carbon material.