Increased Luminescent Lifetimes of Ln3+ Complexes Emitting in the Near-Infrared as a Result of Deuteration

Abstract

The luminescence of lanthanide(III) ions emitting in the nearinfrared region is ideally suited for telecommunications applications, and a number of applications have been developed. These are in general based on inorganic matrices, but polymer-based matrices would have advantages in device fabrication. In organic matrices, however, molecular vibrations in the matrix quench the excited state of luminescent lanthanide ions. Replacement of strongly quenching groups such as C−H oscillators by more weakly quenching

Synthesis, crystal structure and luminescent properties of Er2Te4O11

“…The shoulder bands nearby may be originated from the split of the above transitions by ligand field, since the Er(III) ion has a low symmetry of C1. The luminescent lifetime for the emission band at 1538 nm is measured to be about 0.275 ms, which is much longer than those of erbium(III) complexes with organic ligands [8]. The low value of the lifetime for the lanthanide complexes with organic ligands compared with the ions in inorganic matrices is due to the quenching of the luminescent state by high-frequency vibrations in the ligand and the solvent.…”

“…Near IR luminescent spectrum of the title compound upon excitation at 521 nm indicates two emission bands at 981 nm (weak) and 1538 nm (strong), respectively (Fig. 3), which correspond to the 4 I 11/2 → 4 I 15/2 , and 4 I 13/2 → 4 I 15/2 transitions, respectively [8]. The shoulder bands nearby may be originated from the split of the above transitions by ligand field, since the Er(III) ion has a low symmetry of C1.…”

Synthesis, characterization and oscillator-vibrated near-infrared (NIR) luminescence of two pseudo-polymorphic [Yb4((OH)2-Salophen)4] complexes

“…Both demonstrate that the NIR luminescent property of the Yb 3+ ion in complexes 2 and 5 is sensitive to solvents-based oscillator vibrations within the inner coordination spheres of Yb 3+ ions. As a matter of fact, the NIR emission of Ln 3+ ions critically depends on the coupling of the excited state of Ln 3+ ion with vibrations of nearby oscillators [31]. Moreover, the relatively lower frequency (m sym = 2900-3100 cm À1 ) of ACH vibration than that (m sym = 3400-3700 cm À1 ) of AOH vibration has a negative influence on the effectiveness of luminescence [32].…”

Relationship Between the Ligand Structure and the Luminescent Properties of Water‐Soluble Lanthanide Complexes Containing Bis(bipyridine) Anionic Arms

“…The three water molecules link the protonated O5 atom from the carboxylate function of a [EuA C H T U N G T R E N N U N G (L 3 H 2 )Cl] + molecule at (x, y, z) to the unprotonated O7 atom of a molecule at (1Àx, 1Ày, Àz) in a cooperative hydrogen-bond network to form a layer structure parallel to the Àab plane ( Figure S1, in the Supporting Information). The hydrogen-bond ring pattern formed is of graph set R 4 5 (8). [34] The stabilisation is increased by a single p-p stacking interaction.…”

“…The role of the ligand is first to absorb light and to transfer this excess energy to the lanthanide excited states, but also to complete the first coordination sphere of the metal in order to prevent luminescence quenching due to vibrational deactivation through O À H, N À H and C À H oscillators of the solvent molecules. [7,8] The overall luminescence Abstract: A series of six new ligands (L 1 -L 6 ) suitable for the formation of luminescent lanthanide complexes in water is described. Ligands L 1 -L 4 are constructed from two 6'-carboxy-6-methylene-2,2'-bipyridine chromophoric arms bonded to the amino function of a 2-aminomethylene-6-carboxy-pyridine (L 1 ), an N,N-diacetate-ethylene diamine (L 2 ), a serine (L 3 ), or an aminomalonic acid (L 4 ).…”