Partition function zeros for the two-dimensional Ising model VI

Special features of the complex temperature zeros of the partition function of the two-dimensional Ising model on completely anisotropic triangular lattices with all “odd” interactions, such as one with interaction ratios 5:3:1, are investigated. A bifurcation of one of the boundary lines at the imaginary axis occurs. An analytical explanation of this bifurcation is provided, and the algebraic reduction of the bifurcation eliminant to a symmetrical form is reported. Also, the end-points of lines of pure imaginary zeros are related to the critical point and disorder point equations.