Lanthanide complex with

NMR investigation of molecular structure of paramagnetic lanthanide complexes with crown ethers in solutions 98ZSK714. 

Eu(III) complexes of quinolinecarboxylic acids, including 5, were studied (00MI31). Those of complexes of 5 with Eu(III) and Tb(III) ion were studied, and they were applied for analysis of 5 in medicinal preparations (00UKZ115). Stability of lanthanide complexes with 5 was studied (00MI67). The fluorescence spectra of 5 complexed with Co(II) and ATP was measured (01SA(A)1317). 

Figure 7 Luminescent lanthanide complexes with representative luminescence lifetimes, and hydration states (derived from luminescence measurements) where appropriate.

Lanthanide complex with the enhancing ligand L is luminescent... 

As a result of their low redox potentials [173], bis(phthalocyaninato) lanthanide complexes are often inadvertently reduced or oxidized, and they are also very sensitive to acids and bases. In order to solve these problems, Veciana et al. achieved certain success on designing a series of novel compounds with characteristics that would give them improved redox stability. Electroactive ligands based on phthalo-cyaninato tetra dicarboximide [175] or perfluorinated phthalocyanine [176] were used to assemble the double-decker lanthanide complexes, with the effect of stabilizing the negative charge of the anionic state of the compounds, which resulted in a strong shift of 0.7 V of their first oxidation potentials. 

The trend toward greater complex stability with increasing lanthanide atomic number (see Table 3 for EDTA, DCTA, and DTPA complexes) has also been demonstrated for lanthanide complexes with... 

Cross J-P, Lauz M, Badger PD et al (2004) Polymetallic lanthanide complexes with PAMAM-naphthalimide dendritic ligands luminescent lanthanide complexes formed in solution. J Am Chem Soc 126 16278-16279... 

Probably, the first series of lanthanide complexes with neutral oxygen donor ligands is that of AP with the lanthanide nitrates. In 1913, Kolb (79) reported tris-AP complexes with lighter lanthanide nitrates and tetrakis-AP complexes with heavier lanthanide nitrates. Subsequently, complexes of lanthanide nitrates with AP which have a L M of 6 1 and 3 1 have also been prepared (80-82). Bhandary et al. (83) have recently shown through an X-ray crystal and molecular structure study of Nd(AP)3(N03)3 that all the nitrates are bidentate and hence the coordination number for Nd(III) is nine in this complex. Complexes of AP with lanthanide perchlorates (81, 84), iodides (81, 85), and isothiocyanates (66, 86, 87) are known. While the perchlorates and iodides in the respective complexes remain ionic, two of the isothiocyanates are coordinated in the corresponding complexes of AP with lanthanide isothiocyanates. 

The Lu—C cr-bonding distances range from 2.425(15) to 2.501(17) A. These distances are approximately 0.2 A shorter than the corresponding distance for a pentahapto cyclopentadienide lutetium bond as predicted from ionic radii. Coordination about the lutetium atom is a slightly distorted tetrahedron. The formal coordination number of four is extremely low for the lanthanides. The only other lanthanide complex with such a low coordination number is the 3-coordinate compound [Lu N(SiMes)2 3] 131). In both cases, the low coordination number is stabilized by the use of bulky hgands. 

Butter et al (221) prepared some lanthanide complexes with an interesting quadridentate N-donor Ugand, l,2-di(p5u idine-2-aldiminoethane) (abbreviated as PAIE) to study the fluorescence spectra in order to determine the site symmetry of the lanthanide ions in these complexes. Recently M-ul-Haque et al. (222) have... 

Fig. 41. A plot of the M—N distances in lanthanide complexes with different coordination numbers...

Renaud, F. Piguet, C. Bernardinelli, G. Biinzli, J.-C. G. Hopfgartner, G. In search for mononuclear helical lanthanide building blocks with predetermined properties lanthanide complexes with diethyl pyridine-2,6-dicarboxylate. Chem. Eur. J. 1997, 3(10), 1660-1667. 

Zucchi, G. Scopelliti, R. Biinzli, J.-C. G. Importance of the chromophore orientation to the ligand-to-metal energy transfer in lanthanide complexes with pendant-arm fitted cyclen derivatives. J. Chem. Soc., Dalton Trans. 2001, (13), 1975-1985. 

In many cases, the inflexions present in the plots of AH and AS vs. atomic number compensate, leading to much smoother curves for corresponding plots of AG or K. Examples of this type of behaviour are shown in reference 405, where values of AG, AH and AS for lanthanide complexes with edta and related ligands are plotted. Extensive lists of association constants for edta-type and other carboxylate ligands have been given.414,415... 

It is also often assumed that A is constant along a series of lanthanide complexes with the same ligand. The mechanism providing spin density delocalization from the metal to the ligands is due to a weak covalent bonding involving the 6s metal orbital, which, in turn, can transfer unpaired spin density on nearby nuclei through spin polarization from 4f orbitals [82]. 

Berthon, C., Guilbaud, P., Bousquet, M., Gimenez, C. 2002. Structural studies by NMR and molecular dynamic calculations of lanthanide complexes with ethoxy malonamides in solution. In ISEC 02, Proc Int Solvent Extr Conf. Sole, K.C., Cole, P.M., Preston,... 

Stability Constants (log P aN, ) of Lanthanide Complexes with OOCMPO and CPw2, CPw3, CPw17, and CPn3 in MeOH (/ = 0.05 M) Determined by UV Spectrophotometry... 

Lactones, via indium compounds, 9, 686 Lactonizations, via ruthenium catalysts, 10, 160 Ladder polysilanes, preparation and properties, 3, 639 Lanthanacarboranes, synthesis, 3, 249 Lanthanide complexes with alkenyls, 4, 17 with alkyls, 4, 7 with alkynyls, 4, 17 with allyls, 4, 19 with arenes, 4, 119, 4, 118 and aromatic C-F bond activation, 1, 738 bis(Cp ), 4, 73... 

Application of the model-free methods to axial bimetallic lanthanide complexes with sterically rigid ligands... 

Lanthanide complexes with axial symmetry (i.e., possessing at least a threefold axis, see sect. 2.4.2) are exclusively considered because the principal magnetic z axis coincides with the molecular symmetry axis (Forsberg et al., 1995) and the c 2 spherical tensor operators do not contribute to the crystal-field potentials (Gorller-Walrand and Binne-mans, 1996). The rhombic term of Bleaney s approach V6B Hi (eqs. (42), (46)) thus vanishes and the crystal-field independent methods (eqs. (51), (53)) can be used without complications. 

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