Nonanuclear lanthanide(Ⅲ) nanoclusters: Structure, luminescence and magnetic properties

摘要

A series of nonanuclear lanthanide(Ⅲ) nanoclusters, (CH_3)_3NH[Ln9(L)_(16)(μ_3-OH)_8(μ5-O)_2](CH_3OH) where Ln = Nd, Eu, Tb, Gd, Dy, Er, Yb and HL = (2-hydroxy-5-methylphenyl)propan-1-one, was successfully synthesized and characterized by photoluminescence, magnetic susceptibility and X-ray crystallography. (CH_3)_3NH[Gd_9(L)_(16)(μ_3-OH)_8(μ_5-O)_2](CH_3OH) crystallized in the monoclinic space group C2/c, with a monovalent anionic cluster and a tertiary ammonium counter ion. Temperature dependent photoluminescence studies of ((CH_3)_3NH)_(0.5)[Eu_9(L)_(16)(μ_3-OH)_8(μ_5-O)_2](H_2O)_5 highlights the presence of two distinct metal centers and temperature dependent magnetic susceptibilities for both ((CH_3)_3NH)_(0.5)[Dy_9(L)_(16)(μ_3-OH)_8(μ5-O)_2](H_2O)_4 and ((CH_3)_3NH)_(0.5)[Tb_9(L)_(16)(μ_3-OH)_8(μ_5-O)_2](H_2O)_5 suggest weak antiferromagnetic interactions between the lanthanide(Ⅲ) ions.