  Organometallic hexahapto chromium metal complexation of single layer
graphene, which involves constructive rehybridization of the graphene pi-system
with the vacant chromium d orbital, leads to field effect devices which retain
a high degree of the mobility with enhanced on-off ratio. This hexahapto mode
of bonding between metal and graphene is quite distinct from the modification
in electronic structure induced by conventional covalent sigma-bond formation
with creation of sp3 carbon centers in graphene lattice and this chemistry is
reversible.
