Static field induced magnetic relaxations in dinuclear lanthanide compounds of [phen<sub>2</sub>Ln<sub>2</sub>(HCOO)<sub>4</sub>(HCOO)<sub>2-2<italic>x</italic>(NO<sub>3</sub>)<sub>2<italic>x</italic>] (1, Ln = Gd and <italic>x</italic> = 0.52; 2, Ln = Er and <italic>x</italic> = 0.90; phen = 1,10-phenanthroline)</sub></sub>

Abstract

Two dinuclear lanthanide (Ln) complexes, formulated as [phen 2 Ln 2 (HCOO) 4 (HCOO) 2-2 x (NO 3 ) 2 x ] (1, Ln = Gd and x = 0.52; 2, Ln = Er and x = 0.90; phen = 1,10-phenanthroline), were synthesized and characterized. They are isostructural. The dinuclear molecule consists of two Ln 3+ bridged by four formate groups and chelated by phen and formate/nitrate ligands, and the Ln 3+ possesses a coordination environment of distorted tri-capped trigonal prism of LnO 7 N 2 . Both compounds behave as paramagnets between 2 and 300 K, but display two static field induced magnetic relaxation processes. One is slow and of spin-lattice type, and it results from the lifting of Kramer's degeneracy of the ground-states of both Gd 3+ and Er 3+ , and the other is fast, and it might be spin-spin type.