New global minimum conformers for the Pt and Pt clusters: low symmetric species featuring different active sites.

Context: The study of platinum (Pt) clusters and nanoparticles is essential due to their extensive range of potential technological applications, particularly in catalysis. The electronic properties that yield optimal catalytic performance at the nanoscale are significantly influenced by the size and structure of Pt clusters. This research aimed to identify the lowest-energy conformers for Pt , Pt , and Pt species using Density Functional Theory (DFT).

Does Aromaticity Play a Role in Electronic and Structural Properties of YB (n=2-14) Clusters?

Nanoclusters exhibit electronic, optical, and magnetic properties that differ significantly from those of extended and molecular systems with comparable stoichiometries. In this work, we examined the structural, energetic, and electronic characteristics of yttrium-doped boron clusters (YB, where n ranges from 2 to 14) with the aid of robust wavefunction analysis tools. Special emphasis is placed on the elucidation of the potential aromatic character exhibited by the resultant molecules and how it can affect their chemical bonding and stability.

Structure and isomerization behavior relationships of new push-pull azo-pyrrole photoswitches.

A family of stilbenyl-azopyrroles compounds 2a-d and 3a-d was efficiently obtained a Mizoroki-Heck C-C-type coupling reaction between 2-(4'-iodophenyl-azo)--methyl pyrrole (1a) and different vinyl precursors. The influence of the π-conjugated backbone and the effect of the pyrrole moiety were correlated with their optical properties. Studies UV-Visible spectrophotometry revealed that the inclusion of EWG or EDG favors a red-shift of the main absorption band in these azo compounds compared with their non-substituted analogues.

Synthesis of Functionalized Tetrasubstituted Allenes by the Addition of Bis(trimethylsilyl)ketene Acetals to Ynones Catalyzed by Gold(I).

We have developed a straightforward and rapid methodology for the synthesis of tetrasubstituted allenes bearing carboxylic acids in the 1,3-position through the gold(I)-catalyzed nucleophilic addition of bis(trimethylsilyl)ketene acetals to ynones. The reaction was evaluated with several substrates, and 21 allenes were obtained in moderate to good yields. Using DFT calculations, we studied the mechanism of the reaction, which suggested a nucleophilic 1,4-addition pathway.

On the structure and electronic properties of Pt clusters: new most stable structures for = 16-17.

The lowest energy structures and electronic properties of Pt clusters up to = 17 are investigated by using a genetic algorithm in combination with density functional theory calculations. There are several putative global minimum structures for platinum clusters which have been reported by using different approaches, but a comprehensive study for = 15-17 has not been carried out so far. Herein, we perform a consensus using GGA (PBE), meta-GGA (TPSS) and hybrid (B3PW91, PBE0, PBEh-3c, M06-L) functionals in conjunction with the Def2-TZVP basis set.