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Homework Help: How to convert cm^-1 into erg or joules

  1. Feb 5, 2010 #1
    I'm not sure if this is the right place for this, but I can't seem to find how to convert cm^-1 into erg or joules... It's a pretty dumb question, but I can't find the answer anywhere.

    Thanks a lot in advance!
     
  2. jcsd
  3. Feb 5, 2010 #2

    uart

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    Re: Energy?

    You cant, because cm^(-1) is not a unit of energy. The base units of energy are m l t^(-2). For example Ergs are grams cm seconds^(-2) and Joules are kg m seconds^(-2).
     
  4. Feb 5, 2010 #3

    uart

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    Re: Energy?

    The only meaning that I can think of for that is perhaps comparing the energy to that of a photon of wavelength one cm.

    For example, a photon of wavelength 1mm would have an energy of 10 cm^(-1) and so on.

    In that case the conversion factor would just be the energy of a photon wavelength 1cm, which is 100 h c, or about 1.99 x 10^(-23) Joules.

    In what context did you see this unit used Alien?
     
  5. Feb 5, 2010 #4
    Re: Energy?

    Failed to mention context, sorry. But yes, it was the way you predicted. Thank you very much!

    It was a Chemistry problem about crystal fields.
     
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