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The computations on the ] system is presented in order to clarify the structures of its two known isomers. The computations have indicated that the major species should have the isolated pentagon rule (IPR) cage, while the minor one should contain one pentagon-pentagon junction in the carbon cage.

The article presents a newly developed simple and low-cost hydrothermal method, which can be employed for the synthesis of the ytterbium silicate nanoparticles. The results demonstrate the exhibition of low thermal conductivity and high structural stability of the compounds.

The article explains the thermodynamics, as well as the kinetics that are involved in the reactions of various different lanthanides, actinides and transition- and heavy-metal cations. The mechanisms associated with the complexation reactions of these compounds are also discussed.

The article explains a new strategy that can be employed for the orthogonal activation of propargyl and n-pentenyl glycoside s. The approach is shown to be effective for the activation of various orthoesters as well.

The synthesis of [n,5]-spiroketals (n = 5, 6) via use of exocyclic enol ethers as starting materials is reported. Addition of catalytic amounts of the Lewis acid [Yb(OTf).sub.3] is observed to facilitate the ring enlargement and increase the yield of the corresponding spiroketal in many synthesis examples.

The application of ytterbium triflate as an efficient catalyst for addition of amines to carbodiimides to N,N',N'-trisubstituted guanidines is described. The reaction is demonstrated the wide scope of amines under solvent-free condition.

Ytterbium(III) triflate-catalyzed ring opening of substituted 1-cyclopropyl-2-propyn-1-ols with sulfonamdies as an efficient route to conjugated enynes is described. The reaction is operationally straightforward and is accomplished in regioselective manner in all except one case under mild conditions.

The synthesis and single crystal structure of the isostructural rare-earth titanium antimonides [RE.sub.2][Ti.sub.11]-[x.sub.Sb.sub.14]+x (RE = Sm, Gd, Tb, Yb) by using arc-melting reactions of the elements is reported. The structure is found to consist of titanium-centered octahedra (CN6) and pentagonal bipyramids (CN7) connected to form a 3D framework whose cavities are filled with RE atoms and the resistivity measurements for samarium and ytterbium members indicated metallic behavior.

Reductive amination of prochiral unhindered 2-alkanones with(S)-[alpha]-MBA in the presence of Yb[(OAc).sub.3], Raney-Ni and hydrogen has resulted in increased diastereoselectivity for the amine products. An in situ cis- to trans-ketimine isomerization mechanism is described to account for the increase in diastereoselectivity.

The defect chemistry of [Yb.sup.3+]:CaTi[O.sub.3] perovskite solid solutions is examined. Yb-doped CaTi[O.sub.3] ceramics are prepared by sintering and the dielectric properties of the final materials are measured as a function of temperature and frequency.

The syntheses, spectroscopic and structural properties of a series of cyanoruthenate complexes of hexaazatriphenylene are described. The Ru-based emission in the Nd(III) analogues is quenched by Ru->Lu photoinduced energy transfer, thus resulting in sensitized near-infrared luminescence from Yb(III) and Nd(III).

The synthesis and structure of an ytterbium(II) hydride complex that is soluble in hydrocarbons is described. It shows an unusual high stability toward ligand exchange.

A new imidazolidine-bridged bis(phenol) is prepared by a simple Mannich reaction and a series of lanthanide derivatives supported by this ligand are synthesized by direct salt metathesis reaction. A novel bimetallic ytterbium dichloride is used as a precursor to prepare a series of ytterbium derivatives by direct salt metathesis reactions and the bulkiness of the reagents has profound effect on the outcome of these reactions.

A high yield patterning techniques, involving the inducement of high voltage damage into the glass matrix is used to study and explain the patterning and periodic nanaostructuring of Er/Yb-codoped IOG1 phosphate glass by the Bragg reflectors. The ultraviolet laser-assisted method of selective chemical etching is being widely used to obtain deeper grating structures, which are commonly used in several waveguide laser devices.

The valency of Yb ion in YbIn[Au.sub.2] is determined by the Yb [L.sub.III]-edge x-ray absorption near edge structure spectroscopy at high pressure and the lattice compression curves of YbIn[Au.sub.2] and LuIn[Au.sub.2] compounds are observed by the x-ray diffraction measurement using intense synchrotron radiation x-ray sources. The results have shown that the valence state of Yb ion in YbIn[Au.sub.2] is strongly correlated to the unit-cell volume so that the magnetic 4[f.sup.13] state is stabilized at high pressure.