Orientational phase transition in solid $\mathrm C_{60}$: bifurcation approach

A simple model for the angle-dependent interaction between $\mathrm C_{60}$ molecules in the face-centered cubic lattice is proposed. The bifurcations of the solutions of the nonlinear integral equations for orientational distribution functions in the mean-field approximation are analyzed, and the orientational phase transition in solid $\mathrm C_{60}$ is described. The quantitative results for the orientational phase transition agree with the experimental data.