Long-range Interactions in Graphene (IMAGE) DOE/Lawrence Berkeley National Laboratory Caption Undoped graphene isn't a metal, semiconductor, or insulator but a semimetal, whose unusual properties include electron-electron interactions between particles widely separated on graphene's honeycomb lattice -- here suggested by an artist's impression of the Feynman diagrams often used to keep track of such interactions. Interactions occur over only very short distances in ordinary metals. Long-range interaction alter the fundamental character of charge carriers in graphene. Credit Image by Caitlin Youngquist, Lawrence Berkeley National Laboratory Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.