Synthesis and magnetochemistry of heterometallic triangular Fe III2LnIII (Ln = La, Gd, Tb, Dy, and Ho) and Fe III2YIII complexes

Abstract

A series of Fe₂Ln (Ln = La, Gd, Tb, Dy and Ho) and Fe₂Y complexes have been synthesized via metal substitution and characterized by single crystal X-ray diffraction. All the molecules are isostructural and have a Fe₂LnO triangular core with the oxygen atom existing as an μ₃-oxo²⁻ anion. DC and AC magnetic susceptibility studies were performed on all the molecules. For Fe₂Ln (Ln = Gd, La) and Fe₂Y, the data were fitted to Van Vleck equations and the magnetic coupling constants were obtained. In all cases, the two Fe(III) spins were found to be antiparallel to each other in the ground state leaving the heterometal to remain essentially uncoupled.