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Terminology Question: non-Arrhenius

  1. Feb 22, 2013 #1
    A temperature activated phenomenon/process, K, is said to be Arrhenius if dlog(K)/d(1/T) is constant where T is the absolute temperature.

    Now suppose a process exhibits two constant slopes (m1,m2) when plotted versus (1/T), say m1 governs the low T behavior and m2 governs the high T behavior. Can one call this a non-Arrhenius process. Or is it necessary for the curvature of the plot to have a nonzero value in order for this process to be called non-Arrhenius.

    (I actually posted this before in the Chemistry forum but got no response, so I thought may be I can get some hint here, after all this topic is interdisciplinary)
     
  2. jcsd
  3. Feb 22, 2013 #2

    DrDu

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    Well, I don't think the term "non-Arrhenius" is very strictly defined.
    Somewhere in the intermediate temperature region, the curve will nave a non-vanishing curvature if the slope is different at low and high temperatures, so you may call it non-Arrhenius.
    On the other hand, an Arrhenius type behaviour will always only be observed in some restricted temperature region which you should specify. As you seem to want to discuss both regimes simultaneously I think it is justified to speak of a non-Arrhenius behaviour.
     
  4. Feb 22, 2013 #3
    Thank you for sharing your thoughts! I think now I tend to believe that the case I described is better termed as non-Arrhenius.
     
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