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The potential energy surfaces of the [Si.sub.5][Li.sub.n.sup.5-6] (n = 5?7) systems were explored in detail to find feasible way to design three-dimensional star-like silicon structures using the appropriate ligands. The calculation results revealed that the important contribution of ionic character of the Si-Li interactions to induce the formation of a bridged structure and the contribution of reduction of the Pauli repulsion and the maximization of the orbital towards formation of star-like structure.

The [C.sub.5.sup.2-] skeleton in combination with saturated hydrocarbon fragments is used to obtain a series of planar tetracoordinate carbon molecules in cyclic semisaturated hydrocarbons. The system is the first example of semisaturated cycles containing a planar tetracoordinate carbon stabilized only by electronic factors.

The potential energy surface of C6Li6 was re-examined and a new non-symmetric global minimum was found. The new structure can be described as three C22− fragments strongly aggregated through lithium bridges. At high temperatures, fluxionality is perceived instead of dissociation. At 600 and 900 K, the BOMD simulations show that the lithium mobility is high, indicating that the cluster behaves in a liquid-like manner (BOMD=Born-Oppenheimer molecular dynamics). [ABSTRACT FROM AUTHOR]

Highlights: [•] We report the putative global minima configurations of neutral copper sulfide (CuS) N clusters (N =1–6), obtained by DFT. [•] The HOMO–LUMO gap ranges from 1.3 to 3.3eV making these clusters suitable candidates for photocatalysis. [•] As cluster size increases, the sub-nanoclusters studied here tend to form a Cu-core capped with S atoms. [Copyright &y& Elsevier]

The potential energy surfaces of the LinSi4- (n = 0-5) clusters were explored using the Kick Coalescence method. We found that, for those systems with n ≤ 2, the butterfly and parallelogram Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. kernels prevail as building blocks; however, when n ≤ 3, the Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. tetrahedral kernel, which is commonly found in heavier alkali monosilicides, MSi (M = Na, K, Rb, Cs), arises as the prevailing building block. In addition, by a natural population analysis (NPA) we found that the maximum charge transfer -4 from Li atoms to Si atoms is attained when n ≤ 3. The addition of more Li atoms to the Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. system does not increase the charge transfer, but keeps it almost constant at the maximum value. We also calculated theoretical vertical electron detachment energies (VDEs) for low- lying isomers of the Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. (n = 0-4) clusters in order to facilitate their experimental identification. [ABSTRACT FROM AUTHOR]

The potential energy surface of C6 Li6 was re-examined and a new non-symmetric global minimum was found. The new structure can be described as three C2 (2-) fragments strongly aggregated through lithium bridges. At high temperatures, fluxionality is perceived instead of dissociation. At 600 and 900 K, the BOMD simulations show that the lithium mobility is high, indicating that the cluster behaves in a liquid-like manner (BOMD=Born-Oppenheimer molecular dynamics)., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Is it possible to achieve molecules with starlike structures by replacing the H atoms in (CH)(n)(q) aromatic hydrocarbons with aluminum atoms in bridging positions? Although D(4h) C(4)Al(4)(2-) and D(2) C(6)Al(6) are not good prospects for experimental realization, a very extensive computational survey of fifty C(5)Al(5)(-) isomers identified the starlike D(5h) global minimum with five planar tetracoordinate carbon atoms to be a promising candidate for detection by photoelectron detachment spectroscopy. BOMD (Born-Oppenheimer molecular dynamics) simulations and high-level theoretical computations verified this conclusion. The combination of favorable electronic and geometric structural features (including aromaticity and optimum C-Al-C bridge bonding) stabilizes the C(5)Al(5)(-) star preferentially., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)