Binding Energy
- Practical Electron Microscopy and Database -
- An Online Book -

http://www.globalsino.com/EM/  



 

This book (Practical Electron Microscopy and Database) is a reference for TEM and SEM students, operators, engineers, technicians, managers, and researchers.

 

=================================================================================

Figure 3959a shows the generation of secondary electrons (SEs) and kinetic energies of the emitted SEs. EKE1 and EKE2 represent the kinetic energies of the two generated SEs. The kinetic energy of the generated SEs is normally in the range of 0 to 50 eV. ΔE1 and ΔE2 represent the energy losses of the incident electrons after the incident electrons interact with the electrons in the K and L3 subshells, respectively. E1 and E2 are the binding energies of the two electrons. E0 is the energy of the incident electrons in the EMs.

The generation of secondary electrons (SEs) and kinetic energies of the emitted SEs 

Figure 3959a. The generation of secondary electrons (SEs) and kinetic energies of the emitted SEs.

The shell electrons are bound to atoms by what is called binding energy. The binding energy of each shell is the minimum energy, which an incoming electron or photon must have to be able to ionize the atom. The strongest binding energy is the K-shell binding energy and the binding energies get weaker for the the further electron from the nucleus. Moreover, the binding energies increase with the atomic number of the nucleus as indicated by the examples in Table 3959.

Table 3959. K-Shell Binding Energy for Various Elements

Element
Atomic Number (Z)
Binding Energy (keV)
Oxygen 8 0.5
Calcium 20 4.0
Iodine 53 33
Barium 56 37
Tungsten 74 69.5
Lead 82 88

Figure 3959b shows the relation between electron binding energies, atomic number (Z) and electronic transition. In the figure, the same colors shows the curves and corresponding electronic transitions. Figure 3959c shows the details of the relation between electron binding energies and atomic number (Z) at low binding energies.

Relation between electron binding energies, atomic number (Z) and electronic transition

Figure 3959b. Relation between electron binding energies, atomic number (Z) and electronic transition.

Relation between electron binding energies and atomic number (Z)

Figure 3959c. Relation between electron binding energies and atomic number (Z) (at low binding energies).

 

=================================================================================

The book author (Dr. Liao) welcomes your comments, suggestions, and corrections, please click here for submission. You can click How to Cite This Book to cite this book. If you let Dr. Liao know once you have cited this book, the brief information of your publication will appear on the “Times Cited” page. This appearance can help advertise your publication.



 
 
 
Copyright (C) 2006 GlobalSino, All Rights Reserved