Dy2@C79N: a new member of dimetalloazafullerenes with strong single molecular magnetism

Abstract

Enhancing the exchange interaction between magnetic ions is a long-term target in molecular magnetism. Endohedral metallofullerenes (EMFs) provide a possibility for achieving such a goal by imprisoning multiple magnetic centers inside the confined inner space of a fullerene cage. Here, we report a new member of dimetallic azafullerene Dy₂@C₇₉N via crystallographic determination for the first time. Magnetic studies indicate that the strong ferromagnetic coupling between lanthanide ions and unpaired electrons enables Dy₂@C₇₉N to be a favorable SMM with large energy barrier of U = 669 K and observable hysteresis loops below 24 K.