Magnetic Properties of a Single‐Molecule Lanthanide–Transition‐Metal Compound Containing 52 Gadolinium and 56 Nickel Atoms

Abstract

Monodisperse metal clusters provide a unique platform for investigating magnetic exchange within molecular magnets. Herein, the core-shell structure of the monodisperse molecule magnet of [Gd52 Ni56 (IDA)48 (OH)154 (H2 O)38 ]@SiO2 (1 a@SiO2 ) was prepared by encapsulating one high-nuclearity lanthanide-transition-metal compound of [Gd52 Ni56 (IDA)48 (OH)154 (H2 O)38 ]⋅(NO3 )18 ⋅164 H2 O (1) (IDA=iminodiacetate) into one silica nanosphere through a facile one-pot microemulsion method. 1 a@SiO2 was characterized using transmission electron microscopy, N2 adsorption-desorption isotherms, and inductively coupled plasma-atomic emission spectrometry. Magnetic investigation of 1 and 1 a revealed J1 =0.25 cm(-1) , J2 =-0.060 cm(-1) , J3 =-0.22 cm(-1) , J4 =-8.63 cm(-1) , g=1.95, and z J=-2.0×10(-3) cm(-1) for 1, and J1 =0.26 cm(-1) , J2 =-0.065 cm(-1) , J3 =-0.23 cm(-1) , J4 =-8.40 cm(-1) g=1.99, and z J=0.000 cm(-1) for 1 a@SiO2 . The z J=0 in 1 a@SiO2 suggests that weak antiferromagnetic coupling between the compounds is shielded by silica nanospheres.

Topological insights in polynuclear Ni/Na coordination clusters derived from a schiff base ligand

“…The aim to use Na 2-CO 3 as the base to introduce carbonate bridges to the system results in the presence of one Na I in both CCs, while both compounds have different structures to the previously reported homometallic Ni II CC with H 2 L1 [69]. In 1, the use of Na 2 CO 3 did not result in the introduction of carbonate bridging groups; however, in 2, where the reaction solution was exposed to a high CO 2 atmosphere during slow evaporation, a single CO 3 2-anion is observed. 1 and 2 are new additions to a large family of previously reported Ni II /Na I CCs.…”

“…The Na I ion coordinates to the (OO) pocket between the methoxide and phenoxido atoms of three ligands with the seventh position fulfilled by a H 2 O molecule. The CO 3 2-entity bridges Ni2, Ni4, Ni5 and Ni6 through a (l 5 -CO 3 ) ion. Na-O bond distances range from 2.282 to 2.625A.…”

“…These entities are of great interest for their aesthetically beautiful structures [2][3][4], unexpected transformations [5][6][7] and potential applications in magnetism [8][9][10], luminescence [11][12][13][14][15], catalysis [16][17][18], etc. Paramagnetic transition metal CCs are of intense interest and have attracted a vast amount of attention since the discovery that some CCs behave as single-molecule magnets (SMMs) [19][20][21].…”

“…Ni(II) CCs with bridging carbonate ligands are known, structural factors and magnetic exchange within these clusters greatly vary due to the large number of coordination modes of the CO 3 2-anion [39,49,50]. Some interesting examples include, a Ni 6 containing a carbonato bridge [51] and an Ni 12 where four Ni 4 O 4 units are templated around a central CO 3 2-anion core [52].…”

“…Some interesting examples include, a Ni 6 containing a carbonato bridge [51] and an Ni 12 where four Ni 4 O 4 units are templated around a central CO 3 2-anion core [52]. On the other hand, the first reported mixed Ni II /Na II CC was reported in 1976 by Jonas for potential small-molecule activation [53].…”