Revision question 6.13

Posted by MRH on May 3, 2014, 3:58 pm

Using mean field theory, I found (no modulus) = - tanh ( gubbins *) This gives =0 at every site always. This is consistent with the fact that Cu and Zn are in equal nos (though I am not sure that I have assumed that). However the sheet asks us to find < mod(sigma)> = tanh (gubbins * Given that sigma always equals -1 or 1 at every site, mod(sigma) will always equal 1, so this solution must be incorrect. Moreover, if my equation read (no modulus) = tanh ( gubbins *) I should be very worried, since this would imply that at some temperature I could have at a site non-zero. All sites would have the same . This would imply that we no longer had equal nos of Zn and Cu, which is disallowed (though, I am not sure how the assumption was used, if at all). What is going on?

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Message Thread Revision question 6.13 - MRH May 3, 2014, 3:58 pm Re: Revision question 6.13 - Steve Simon May 4, 2014, 11:51 am Re: Revision question 6.13 - Steve Simon May 3, 2014, 4:02 pm Re: Revision question 6.13 - MRH May 3, 2014, 7:12 pm Re: Revision question 6.13 - Steve Simon May 4, 2014, 10:53 am Re: Revision question 6.13 - Steve Simon May 4, 2014, 10:43 am Re: Revision question 6.13 - Steve Simon May 4, 2014, 11:07 am « Back to index

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