Transferable potential for carbon without angular terms

A simple transferable potential for carbon is developed for use in atomistic simulation. It describes all the phases of carbon, from the close packed, such as face centered cubic, to the open systems, such as diamond cubic, graphite, and even linear chains. The parameters are fit to a total-energy local-density functional theory database augmented by the known cohesive energies of diamond and graphite. Further, structures such as simple molecules, not in the database, are well described. For example, it predicts that odd number of atom molecules form chains whereas even atom number molecules form rings. The diamond cubic and graphitic structures are dynamically stable. The formalism also allows for interaction with an external electric field. Further, it can be generalized to other covalent systems as well as mid-d-block elements.