$\Delta$S$^z$=2 quantum magnetization discontinuities proportional in number to the spin s in C$_{60}$: Origin and the role of symmetry

Abstract

The quantum antiferromagnetic Heisenberg model on the fullerene C_{60}60 in a magnetic field has 4s4s ground-state magnetization discontinuities with \Delta S^z=2ΔSz=2 as a function of the spin quantum number ss that disappear at the classical limit. The molecule can be seen as the fullerene C_{20}20 with interpentagon interactions that generate the discontinuities when sufficiently strong. The discontinuities originate from the antiferromagnetic Ising limit for both molecules. The results show how spatial symmetry dictates the magnetic response of the I_hIh fullerene molecules.