Low coordinated mononuclear erbium(iii) single-molecule magnets with C3v symmetry: a method for altering single-molecule magnet properties by incorporating hard and soft donors.

Structures and magnetic characteristics of two three-coordinate erbium(iii) compounds with C3v geometry, tris(2,6-di-tert-butyl-p-cresolate)erbium, Er(dbpc)3 (1) and tris(bis(trimethylsilyl)methyl)erbium, Er(btmsm)3 (2), were determined. Both underwent temperature-dependent slow magnetic relaxation processes in the absence of an external magnetic field. As a result of the differences in the coordination environment, they exhibit different energy barriers and quantum tunneling of magnetization (QTM) constants.