Magnetism Studies of Bis(acyl)phosphide-Supported Eu 3+ and Eu 2+ Complexes.

A series of bis(acyl)phosphide-supported Eu complexes were synthesized (bis(acyl)phosphide = BAP). In this study, BAP ligands proved to be excellent ligands for the synthesis of both Eu 3+ and Eu 2+ molecular complexes. Sodium bis(mesitoyl)phosphide ( Na( mes BAP) ) and sodium bis(2,4,6-triisopropylbenzoyl)phosphide ( Na( tripp BAP) ) were employed as ligand precursors for the synthesis of the Eu 3+ complexes Eu(bis(mesitoyl)phosphide) 3 (thf) 2 ( Eu( mes BAP) 3 (thf) 2 ) and Eu(bis(2,4,6-triisopropylbenzoyl)phosphide) 3 ( Eu( tripp BAP) 3 ), as well as the Eu 2+ complex, Eu(bis(2,4,6-triisopropylbenzoyl)phosphide) 2 (dme) 2 ( Eu( tripp BAP) 2 (dme) 2 ) (thf = tetrahydrofuran, dme = 1,2-dimethoxyethane). All complexes were characterized using a combination of UV-vis-NIR-IR and NMR spectroscopies, and single-crystal X-ray diffraction (SC-XRD). The magnetic properties of these three monomeric Eu complexes were investigated by variable-temperature magnetic susceptibility. The magnetic data are typical for these ions, with Eu( tripp BAP) 2 (dme) 2 displaying Curie-type behavior. Both Eu( tripp BAP) 3 and Eu( mes BAP) 3 (thf) 2 possess similar 7 F 0 - 7 F 1 spin-orbit energy gaps and a similar zero-field splitting of the 7 F 1 state.