Local variations of the magnetization effected by an external field in molecular rings

It is shown that an external magnetic field generates local variations of the classical ground-state magnetization in molecular rings of antiferromagnetic icosahedra with isotropic spin interactions. The magnetic response is characterized by a multitude of magnetization and susceptibility discontinuities occurring across the ring. In addition, a parity effect with respect to the evenness or oddness of the number of icosahedra allows for magnetization jumps that occur at different field values for different molecules and produce an even more pronounced local variation of the magnetization. It is also found that for specific field ranges all canting angles of the molecular magnetizations increase with the field. These findings are in sharp contrast with the ones for rings of individual spins.