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Does anyone know the ionic radius of hydride(anion of hydrogen)?

  1. Dec 2, 2009 #1
    I come from Hong Kong and want to know the ans. THX very much!

    Also curious to know, which nationality will browse this forum most?
  2. jcsd
  3. Dec 2, 2009 #2
    In which compound? As I'm sure you aware, you cannot really get get hydride by itself, so the issue may be where the hydride stops and the counter ion starts.
  4. Dec 2, 2009 #3
    In water the internuclear distance from the hydrogen ion to the oxygen atom is .965 angstroms. in Hydrogen sulfide it is 1.34 angstroms to the sulfur. In H2Se it is 1.47 and in H2Te it is 1.67.
  5. Dec 2, 2009 #4


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    These are not hydride (H-).
  6. Dec 3, 2009 #5


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    The radius of hydride is practically identical to hydrogen. The second electron is in the same orbital.

    The very slight change in radius due to the electron-electron interactions isn't going to be important. Ionic radii are a crude measure in any case.
  7. Jun 30, 2010 #6
    A quick analysis of the alkali metal hydride crystal structures (and using the Shannon-Prewitt ionic radii for the metals) gives an average 1.3 angstrom (130 pm) radius for H-. Roughly about the same size as an oxide ion.
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