Binding energies in stretched graphitic systems: unusual van der Waals energy

  • Tim Gould, Griffith University, Australia
  • Prof Evan Gray, Griffith University, Australia
  • Mr Ken Simpkins, Nanoscale Science and Technology Centre, Griffith University, Australia
  • Prof John Dobsob, Griffith University, Australia

    • We present a theoretical and semiempirical investigation of the van der Waals energy in systems with multiple graphene layers. Such systems can be created by pillaring or intercalating graphite and are considered to be potential Hydrogen storage media. We show that the systems under consideration exhibit van der Waals power laws differing from those of metals and insulators and those used in previous ab initio and semiempirical methods. As the interlayer binding of such systems is weak, computational studies may run into difficulties without corrrections for the true van der Waals effects. To offset these difficulties we present a simple semiempirical method for use in these systems.