2.1.8. Michael Reaction 2245 2.1.9. Others 2247 2.2. Cyclization Reactions 2248 2.2.1. Carbon Diels−Alder Reactions 2248 2.2.2. Aza-Diels−Alder Reactions 2252 2.2.3. Other Hetero-Diels−Alder Reactions 2255 2.2.4. Ionic Diels−Alder Reaction 2256 2.2.5. 1,3-Dipolar Cycloadditions 2256 2.2.6. Other Cycloaddition Reactions 2258 2.2.7. Prins-type Cyclization 2259 2.3. Friedel−Crafts Acylation and Al...

Rare earth metal doped silica nanoparticles have significant advantages over traditional organic dyes and quantum dots. Silsesquioxanes are promising precursors in the production of silica nanoparticles by thermolysis, due to their structural similarities with silica materials. This manuscript describes the production of a new Eu3+-based metallasilsesquioxane species and its use as a single sou...

The electronic and optical properties of the rare earth metal atom-doped anatase TiO₂ have been investigated systematically via density functional theory calculations. The results show that TiO₂ doped by Ce or Pr is the optimal choice because of its small band gap and strong optical absorption. Rare earth metal atom doping induces several impurity states that tune the location of valence and co...

Computing the enthalpies of formation for alkali metal and alkaline earth metal oxides (M(x)O) and hydroxides [M(OH)(n)] using the Gaussian-n (Gn) and Weismann-n (Wn) ab initio model chemistries is difficult due to an improper treatment of core-valence electron correlation effects. Using a new model chemistry called the correlation consistent Composite Approach (ccCA), enthalpies of formation w...

The concentrations of the rare earth elements (REE) in surface waters and sediments, when normalized on an elementby-element basis to one of several rock standards and plotted versus atomic number, yield curves that reveal their partitioning between different sediment fractions and the sources of those fractions, for example, between terrestrial-derived lithogenous debris and seawater-derived b...

p-Nitrocalix[6]arene (CALX-N6, L) formed a 1:1 metal complex, ML, with light rare earth metal ions (M3+), such as La3+, Pr3+ and Nd3+ except Ce3+, but formed a 1:2 (M(3+):L) complex, ML2 (the charge of the complex is omitted) with heavy rare earth metal ions, such as Sm(3+)-Lu3+ including Y3+. The conditional stability constants of these 1:1 and 1:2 complexes, KML and KML2, were measured by a l...

Four multitopic Schiff-base ligand precursors were synthesized via condensation of 4,4'-diol-3,3'-diformyl-1,1'-diphenyl or 1,3,5-tris(4-hydroxy-5-formylphenyl)benzene with 2,6-diisopropylaniline or 2,6-dimethylaniline. Amine elimination reactions of Ln[N(SiMe(3))(2)](3) (Ln = La, Nd, Sm or Y) with these multitopic ligand precursors gave ten heterogeneous rare-earth metal catalysts. These heter...