A DFT study on the isomerization mechanism of azobenzene derivatives on silicon substrates

The cis–trans isomerization mechanism of azobenzenesulfonamide derivatives on silicon substrates was investigated using DFT. The most favorable cooperative mode of the N2 inversion of the L followed by the N1 inversion of the R was proposed.

DFT simulation towards evaluation the molecular structure and properties of the heterogeneous C16Mg8O8 nano-cage as selective nano-sensor for H2 and N2 gases

Adsorption of hydrogen (H₂) and nitrogen (N₂) molecules was analyzed on a new fullerene-like C₁₆Mg₈O₈ nano-cage, composed of magnesium, oxygen, and carbon, using density functional theory. A detailed analysis of the energy, geometry, and electronic structure of various H₂ and N₂ adsorptions on the cluster surface was performed. The adsorption energies of H₂ and N₂ were estimated to ranging from -0.16 to -0.52eV, respectively. The most stable adsorption configurations were those in which the H or N atoms of the adsorbates were located near the Mg atom of the cluster surface at different sides. It was found that the heterogeneous C₁₆Mg₈O₈ nano-cluster selectively act against the H₂ and N₂ gaseous molecules. The electrical conductivity of the cluster, arising from HOMO/LUMO energy gap, was more sensitive to N₂ gaseous molecule rather than H₂ one, indicating that the heterogeneous C₁₆Mg₈O₈ nano-cage may be potential nano-sensor for N₂ molecule. These findings were specified by analyzing the characteristics in the electron density of states (DOS).