The zeros distribution of Z_5-symmetric model on a triangular lattice




Statistical Mechanics, Triangular Lattice, Zeros Distribution


We study the -symmetric model with the nearest neighbour interaction between molecular dipole of five spin directions i.e. Q=5 which called as the -symmetric model on a triangular lattice. We investigate the zeros of partition function and the relationship to the phase transition. Initially, the model is defined on a triangular lattice graph with the nearest neighbour interaction. The partition function is then computed using a transfer matrix approach. We analyse the system by computing the zeros of the polynomial partition function using the Newton-Raphson method and then plot the zeros in a complex plane. For this lattice, the result shows that for specific type of energy level there are multiple line curves approaching real axis in the complex plane. The equation of the specific heat is produced and then plotted for comparison. Motivated from the work by Martin (1991) on models on square lattice, we extend the previous study to different lattice type that is triangular lattice.

Author Biographies

Siti Fatimah Zakaria, International Islamic University Malaysia

Computational and Theoretical Sciences Department, Kulliyyah of Sciences

Nor Sakinah Mohd Manshur, International Islamic University Malaysia

Computational and Theoretical Sciences Department, Kulliyyah of Sciences


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