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Born oppenheimer approximation vs adiabatic approximation

  1. Sep 20, 2011 #1
    I'm learning to deal with h2+ (hydrogen ion) problems and the like, which sure entails the infamous born oppenheimer approximation .
    i know the word "adiabatic" in a thermal sense, that is , an adiabatic process is the one in which no heat transfer occurs between the things of question and surroundings.
    but , I don't quite understand that in quantum mechanics ,how the notion of "adiabatic" enters the story, say, in particular born oppenheimer approximation and adiabatic approximation is synonym .
    it's said that the notion of adiabatic has a lots of applications in many branches of physics, would anyone please but tell me some of them?

    many thanks in advance :D
  2. jcsd
  3. Sep 20, 2011 #2


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  4. Sep 20, 2011 #3


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    Adiabatic in thermodynamics has a different meaning than in molecular quantum mechanics.
    In greek it signifies "no passage" or "no trespassing", however who or what is not passing is different in different contexts:
    On a greek airport, it is persons, in thermodynamic it is heat and in molecular physics it is no passing from one potential energy surface (electronic state) to the other.
  5. Sep 24, 2011 #4
    many thanks first! I gotta apologize for delayed reply .
    Actually I'd took a glance at the wiki's explanation contained in the first link before I put up
    this question here. I usually distrust wiki. However, The second link is quite helpful. I'm reading it now while typing message to you . Seems like even serious science stuffs in wiki can be trusted sometimes.
    regards :D
  6. Sep 25, 2011 #5
    THanks very much for your reply. I think your interpretation of adiabatic hit the spot. I guess adiabatic ,roughly speaking , pretty much has to do with an isolation from the environment in a certain form. but it still remains to us the question why in particular born oppenheimer approximation is another name for adiabatic approximation in quantum mechanical sense .
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