Family of Nanoclusters, Ln 33 (Ln = Sm/Eu) and Gd 32 , Exhibiting Magnetocaloric Effects and Fluorescence Sensing for MnO 4 .

A family of nanoclusters, [Ln 33 (EDTA) 12 (OAc) 2 (CO 3 ) 4 (μ 3 -OH) 36 (μ 5 -OH) 4 (H 2 O) 38 ]·OAc· x H 2 O ( x ≈ 50, Ln = Sm for 1 ; x ≈ 70, Ln = Eu for 2 ) and [Gd 32 (EDTA) 12 (OAc) 2 (C 2 O 4 )(CO 3 ) 2 (μ 3 -OH) 36 (μ 5 -OH) 4 (H 2 O) 36 ]· x (H 2 O) ( x ≈ 70 for 3 ; H 4 EDTA = ethylene diamine tetraacetic acid), was prepared through the assembly of repeating subunits under the action of an anion template. The analysis of the structures showed that compounds 1 and 2 containing 33 Ln 3+ ions were isostructural, which were constructed by three kinds of subunits in the presence of CO 3 2- as an anion template, while compound 3 had a slightly different structure. Compound 3 containing 32 Gd 3+ ions was formed by three types of subunits in the presence of CO 3 2- and C 2 O 4 2- as a mixed anion template. The CO 3 2- anions came from the slow fixation of CO 2 in the air. Meanwhile, one kind of high-nuclearity lanthanide clusters showed high chemical stability. The quantum Monte Carlo (QMC) calculation suggested that weak antiferromagnetic interactions were dominant between Gd 3+ ions in 3 . Magnetocaloric studies showed that compound 3 had a large entropy change of 43.0 J kg -1 K -1 at 2 K and 7 T. Surprisingly, compound 2 showed excellent recognition and detection effects for permanganate in aqueous solvents based on the fluorescence quenching phenomenon.