Monolayer Skin Entrapment Without Polarization

Bonds between undercoordinated C atoms are shorter and stronger than that inside the bulk graphite. 

Bonds at edges of defects of GNR are even shorter and stronger because of one more neighbor loss. 

The edge dangling-cr-bond electrons in the vacant and ZGNR edge are polarized by electrons that are densely entrapped in the core and bonding orbits, which create the high STM protrusions and the resonant Dirac-Fermi states at 

The polarons screen and split the local interatomic potential, resulting in the entrapped T and the polarized P states in the Cls band. 

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Figure 13.8d compares the ZPS profiles of the monolayer skin and the vacancy defect of graphite. The skin ZPS shows only one entrapment without polarization, which is the same to the ZPS of Pt adatoms. However, the defect ZPS shows an entrapment peak that is even lower in energy and an additional polarization peak, which is similar to the Rh adatoms and W edges. A combination of the STM/S and the ZPS profiles provides a comprehensive picture on what has happened to the monolayer skin and the point defect of graphite, and the GNR edges ... 

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