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Welcome to the website for Pathria, Beale: Statistical Mechanics, 3rd Edition.
Statistical Mechanics
This site consists of Mathematica Files, and Errata.
Mathematica Files
Exact calculation of the partition function of the two-dimensional Ising model on an n × m square lattice.
This Mathematica code calculates the exact partition function of the two-dimensional Ising model on an n × m square lattice with periodic boundary conditions. Copyright : Paul D.Beale,2010.
The code is based on:
Paul D. Beale, Phys. Rev. Lett. 76, 78 (1996), |
The user's input parameters are two positive integers n and m specifying the numbers of rows and columns of the square lattice. The code has been tested on lattice sizes up to 128 × 128.
The code calculates:
z = Sum[g[[q + 1]] x^(2 q), {q, 0, n m}] = partition function defined in energy 4qJ above the ground state. x = Exp[-2 K] is the Boltzmann factor for a single spin flip where K=J/kT s[[q + 1]]=Log[g[[q+1]]]= microcanonical entropy for energy 4qJ above the ground state. |
This code may be used for noncommercial purposes by referencing:
Paul D. Beale, Phys. Rev. Lett. 76, 78 (1996), |
Input n and m:
n is the number of rows and m is the number of columns. |
Errata - Updated July 2012
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