Recently, scientists at the university of Oklahoma in the us have suggested that graphene may have a class of three-dimensional heterotype belonging to a new family. These structures are likely to be synthesized in the experiment, and the simplest “supercellular” structure has many unusual properties that may be more stable than diamond. Graphene is a two-dimensional, hexagonal structure that connects each carbon atom to three other carbon atoms. This “planar triangular connection” gives it many unique properties, especially electrical properties, making it an excellent semiconductor material . The triangular connection of graphene can produce unusual phenomena: The energy that causes the electron changes linearly with its momentum, causing the electron to appear motion similar to the speed of light. The Dirac equation describes this relativistic electron, so the value of the momentum in this behavior is known as the “Dirac point.” Most material structures do not have a Dirac point. This linear behavior will greatly affect electron distribution and their interaction with lattice vibrations. The researchers wanted to know what would happen if the Dirac point on a carbon base plane triangle was expanded to three dimensions. The Dirac ring has not been observed in the experiment so far, but it is only predicted to exist in a few subtle materials. According to the analysis, when the triangle connects the carbon chain to each other, it can theoretically form the Dirac ring. This arrangement is different from graphite, which is also a 3D structure, but is stacked on top of each other. The vertical stack chain has many different dimensions, because the honeycomb hexagon has many possibilities in the vertical and horizontal combination. Like the simplest super-cellular structure, only two carbon atoms are perpendicular to each other, and the lattice is a little like a tiny double-sided bookcase.
“Our research has two implications,” said Kieran Mullen of the university of Oklahoma. “First of all, this is the first simple system to show the Dirac ring. The Dirac ring is a property that has not yet been seen in the electronic system, and has a significant impact on the way electrons flow through the system and their behavior in the magnetic field. Second, the system will bring a lot of related systems, some are other carbon structure, some of them are similar in different physical systems, such as the cold gas atomic optical lattice, may also find more unusual nature.” The 3D structure may make the
supercellular allotrope extremely stable, even more than diamond and graphite.” We are trying to calculate the hardness (tensile strength) and strength (breaking resistance),” Mullen said. They predicted that it would be a big challenge to synthesize the new family, but it is possible to use the current technology.
