Structural analysis and electronic properties of a homodinuclear erbium(III) complex bridged by the polyazine ligand 2,2′-bipyrimidine

The Utility of 2,2′-Bipyrimidine in Lanthanide Chemistry: From Materials Synthesis to Structural and Physical Properties

“…The complex readily precipitates from the reaction mixture. In most cases, homodinuclear complexes of general formula [{Ln(β) 3 (X) n (solv) m } 2 (μ-bpm)] (Ln = Nd, Eu, Gd, Tb, Ho, Er, Yb, Lu; X = NO 3 − , Cl − ; n = 0, 3; m = 0, 1) were obtained after recrystallization [67,[70][71][72][73][74][75][76][77][78]. The structure of the complex [{Nd(dbm) 3 (THF)} 2 (μ-bpm)] is shown at the top of Figure 2 as a representative example.…”

“…It is only recently that chemists have started to investigate the ability of 2,2 -bipyrimidine to form complexes with the lanthanide ions. Luminescence studies have been performed on mixed d-f complexes [62][63][64][65][66], monometallic [67][68][69] and homo-bi-and polymetallic complexes [67,[70][71][72][73][74][75][76][77][78][79][80]. In particular, bpm was shown to connect a transition metal and a lanthanide ion, allowing sensitization of the lanthanide luminescence by the transition metal [62,81].…”

Structure, luminescence and magnetic properties of an erbium(iii) β-diketonate homodinuclear complex

“…Different strategies can be distinguished in terms of the bridging approach: the two Er 3+ ions may be bridged through the b-diketonate, 31 through solvent molecules [32][33][34] or through a moiety specifically designed for this task. In the latter case, there are examples with 2,2 0 -bipyrimidine ([Er 2 (tfa) 6 (m-bpm)], 35,36 which showed very weak antiferromagnetic coupling; [Er 2 (hth) 6 (m-bpm)]; 37 [Er 2 (acac) 3 (m-bpm)] 38 and [Er 2 (fod) 6 (m-bpm)] 39 ) and with 4,4 0 ,7,7 0 -tetra-tert-butyl-2,2 0 -bi-1,3-benzodithiole-5,5 0 ,6,6 0 -tetrone. 40 In an attempt to attain single-ion-magnet behavior, 3d-4f b-diketonate-based heterodimetallic complexes, such as [(Er(hfac) 3 ) 2 (Ni(dpk) 2 (phen))] and [(Er(hfac) 3 ) 2 (Ni(dpk) 2 (py) 2 )], 41 the oxime-based [Er 3 Cu 8 (HL) 6 (m 4 -O) 2 Cl 6 (H 2 O) 8 ]Cl 3 42 and [(L 1 )-MEr(hfac) 3 ] (M = Cu II , Ni II ; L 1 = 4,5-bis(propylthio)tetrathiafulvalene-N,N 0 -phenylenebis(salicylideneimine)), 43 have also been tested, but without success.…”