Magnetic Properties of a Single-Molecule Lanthanide-Transition-Metal Compound Containing 52 Gadolinium and 56 Nickel Atoms

Monodisperse metal clusters provide a unique platform for investigating magnetic exchange within molecular magnets. Herein, the core-shell structure of the monodisperse molecule magnet of [Gd52Ni56(IDA)(48)(OH)(154)(H2O)(38)]@SiO2 (1a@SiO2) was prepared by encapsulating one high-nuclearity lanthanide-transition-metal compound of [Gd52Ni56(IDA)(48)(OH)(154)(H2O)(38)](NO3)(18)164H(2)O (1) (IDA=iminodiacetate) into one silica nanosphere through a facile one-pot microemulsion method. 1a@SiO2 was characterized using transmission electron microscopy, N-2 adsorption-desorption isotherms, and inductively coupled plasma-atomic emission spectrometry. Magnetic investigation of 1 and 1a revealed J(1)=0.25cm(-1), J(2)=-0.060cm(-1), J(3)=-0.22cm(-1), J(4)=-8.63cm(-1), g=1.95, and zJ=-2.0x10(-3)cm(-1) for 1, and J(1)=0.26cm(-1), J(2)=-0.065cm(-1), J(3)=-0.23cm(-1), J(4)=-8.40cm(-1)g=1.99, and zJ=0.000cm(-1) for 1a@SiO2. The zJ=0 in 1a@SiO2 suggests that weak antiferromagnetic coupling between the compounds is shielded by silica nanospheres.