I'm stuck on a question about deriving an expression for the magnetic susceptibility in terms of the variance of the magnetisation for a simple 2d square ising model.(adsbygoogle = window.adsbygoogle || []).push({});

I get the derivation of the specific heat, and I know am supposed to do something similar to get to the expression for susceptibility d<M>/dH. But how? Any help would be much appreciated.

[beta is 1/KT]

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# Homework Help: Simple ising model: Magnetic susceptibility derivation

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