The partition function zeros of the antiferromagnetic spin-12 Ising–Heisenberg model on a diamond chain are studied using the transfer matrix method. Analytical equations for the distributions of Yang–Lee and Fisher zeros are derived. The Yang–Lee zeros are located on an arc of the unit...

The introduction of a metric onto the space of parameters in models in statistical mechanics and beyond gives an alternative perspective on their phase structure. In such a geometrisation, the scalar curvature, R, plays a central role. A non-interacting model has a flat geometry (R=0), while R...