Tracking the Stepwise Formation of the Dysprosium Cluster (Dy10) with Multiple Relaxation Behavior

Abstract

High-nuclear lanthanide clusters are generally formed by the rapid accumulation of simple building units. Thus, tracking and observing the stepwise assembly process, which is vital for understanding the assembly mechanism, are extremely difficult. Herein, the decanuclear nanocluster [Dy 10 (L 1 ) 6 (μ 5 -NO 3 ) 2 (OAc) 10 (HOAc, and 3-amino-1,2-propanediol (L 3 ). The reaction process was further tracked by time-dependent high-resolution electrospray ionization mass spectrometry, and seven reaction intermediate fragments were screened. A stepwise assembly mechanism was observed based on these fragments, that is, L → Dy1 → Dy2 → Dy3 → Dy4 → Dy5 → Dy6 → Dy10. This study is the first to discover a stepwise assembly mechanism during the formation of high-nuclear lanthanide clusters (cluster nucleus > 3). Magnetic studies have shown the multiple relaxation behavior of Dy10.

Assembly of Dy60 and Dy30 cage-shaped nanoclusters

“…In the design and synthesis of high-nuclearity lanthanide clusters, multidentate chelating ligands can rapidly bind and stabilize Ln(III) ions, making their self-assembly regular [15][16][17][18][19] . The selection of suitable multidentate chelating ligands is instrumental for studies on the assembly mechanism of high-nuclearity lanthanide clusters 20,21 . The acylhydrazone ligands with strong chelating ability, multiple coordination modes, and easily changing coordination configurations have made progress in the synthesis of low-nuclear lanthanide clusters [15][16][17] ; however, their use in the design and synthesis of giant lanthanide clusters is rare 18,19 .…”

“…In the hydrothermal/solvothermal "black box" system under certain temperature and pressure conditions, the temperature and pressure in a closed system make the collision between reaction species confusing. Thus, the exploration of the assembly mechanism of coordination molecular clusters is slow [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] . Although complex, progress has been made in polyoxometalates [22][23][24][25]36,37 , coordination supramolecular systems 38,39 , coordination molecular cages 26,[40][41][42][43][44][45] , 3d metal-ion clusters [30][31][32][33] , and so on 46,47 .…”

“…Although complex, progress has been made in polyoxometalates [22][23][24][25]36,37 , coordination supramolecular systems 38,39 , coordination molecular cages 26,[40][41][42][43][44][45] , 3d metal-ion clusters [30][31][32][33] , and so on 46,47 . Highvalence Ln(III) ions usually have complex coordination configurations, rich and diverse coordination modes, and coordination balls that are prone to distortion 20,21,[48][49][50] . Such drawbacks lead to the formation of several types of assembly methods in the synthesis of high-nuclearity lanthanide clusters, such as multitemplate induction and stepwise assembly 20,21,[48][49][50] .…”

“…Highvalence Ln(III) ions usually have complex coordination configurations, rich and diverse coordination modes, and coordination balls that are prone to distortion 20,21,[48][49][50] . Such drawbacks lead to the formation of several types of assembly methods in the synthesis of high-nuclearity lanthanide clusters, such as multitemplate induction and stepwise assembly 20,21,[48][49][50] . Given that various assembly methods exist, the formation process of highnuclearity lanthanide clusters is confusing and exploring the assembly mechanism is difficult 20,21,[48][49][50] .…”

“…Such drawbacks lead to the formation of several types of assembly methods in the synthesis of high-nuclearity lanthanide clusters, such as multitemplate induction and stepwise assembly 20,21,[48][49][50] . Given that various assembly methods exist, the formation process of highnuclearity lanthanide clusters is confusing and exploring the assembly mechanism is difficult 20,21,[48][49][50] . Therefore, studies on the assembly mechanism of lanthanide clusters are limited 20,21,[48][49][50][51] .…”