Volume collapse in LaMnO 3 studied using an anisotropic Potts model

We have investigated the volume collapse occurring in ${\text{LaMnO}}_3$ unit cell using the anisotropic Potts mode modified by two types of anisotropic interactions which has been used to study the behavior of the orbital-ordering configurations with temperature. The bond lengths are related to the occupation of the orbits. We have shown that the collapse is due to the change of Mn-O bonds as the temperature is raised through the transition. These results are in good agreement with the recently published experimental results.