Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Finite Size vs Point Size Hydrogen like Atoms

  1. Dec 24, 2015 #1
    Ok my question:
    what is the difference between the binding energies of these 2 types of atoms, conceptual wise, which one is greater?

    I am assuming based on the easy calculations of the potential energy of the finite size atom ( inside and outside)
    There is a difference between the potential energies of those 2 regions, and just because of that difference. It's easier to ionize the atom.
    Am I correct?

    Thank You
  2. jcsd
  3. Dec 24, 2015 #2

    Vanadium 50

    User Avatar
    Staff Emeritus
    Science Advisor
    Education Advisor
    2017 Award

    I don't know what you mean by "point sized atoms", since they do not exist in either theory or in nature, but the Rydberg constant is inversely proportional to the Bohr radius.
  4. Dec 25, 2015 #3


    User Avatar
    Science Advisor
    Homework Helper

    Unfortunately there is no answer to your question because the two types of atom you are considering are not present to begin with.
  5. Dec 25, 2015 #4


    User Avatar

    Staff: Mentor

    How do you distinguish "inside" versus "outside" for e.g. the ground state of hydrogen, for which the electron probability density as a function of r looks like the right-hand graph below? Do you mean "r large enough that the probability density is negligible"? (It never actually reaches zero.)


    (source: http://www.chemistry.mcmaster.ca/esam/Chapter_3/section_2.html)

    Both the potential and kinetic energies of the electron must also be described using probability distributions. Their sum is of course a fixed number: -13.6 eV for the ground state of hydrogen.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook