Research News, May 12th, 2021

Synthesis, Structure and Magnetic Properties of Rare-Earth
Bis(diazabutadiene) Diradical Complexes
 
Haihan Yan, Botao Wu, Yin-Shan Meng,* Wen-Xiong Zhang,* and Zhenfeng Xi
Inorg. Chem. 2021, 60, 1315–1319.
 
   
    A new kind of diradical rare-earth metal complexes supported by diazabutadiene (DAD) ligands [(DAD)2LnN(TMS)2] (1, Ln = Dy, Lu) were synthesized and studied. They showed a new [radical-Ln-radical] alignment with distorted square pyramidal geometry. Structural and DFT analysis illustrated the radical anionic nature of the ligands. Magnetic studies revealed the antiferromagnetic coupling of the two radicals in 1-Lu. 1-Dy showed the typical single-molecule magnet (SMM) behavior with the effective energy barrier of 231 K, which is much higher than similar radical-containing SMMs. Magneto-structural analysis suggests that the anionic [N(TMS)2]- group plays the vital role for the SMM property. This study provides a new platform for further improving the performance of radical-lanthanide SMMs.