2024-03-29T09:06:13Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/27572017-02-23T08:58:50Zcom_10261_89com_10261_3col_10261_342
2008-01-29T13:44:55Z
urn:hdl:10261/2757
Strong covalent bonding between two graphene layers
Andrés, Pedro L. de
Ramírez, Rafael
Vergés, José A.
few graphene layers
We show that two graphene layers stacked directly on top of each other (AA stacking) form strong chemical bonds when the distance between planes is 0.156 nm. Simultaneously, C-C in-plane bonds are considerably weakened from partial double-bond (0.141 nm) to single bond (0.154 nm). This polymorphic form of graphene bilayer is meta-stable w.r.t. the one bound by van der Waals forces at a larger separation (0.335 nm) with an activation energy of 0.16 eV/cell. Similarly to the structure found in hexaprismane, C forms four single bonds in a geometry mixing 90 and 120 angles. Intermediate separations between layers can be stabilized under external anisotropic stresses showing a rich electronic structure changing from semi-metal at van der Waals distance, to metal when compressed, to wide gap semiconductor at the meta-stable minimum.
2008-01-29T13:44:55Z
2008-01-29T13:44:55Z
2008-01-14
artículo
Phys Rev B 77 (4) 045403 (2008)
http://hdl.handle.net/10261/2757
eng
openAccess
American Physical Society