Luminescence and Magnetic Properties of Tb(III) Complexes with TETA and Synergistic Effect by 1,10‐Phenanthroline

Abstract

Two Tb(III) complexes, [Tb(TETA)] − and [Tb(TETA)(phen)] − (TETA = 1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetraacetate and phen = 1,10-phenanthroline), were synthesized and their luminescence ( 5 D 4 ! 7 F J=0-6 transitions) and magnetic properties were examined. The photoluminescence (PL) quantum yield of [Tb(TETA)(phen)] − (Q = 0.47) was significantly higher than that of [Tb(TETA)] − (Q = 0.006).The dramatic increase (78×) in green luminescence was attributed to intramolecular energy transfer from phen to Tb(III). The energy transfer rate according to Dexter theory was found to be approximately 10 11 s −1 . The temperature dependence of the molar susceptibilities confirmed that the two complexes behave as paramagnets obeying the Curie-Weiss law. In addition, the field-dependent magnetization of the two complexes measured in the −70 to + 70 kOe range at T = 1.8 K fitted well with the Brillouin function with the following values: g eff = 1.5, μ B = 9.27 × 10 −21 emu, and J = 6. These results provide new insights into the development of lanthanide metal complexes with tetraaza Results and DiscussionPL and Excitation Spectra. Figure 1(a) shows the PL spectra of the powdered Tb(III) complexes taken at 10 K. The PL spectra at RT (not shown) were similar but weaker Article

Photoconversion Mechanisms and the Origin of Second-Harmonic Generation in Metal Iodates with Wide Transparency, NaLn(IO3)4 (Ln = La, Ce, Sm, and Eu) and NaLa(IO3)4:Ln3+ (Ln = Sm and Eu)

“…Hence, multipole–multipole interactions should be considered. According to the Dexter’s theory, there are three types of multipolar interactions, that is, dipole–dipole (d–d), dipole–quadrupole (d–q), and quadrupole–quadrupole (q–q) interactions. , The multipolar interactions can be decided by the following equation: where I is the intensity of emission, x is the concentration of Sm 3+ cations greater than critical concentration ( x = 0.07), and K and β are constants for the given host under the same excitation condition. The Q is a constant for multipolar interactions and can have values of 6, 8, and 10, which are corresponding to d–d, d–q, and q–q interactions, respectively.…”

“…According to the Dexter's theory, there are three types of multipolar interactions, that is, dipole−dipole (d−d), dipole−quadrupole (d−q), and quadrupole−quadrupole (q−q) interactions. 46,47 The multipolar interactions can be decided by the following equation:…”

Evaluation of Point Group Symmetry in Lanthanide(III) Complexes – a New Implementation of the Continuous Symmetry Measure with Autonomous Assignment of the Principal Axis

“…Middle: Eu(ODA)3, redrawn with permission (CC BY-NC 4.0). 82 Right: Eu(pic)3•3(aza), redrawn with permission from reference 83 .…”

Blue-Light-Emitting Photostable Hybrid Films for High-Efficiency Large-Area Light Converter and Photonic Applications

“…Among them, lanthanide (Ln) ions, specifically Tb­(III) and Eu­(III), have been considered key components for designing green and red luminescent materials because they possess several unique luminescence properties, including hypersensitivity to their coordination environments, good color representation with narrow bandwidth, and millisecond luminescence lifetimes. Furthermore, the drawback arising from a very small f → f absorption coefficient can be overcome by introducing organic ligands as sensitizers. ,− However, no Ln­(III) ions appropriate for emitting a pure blue light have been reported. Only a handful of Ln­(III) complexes based on a few ligands, such as 1,8-naphthalimide derivatives, 1,3,5-benzenetricarboxylic acid, poly­(styrene-coglycidyl methacrylate), 1,10-phenanthroline, and N , N ′-bis­(salicylidene)-3,6-dioxa-1,8-diaminooctane (LH 2 ), have been realized as UV-to-red or UV-to-green conversion components. ,− In these complexes, the ligands play a key role in generating the light emissions.…”