3.5 ZPS: Atomic CN-Resolved Bond Relaxation
55
3.5.2 Quantitative Information
The ZPS distils the DOS gain as components presenting above the lateral axis and
features the DOS loss as valleys below the lateral axis. This process removes the
commonly shared spectral area that provides little useful information. Ideally, the
resultant ZPS components conserve as the spectral areas above and areas below
the lateral axis are identical. Any improper background correction or spectral normalization may asymmetrize the spectral gain and loss compared with the ideal
situation. With these criteria, one can readily gain quantitative information of local
bond length, bond energy, charge entrapment and polarization, etc., under various
working conditions.
Conventionally, one needs to correct the spectral background using the standard
Tougaard method [28–30] by employing Gaussian-, Lorentz-, or Doniach-Sunjictype functions before decomposing the XPS profiles. However, ZPS saves such
tedious procedures of background correction, component specification, and peak
energy fine-tuning. ZPS gives directly the skin or conditioned component as emerging
peaks and the bulk component as valleys.
3.6 Summary
Complementing the STM/S and PES, the ZPS resolves directly the local bond relaxation and the associated CLS and valence charge evolution without involvement of
trial-error optimization in analyzing the coordination effect. Extracted information
includes the local binding energy density, atomic cohesive energy, charge quantum
entrapment and polarization, energy level of an isolated atom. Reformulation of the
APECS derive the energy shift of two energy levels simultaneously with provision
of the coefficients of charge sharing and potential field screening. It is particularly
rectified that the shift of Auger parameter equals twice of the shift of the upper energy
level instead of the sum of both the deeper and the upper levels. The involvement
of the atomic CN effect results in the quantitative information on the screening and
charge transporting information of the specimen. The XAS pre-edge shift results
from the resultant of the dual level shift of the core band and the valence band.
The XAS pre-edge shifts by a perturbation always in an opposite direction of the
single XPS core level. The combination of the STS, XAS, ZPS, and APECS empowers the currently available spectroscopic techniques to resolve the atomistic, local,
dynamic and quantitative information on bond relaxation and the associated energetics of bonding and nonbonding electrons pertaining to irregularly-coordinated atoms.
Interplay of these spectrometric techniques would be more revealing than using any
of them alone.
55
3.5.2 Quantitative Information
The ZPS distils the DOS gain as components presenting above the lateral axis and
features the DOS loss as valleys below the lateral axis. This process removes the
commonly shared spectral area that provides little useful information. Ideally, the
resultant ZPS components conserve as the spectral areas above and areas below
the lateral axis are identical. Any improper background correction or spectral normalization may asymmetrize the spectral gain and loss compared with the ideal
situation. With these criteria, one can readily gain quantitative information of local
bond length, bond energy, charge entrapment and polarization, etc., under various
working conditions.
Conventionally, one needs to correct the spectral background using the standard
Tougaard method [28–30] by employing Gaussian-, Lorentz-, or Doniach-Sunjictype functions before decomposing the XPS profiles. However, ZPS saves such
tedious procedures of background correction, component specification, and peak
energy fine-tuning. ZPS gives directly the skin or conditioned component as emerging
peaks and the bulk component as valleys.
3.6 Summary
Complementing the STM/S and PES, the ZPS resolves directly the local bond relaxation and the associated CLS and valence charge evolution without involvement of
trial-error optimization in analyzing the coordination effect. Extracted information
includes the local binding energy density, atomic cohesive energy, charge quantum
entrapment and polarization, energy level of an isolated atom. Reformulation of the
APECS derive the energy shift of two energy levels simultaneously with provision
of the coefficients of charge sharing and potential field screening. It is particularly
rectified that the shift of Auger parameter equals twice of the shift of the upper energy
level instead of the sum of both the deeper and the upper levels. The involvement
of the atomic CN effect results in the quantitative information on the screening and
charge transporting information of the specimen. The XAS pre-edge shift results
from the resultant of the dual level shift of the core band and the valence band.
The XAS pre-edge shifts by a perturbation always in an opposite direction of the
single XPS core level. The combination of the STS, XAS, ZPS, and APECS empowers the currently available spectroscopic techniques to resolve the atomistic, local,
dynamic and quantitative information on bond relaxation and the associated energetics of bonding and nonbonding electrons pertaining to irregularly-coordinated atoms.
Interplay of these spectrometric techniques would be more revealing than using any
of them alone.