A Unique LnIII {[3.3.1]GaIII Metallacryptate} Series That Possesses Properties of Slow Magnetic Relaxation and Visible/Near-Infrared Luminescence.

A new family of [3.3.1] metallacryptates with the general composition [LnGa6 (H2 shi)(Hshi)(shi)7 (C5 H5 N)] (Ln-1; shi3- =salicylhydroximate; Ln = Pr, Nd, Sm-Yb) has been synthesized and characterized. Ln-1 display both interesting magnetic and luminescent properties. Sm-1 has sharp emission bands in the visible and the near-infrared (NIR) regions with quantum yield values (QSmL ) of 1.64(9) and 5.5(2). 10-2  %, respectively. Tb-1 exhibits a weak green emission (QTbL =1.89(3). 10-1  %) while Pr-1, Nd-1, Ho-1, Er-1, and Yb-1 possess emission bands in the NIR range with QPrL =3.7(2). 10-3  %, QNdL =1.71(5). 10-1  %, QHoL =1.1(2). 10-3  %, QErL =7.1(2). 10-3  % and QYbL =0.65(3) %. Nd-1, Dy-1, and Yb-1 display slow magnetization relaxation in an applied field, where only Dy-1 has been observed to follow an Orbach process (Ueff =12.7 K). The combination of NIR emission with magnetic properties makes Nd-1 and Yb-1 attractive candidates as smart materials addressable in two manners.