A series of bis(2-phenethyl)dithiophosphinate-based Ln(III) complexes: Synthesis, magnetic and photoluminescent properties

Abstract

A series of the bis(2-phenethyl)dithiophosphinate-based lanthanide(III) complexes, namely [Ln(phen)L3] (Ln = Sm (1), Eu (2)), Ln(phen)L2(NO3) (Ln = Sm (3), Eu (4), Tb (5)), and Et4N[LnL4] (Ln = Sm (6), Eu (7), Gd (8), Tb (9)), where L− = (PhCH2CH2)2PS2−, and phen = 1,10-phenanthroline, has been designed and synthesized. The magnetic properties of complexes 1–9 have been investigated in the temperature range of 2–300 K. The μeff(T) and 1/χ(T) dependences of complexes show paramagnetic behavior, which is determined by the Ln3+ ions. For complexes 5 and 9, significant anisotropy results in nonlinear field dependencies of magnetization at 2 K. Complexes 1–7 and 9 exhibit metal-centered luminescence in the solid state at room temperature, whereas complex 8 emits ligand-centered phosphorescence. The maximal quantum efficiency (φf = 53% at 300 K) is observed for the complex Tb(phen)L2(NO3).