Effect on the geometry over the slow relaxation o the magnetization in a series of erbium(III) complexes based on halogenated ligands

We report the synthesis, crystal structures, and magnetic and theoretical investigations of five erbium complexes based on halogenated ligands with the respective formulas trans-[Er(L-1)(3)(THF)(2)] (1), transl-Er(L-2)(3)(Ph3PO)(2)] (2), fac-[Er(L-3)(3)(THF)(3)](3), fac-[Er(L-4)(3)(Ph3PO)(3)] (4), and [Er(L-5)(3)] (5) (L-1 = OCPh2(CF2Cl), L-2 = OCPh(CF3)(2) , L-3 = OCH(C6F5)(2), L-4 = OCHMe(C6F5), L-5 = 1,8-dibromo-3,6-di-tert-butylcarbazol-9-ide, THE = tetrahydrofuran). Modulation of the experimental conditions allows controlling the coordination geometry of the resulting complexes. While 1 and 2 adopt a trigonal bipyramidal geometry, 3 and 4 exhibit a distorted octahedral arrangement. In contrast 5 exhibits a triangular coordination geometry. Magnetic investigations in line with theoretical calculations reveal that only the three-coordinated complex 5 exhibits a zero-field slow relaxation of the magnetization, while compound 1 demonstrates field-induced relaxation dynamics.

Automated summary

This study reports the synthesis, crystal structures, magnetic properties, and theoretical investigations of five erbium complexes. The coordination geometry of the complexes can be controlled by adjusting experimental conditions, with each complex exhibiting different magnetic behaviors and coordination structures.