(1) Perturbation to the Hamiltonian by atomic undercoordination-induced bond
contraction, the hetero-coordination-induced bond nature alteration, and the
polarization of the nonbonding electrons dictate intrinsically the electron
binding energy shift of the irregularly coordinated systems.
(2) Core electron entrapment and nonbonding electron polarization take place by
atomic and molecular undercoordination, tetrahedral bond formation, and heterocoordination. The local charge densification and quantum entrapment result in
the globally positive core level shift, which is proportional to the local bond
energy.
(3) Polarization of the nonbonding states pertained to the outermost shell of the
even fewer coordinated edge or surface atoms by the locally densely entrapment bonding electrons negatively offsets the entrapped states and raises the
local Fermi energy, or creates the polarized states above the E F .
(4) Water molecular undercoordination and ionic electrostatic polarization have the
same effect on O:H–O bond relaxation, O 1s electron entrapment, and valence
electron polarization. Being similar to the APECS, the NEXAS pre-edge shift
results from the combination of the core level and the valence band shifts,
which fingerprints less sensitively the bond relaxation and polarization than the
XPS.
The dominance of valence electron entrapment of Pt adatoms and Cu/Pd alloy
ensures their acceptor-type catalysts, while the polarization dominance of Rh
adatoms and Ag/Pd alloy endows their donor-type catalysts. It is the right entrapment or polarization dictates the single-atom catalysis. The isolation and polarization of the dangling r bond electrons by the densely, locally entrapped bonding
electrons surrounding the defects and at the zigzag edges create the graphitic
Dirac-Fermi polaritons of graphene ribbons. Only one atomic neighbour loss
transits the entrapment dominance of the smooth graphite skin to the polarization
dominance of its point defect. It is suggested that the spin-coupled nonbonding
electron polarization by atomic undercoordination and sp orbital hybridization
dictate the skin dominance of monolayer high-T C superconductivity and the
topological insulator edge superconductivity.
Part II deals with the very low energy electron diffraction (VLEED), specifically
by the O–Cu(001) surface reaction. Interplaying with STM/S and PES, VLEED
probes the behaviour of atoms, bond geometry, and bonding dynamics in the
outermost two atomic layers and their electrons in the valence band and above,
which reveals dynamic information about the bond formation and relaxation,
valence energy states, and potential barrier shape evolution. VLEED determines the
variation of work function, atomic muffin-tin inner potential constant, the first two
Brillouin zones, and the effective mass of electrons near the Brillouin zone
boundaries. Most strikingly, the exposure-resolved VLEED clarifies the creation of
four valence states of the bonding pairs, nonbonding lone pairs, ionic electronic
holes, and antibonding dipoles associated with the four-stage bonding transition
dynamics from the CuO 2 pairing pyramids to the Cu 2 O 3 pairing tetrahedrons:
Preface
xi
contraction, the hetero-coordination-induced bond nature alteration, and the
polarization of the nonbonding electrons dictate intrinsically the electron
binding energy shift of the irregularly coordinated systems.
(2) Core electron entrapment and nonbonding electron polarization take place by
atomic and molecular undercoordination, tetrahedral bond formation, and heterocoordination. The local charge densification and quantum entrapment result in
the globally positive core level shift, which is proportional to the local bond
energy.
(3) Polarization of the nonbonding states pertained to the outermost shell of the
even fewer coordinated edge or surface atoms by the locally densely entrapment bonding electrons negatively offsets the entrapped states and raises the
local Fermi energy, or creates the polarized states above the E F .
(4) Water molecular undercoordination and ionic electrostatic polarization have the
same effect on O:H–O bond relaxation, O 1s electron entrapment, and valence
electron polarization. Being similar to the APECS, the NEXAS pre-edge shift
results from the combination of the core level and the valence band shifts,
which fingerprints less sensitively the bond relaxation and polarization than the
XPS.
The dominance of valence electron entrapment of Pt adatoms and Cu/Pd alloy
ensures their acceptor-type catalysts, while the polarization dominance of Rh
adatoms and Ag/Pd alloy endows their donor-type catalysts. It is the right entrapment or polarization dictates the single-atom catalysis. The isolation and polarization of the dangling r bond electrons by the densely, locally entrapped bonding
electrons surrounding the defects and at the zigzag edges create the graphitic
Dirac-Fermi polaritons of graphene ribbons. Only one atomic neighbour loss
transits the entrapment dominance of the smooth graphite skin to the polarization
dominance of its point defect. It is suggested that the spin-coupled nonbonding
electron polarization by atomic undercoordination and sp orbital hybridization
dictate the skin dominance of monolayer high-T C superconductivity and the
topological insulator edge superconductivity.
Part II deals with the very low energy electron diffraction (VLEED), specifically
by the O–Cu(001) surface reaction. Interplaying with STM/S and PES, VLEED
probes the behaviour of atoms, bond geometry, and bonding dynamics in the
outermost two atomic layers and their electrons in the valence band and above,
which reveals dynamic information about the bond formation and relaxation,
valence energy states, and potential barrier shape evolution. VLEED determines the
variation of work function, atomic muffin-tin inner potential constant, the first two
Brillouin zones, and the effective mass of electrons near the Brillouin zone
boundaries. Most strikingly, the exposure-resolved VLEED clarifies the creation of
four valence states of the bonding pairs, nonbonding lone pairs, ionic electronic
holes, and antibonding dipoles associated with the four-stage bonding transition
dynamics from the CuO 2 pairing pyramids to the Cu 2 O 3 pairing tetrahedrons:
Preface
xi