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Electron binding energy

  1. Jan 17, 2006 #1
    I am looking for the information on the electron binding energy for the multi-electron atoms. Well, it is easy to find ionization energy, i. e. the binding energy of the last electron in the atom. But I need the energy which is necessary to separate all atomic electrons from the nucleus.

    Could anybody give me a reference or internet link on the subject? The information on the exited atomic states would be also useful (i.e. the binding energy of the first excited state for the Li3 atom).

    Thank you very much!
  2. jcsd
  3. Jan 17, 2006 #2
  4. Jan 17, 2006 #3
    Dear inha,

    Thank you very much for your reply and for the reference to XDB. But as far as I understand, this booklet provides binding energies relative to the vacuum level for the rare gases, relative to the Fermi level for the metals, and relative to the top of the valence bands for semiconductors.

    Well, but I would prefer to find the binding energy relative to the state of fully ionised nucleus :confused:. I am not sure if this information exists in the Web or elsewere. Probably, I've got something wrong...
  5. Jan 17, 2006 #4
    One can do total-energy calculations of atoms and molecules (Density Functional Theory). From the differences, one can compute ionization energies and excitation energies.
  6. Jan 28, 2006 #5
    I use the tables in The Elements by John Emsley.
    But I hit the problem of not being able to determine which isotope of each element is used as the standard isotope for the data given on each element. The relative atomic mass given with the heading (for each element) cannot always be matched with one of the atomic mass numbers given for each isotope.
    You will have the same problem matching the Binding energies to a particular isotope.
    The energy required to remove the outer ten electrons is listed in one table and the energy required to remove an electron from each shell and sub-shell is listed separately in different units, a conversion factor is given in the intro.
    Emsley gives the imformation source, but I find the books and papers referred to, are not available on loan from the British Library (London reference section only) and are general to expensive to purchase even when available. To put it bluntly in the UK one has to be either an academic at a top quality university, live in London, or be moderately wealthy; in order to have reasonable access to the sort of material needed for basic research.
    Lately, I have noticed that even academics are now (writing to the press) complaining about the difficulty of getting imformation at an affordable price. The internet has allowed publishers to become large scale sellers of copyright imformation at prices far in excess of what they were in pre-internet days.
    If you find a good source please let me know.
    Last edited: Jan 28, 2006
  7. Jan 28, 2006 #6


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  8. Jan 29, 2006 #7

    Thanks for your reply. Rules do not allow me to go into details of my project (no complaint about that). What I need is the atomic radius for each isotope and ion. So far I have only found two (rarely three) radii for isotopes of about half of the elements, none for different ions; and that is insufficient for my needs.
    I also note that most of the imformation comes from 'chemistry' books and forums which leads me to ask am I on the wrong forum?
  9. Jan 29, 2006 #8


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    Atomic radii for all elements can be got from Webelements. Ionic radii for the most common oxidation states can be looked up in the Shannon-Prewitt tables. Finding all the radii (from unionized to completely ionized) will be hard. It's possible that NIST has such data, which I'd guess, is more likely theoretical (or at best semi-empirical) calculations than experimental data.

    It's between here and there. Chemists are not interested in anything beyond the first few ionization (maybe just past the natural oxidation state) energies. And they are rarely interested in the ionic radii of free ions (like in a plasma).
  10. Jan 30, 2006 #9

    Emsley gives the atomic radii for most elements. There is considerable difference between Emsley and the figures given on some (university) websites; but I find Emsley to be the one that produces usable results.

    Discovered NIST after sending last reply, there is a formula in one paper that I hope to read today. (only 'hobby' time can be spent on project).

    The note on chemists clarifies that point at last.

    Will check out Shannon-Prewitt tables.

    Altogether a most helpful reply, many thanks,

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