Importance of the chromophore orientation to the ligand-to-metal energy transfer in lanthanide complexes with pendant-arm fitted cyclen derivatives

Abstract

IIIAt first sight, trivalent lanthanide ions Ln are not very attractive to the chemist: the spherical entities with ''inner'' 4f valence electrons interact electrostatically with their surroundings, display little stereochemical preferences, and have very similar chemical behavior. On the other hand, these ions exhibit rich and unique spectroscopic and magnetic properties that can be taken advantage of either for spectroscopic and magnetic probes, or to construct materials with specific physico-chemical properties. Moreover, the intrinsic III chemical drawbacks of the Ln ions can be turned into a benefit since the ions adapt easily to almost any chemical environment and can therefore be readily introduced into a variety of ionic, molecular, and supramolecular edifices where they act as functional centers. We will III III first outline the historical aspects of Ln coordination chemistry. Fundamental properties of the Ln ions, including coordination numbers and geometries, solvation, hydrolysis and thermodynamic aspects of complexation, are then briefly reviewed. We finally focus on the several methods developed by inorganic chemists to trap the elusive lanthanide ions into environments preserving or even enhancing their physical properties, or increasing the differences in their chemical characteristics.

Structure, Dynamics, and Computational Studies of Lanthanide‐Based Contrast Agents

“…These include unsubstituted aliphatic (5, 7-14) [417][418][419][420][421], aromatic (4, 15-20) [421][422][423][424] and heterocyclic (6, 21-23) [420,[424][425][426] hydrocarbon chains, as well as carboxylate and ester groups (24)(25)(26)(27)(28)(29)(30)(31) [417,418,420,421,426,427], ketone (32) [428], phosphonate (33) and phosphinate (34) [417,421,424] groups, as well as dipeptides (35 and 36) [429], and methylated β-cyclodextrin (37) [422] complexes have nine-coordinate TSA geometries. The solution TSA/SA composition of several tetraamide complexes was studied by 1 H NMR, where the signature of these two isomers is easily seen since the macrocyclic H 4 proton has very different PCS values in the two isomers.…”

Magnetic and Luminescent Properties of Sm, Eu, Tb, and Dy Coordination Polymers with 2‐Hydroxynicotinic Acid

“…Thus, Ln1 and Ln2 are linked by carboxylic groups to construct a 2D layer structure composed of rhombic grids (Figure 3, b). [43][44][45] Magnetic susceptibility measurements of 1-6 were performed in a direct-current (dc) field of 1 kOe in the 2-300 K range. They are shown in Figure 5.…”

Small Molecule Luminescent Lanthanide Ion Complexes - Photophysical Characterization and Recent Developments

“…Anthracene -solid state in PMMA 22 [70] [Ru(bpy)3]Cl2 2.8 (air saturated water at room temperature)/37.6 (methanol at 77 K) [71,72] 5x10 -6 M quinine sulfate in 0.1 N H2SO4 -air saturated 54.6 [73] 1 μM Sm 3+ in the Wallac DELFIA Enhancement Solution 1.5 [58] Rhodamine 6G -air saturated water 81 [74] Eu(III) chelate of N,N,N',N'-[4'-phenyl-2,2':6',2''-terpyridine-6,6''-diyl]bis(methylenenitrilo)tetrakis(acetate) -deoxygenated -air saturated water 16 [44] Yb(tta)3(H2O)2 0.35 (deoxygenated toluene)/0.55 (solid state in PMMA) [75] nonadentate. Of all of the ligands investigated, the bipyridine-based octadentate ligands 5-7 demonstrated to be efficient sensitizers, with quantum yields around 0.22 to 0.38%.…”