Mechanical properties of monolayer graphene under tensile and compressive loading

The mechanical properties of zigzag graphene and armchair graphene nanoribbon under tensile and compressive loading are studied by the use of quantum mechanics as well as quantum molecular dynamics (MD) method based on the Roothaan-Hall equation and the Newton motion laws. The similar failure mechanisms and different mechanical properties are found in zigzag graphene and armchair graphene subjected to mechanical load. Under tensile or compressive loadings, the critical loading of the zigzag graphene is larger than that of the armchair graphene. Both zigzag graphene and armchair graphene begin to break at the outmost carbon atomic layers. Applied mechanical loading indeed changes the electronic properties of graphene. (C) 2009 Elsevier B.V. All rights reserved.