Behaviour of ‘free-standing’ hollow Au nanocages at finite temperatures: a BOMD study

A DFT study on the adsorption of nucleobases with Au20

The interactions of nucleobase with Au₂₀ cluster were studied utilizing density functional theory (DFT). We find that the nucleobases were attached with Au₂₀ through Au-N or Au-O bonds. The orders of calculated adsorption energy are cytosine > adenine > guanine > thymine. The maximum adsorption energy is - 0.787 eV which belongs to the adsorption of cytosine on Au₂₀ cluster. Our calculations show that the HOMO-LUMO gaps of Au₂₀ are significantly decreased by the nucleobase adsorption, suggesting the potential detection for nucleobases. The interactions between Au₂₀ and nucleobases are revealed through the QTAIM analysis. The NBO analysis was investigated for the electron transfer of donor-acceptor of all types of complexes. The IR and UV-vis spectra were simulated for the further identification in the experiment.

Au26: a case of fluxionality/co-existence

BOMD simulations are performed on experimentally identified conformations of the fluxional Au26 cluster at finite temperature. Comprehensive analysis of structural, electronic and thermal properties indicates that the highest energy tubular cage conformation (till 500 K) outperforms the ground state conformation (till 400 K) in terms of thermal stability.