Potential energy surfaces of mechanically induced reconstruction and doping of carbon sp2 lattice

Potential energy surfaces of mechanically-induces structural failure and doping by silicon atom of graphene armchair nanoribbon (14 carbon dimers width, 14-AGNR) are studied by ab initio GGA LC DFT technique in combination with Gaussian-type basis set and periodic boundary conditions. Application of external force to a central atom of a perfect graphene nanoribbon leads to ejection of a carbon dimer or pulling out a polycumulene chain. Different mechanisms of mechanical substitution of carbon dimers by eta(2) coordinated silicon are studied. Migration of silicon adatom on graphene and embedding the atom into the lattice at the vicinity of divacancy induces formation of diamagnetic sp(2)d rectangular planar silicon dopant center. PES of formation of sp(2)d silicon center consists of several relatively low potential energy barriers, making possible a synthesis of novel 2D materials with unique physical properties. (C) 2016 Elsevier B.V. All rights reserved.