![]() | It is amazing, that in the 2D Ising model transition between these two phases is remarkably sharp, since M approches zero at critical temperature Tc = 2.2692... with infinite slope. This phenomenon is called the second order phase transition. In this transition order parameter M is continuous but susceptibility χ and specific heat C, which are expressed as the second derivatives of the partition function Z, diverge at Tc . Order parameter is expressed as the first derivative of Z and it is discontinuos at the critical temperature in the first order phase transition. |
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