Cubic aromaticity in ligand-stabilized doped Au superatoms.

Research paper by Omar O López-Estrada, Elli E Selenius, Bernardo B Zuniga-Gutierrez, Sami S Malola, Hannu H Häkkinen

Indexed on: 06 Sep '21Published on: 10 Jul '21Published in: The Journal of chemical physics


The magnetic response of valence electrons in doped gold-based M@AuL superatoms (M = Pd, Pt, Ag, Au, Cd, Hg, Ir, and Rh; L = PPh; and q = 0, +1, +2) is studied by calculating the gauge including magnetically induced currents (GIMIC) in the framework of the auxiliary density functional theory. The studied systems include 24 different combinations of the dopant, total cluster charge, and cluster structure (cubic-like or oblate). The magnetically induced currents (both diatropic and paratropic) are shown to be sensitive to the atomic structure of clusters, the number of superatomic electrons, and the chemical nature of the dopant metal. Among the cubic-like structures, the strongest aromaticity is observed in Pd- and Pt-doped M@AuL clusters. Interestingly, Pd- and Pt-doping increases the aromaticity as compared to a similar all-gold eight-electron system AuL . With the recent implementation of the GIMIC in the deMon2k code, we investigated the aromaticity in the cubic and butterfly-like M@Au core structures, doped with a single M atom from periods 5 and 6 of groups IX-XII. Surprisingly, the doping with Pd and Pt in the cubic structure increases the aromaticity compared to the pure Au case not only near the central atom but encompassing the whole metallic core, following the aromatic trend Pd > Pt > Au. These doped (Pd, Pt)@Au nanoclusters show a closed shell 1S1P superatom electronic structure corresponding to the cubic aromaticity rule 6n + 2.