New Insights into Adsorption Properties of the Tubular Au26 from AIMD Simulations and Electronic Interactions

Abstract

Recently, we revealed the electronic nature of the tubular Au26 based on spherical aromaticity. The peculiar structure of the Au26 could be an ideal catalyst model for studying the adsorptions of the Au nanotubes. However, through Google Scholar, we found that no one has reported connections between the structure and reactivity properties of Au26. Here, three kinds of molecules are selected to study the fundamental adsorption behaviors that occur on the surface of Au26. When one CO molecule is adsorbed on the Au26, the σ-hole adsorption structure is quickly identified as belonging to a ground state energy, and it still maintains integrity at a temperature of 500 K, where σ donations and π-back donations take place; however, two CO molecules make the structure of Au26 appear with distortions or collapse. When one H2 is adsorbed on the Au26, the H–H bond length is slightly elongated due to charge transfers to the anti-bonding σ* orbital of H2. The Au26-H2 can maintain integrity within 100 fs at 300 K and the H2 molecule starts moving away from the Au26 after 200 fs. Moreover, the Au26 can act as a Lewis base to stabilize the electron-deficient BH3 molecule, and frontier molecular orbitals overlap between the Au26 and BH3.