A luminescent single-molecule magnet of dimetallofullerene with cage-dependent properties.

It is important to explore luminescent single-molecule magnets (SMMs) to promote their application in high-density data storage. Herein, we report two dimetallofullerenes of DyEr@C82 isomers, which exhibit cage-dependent single-molecule magnet behavior and photoluminescence properties. DyEr@C82 isomers were characterized with a Cs and C3v cage symmetry by UV-vis-NIR spectroscopy and single-crystal X-ray diffraction analysis. Magnetic results revealed that DyEr@C3v-C82 displays SMM behavior below 3 K, whereas DyEr@Cs-C82 is a paramagnet. In addition, photoluminescence (PL) was also observed for both of these two isomers, whose peak patterns are different. Theoretical calculations revealed the presence of a one-electron-two-center Dy-Er bond in these two isomers, and different electronic structures of DyEr@Cs-C82 and DyEr@C3v-C82, which agrees well with the experimental results. These results show that dimetallofullerenes are promising magneto-luminescent materials with varied properties.