We present calculations of the complex-temperature zeros of the partition functions for 2D Ising models on the square lattice with spin $s=1$ , 3/2, and 2. These give insight into complex-temperature phase diagrams of these models in the thermodynamic limit. Support is adduced for a conjecture that all divergences of the magnetisation occur at endpoints of arcs of zeros protruding into the FM phase. We conjecture that there are $4[s^2]-2$ such arcs for $s \ge 1$ , where $[x]$ denotes the integral part of $x$ .We present calculations of the complex-temperature zeros of the partition functions for 2D Ising models on the square lattice with spin $s=1$, 3/2, and 2. These give insight into complex-temperature phase diagrams of these models in the thermodynamic limit. Support is adduced for a conjecture that all divergences of the magnetisation occur at endpoints of arcs of zeros protruding into the FM phase. We conjecture that there are $4[s^2]-2$ such arcs for $s \ge 1$, where $[x]$ denotes the integral part of $x$.

arXiv:hep-lat/9505005Journal of Physics A Mathematical and GeneralNov 7, 199527 citations

We present calculations of the complex-temperature zeros of the partition functions for 2D Ising models on the square lattice with spin

s=1

, 3/2, and 2. These give insight into complex-temperature phase diagrams of these models in the thermodynamic limit. Support is adduced for a conjecture that all divergences of the magnetisation occur at endpoints of arcs of zeros protruding into the FM phase. We conjecture that there are

4[s^2]-2

such arcs for

s \ge 1

, where

[x]

denotes the integral part of

x