Synthesis, Structure, Thermal Stability, and Magnetic and Luminescence Properties of Dinuclear Lanthanide(III) Pivalates with Chelating N‐Donor Ligands

Abstract

New dinuclear lanthanide pivalate complexes [Tb2(piv)6(Hpiv)6], [Tb2(piv)6(bpy)2], [Tb2(piv)6(phen)2], [Tb2(piv)6(bath)2]·1.5EtOH, and [Eu2(piv)6(bath)2]·2EtOH, as well as the coordination polymer {Tb(piv)3}n, in which piv = (CH3)3CCO2–, bpy = 2,2′‐bipyridine, phen = 1,10‐phenanthroline, bath = 4,7‐diphenyl‐1,10‐phenanthroline, and EtOH = ethanol, were synthesized and characterized by X‐ray diffraction. For the terbium complexes, the magnetic properties and the solid‐state thermolysis were investigated. The phase composition of the solid decomposition products was determined by X‐ray powder diffraction. The photophysical properties of these complexes were analyzed by luminescence, excitation, and phosphorescence spectroscopy, and by lifetime measurements. A comparison of the photophysical data for bpy, phen, and bath complexes shows that the supramolecular organization affects the efficiency of the sensitization of Ln3+ luminescence. All the results obtained provide good prospects for the use of dinuclear lanthanide pivalate complexes as efficient light‐conversion molecular devices (LCMD).

Binuclear Gadolinium(III) Pivalates with 4,7‐Diphenyl‐1,10‐Phenanthroline: Synthesis, Structure, Thermal Behavior, Magnetic and Photoluminescence Properties

“…The reaction of [Gd 2 (piv) 6 (Hpiv) 6 ] with an excess of the bath ligand in ethanol under air via a solution chemistry approach, which was used in our previous study [7] to synthesize binuclear carboxylates [Eu 2 (piv) 6 ( bath ) 2 ]⋅ x Solv, where Solv = EtOH, H 2 O, x = 0‐2, followed by variation of the crystallization conditions resulted in the sequential formation of new single‐phase pivalates [Gd 2 (piv) 6 ( bath ) 2 ]⋅2EtOH ( 1a ⋅2EtOH) and [Gd 2 (piv) 6 ( bath ) 2 ]⋅1.5EtOH⋅0.5H 2 O ( 1b ⋅1.5EtOH⋅0.5H 2 O) and the complex [Gd 2 (piv) 6 ( bath ) 2 ]⋅H 2 O ( 1c ⋅H 2 O) prepared in our previous study [8] . It should be noted that lanthanide carboxylates are generally synthesized by the hydro(solvo)thermal method or the gel technique [1a,11] .…”

“…Recently, we reported the controllable synthesis of binuclear pivalates [Eu 2 (piv) 6 ( bath ) 2 ]⋅ x Solv, where Solv = EtOH, H 2 O, x = 0‐2, which have different molecular and crystal structures [7] . In continuation of our ongoing research on the complexation of this very interesting class of carboxylate complexes, here we investigated the formation of new binuclear pivalates [Gd 2 (piv) 6 ( bath ) 2 ]⋅2EtOH ( 1a ⋅2EtOH) and [Gd 2 (piv) 6 ( bath ) 2 ]⋅1.5EtOH⋅0.5H 2 O ( 1b ⋅1.5EtOH⋅0.5H 2 O) and the previously synthesized complex [Gd 2 (piv) 6 ( bath ) 2 ]⋅H 2 O ( 1c ⋅H 2 O), [8] which were produced in the [Gd 2 (piv) 6 (Hpiv) 6 ]‐ bath (4,7‐diphenyl‐1,10‐phenanthroline) reaction system in the presence of EtOH in air, examined their thermal behavior under an inert atmosphere, and studied photoluminescence properties. We also investigated the magnetic properties and analyzed the ESR spectra of binuclear pivalates 1a ⋅2EtOH, 1b ⋅1.5EtOH⋅0.5H 2 O, 1c ⋅H 2 O, and 2 – 4 and polymeric pivalate 5 , the synthesis and structures of which were described in our recent publications [8,9] and reported in the study [10] …”

A new cost-effective polymeric film containing an Eu(III) complex acting as UV protector and down-converter for Si-based solar cells and modules

“…The thermal decomposition of [Eu 2 (phen) 2 (bz) 6 ] starts around 275 1C with a mass loss of about 20% which corresponds to the decomposition of the phenanthroline ligand [35]. It continues with the degradation of the benzoic acid and ends up with the formation of Eu 2 O 3 above 800 1C [36]. Therefore, the Eu-based PMMA layer can be placed on the glass in any step of the module assembly of crystalline silicon solar cells, as the whole standard assembly process is produced at temperatures below 200 1C.…”

Synthesis, Structure, Photoluminescence, and Electroluminescence of Four Europium Complexes: Fabrication of Pure Red Organic Light‐Emitting Diodes from Europium Complexes

“…Although the luminescence of the europium ion can be efficient, the ion suffers from weak light absorption, because the electric‐dipole f–f transitions that result in light emission from the europium ion are parity‐forbidden, in spite of the opposite‐parity‐allowed magnetic‐dipole f–f transitions . One way to overcome the problem of the weak f–f absorption transition of the europium ion and to achieve bright emission is to surround the ion with adequate organic ligands able to harvest light and to subsequently transfer the electronic energy to the metal‐ion excited states, while simultaneously providing a rigid protective coordination shell for minimizing nonradiative deactivation , , . This indirect excitation process is known as the antenna effect or sensitization .…”