Electronically controlled O 2 activation on XAu 12 (X = IIIA–VIA) clusters, including novel 16-electron superatoms

Abstract Benefiting from the aurophilicity and relativistic effects of gold, gold clusters exhibit uniquely intricate atomic stacking patterns and diverse superatomic orbital configurations. Our previous studies identified a series of 14-electron magnetic superatomic clusters, X@Au 12 (X = Cr, Mn, Fe, Co) and 18-electron superatomic clusters with dual closed-shell geometric and electronic configurations X@Au 12 (X = Mo, W). In this work, through single-atom doping of Au 12 with Group IIIA–VIA elements, we successfully constructed novel 16-electron superatomic clusters, XAu 12 (X = S, Se, Te). Despite the inherently weak bonding interactions and limited charge transfer between S/Se/Te atoms and the Au 12 fragment, the meteor-dart-shaped architecture, characterized by low C s symmetry, effectively mitigates inter-fragment Pauli repulsion and induces a sizeable highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) gap. Subsequently, by investigating O 2 adsorption behaviors on typical clusters with distinct superatomic properties (SnAu 12 , Cr@Au 12 , Mo@Au 12 , Te(Se)Au 12 ), we established a regulatory mechanism for modulating oxidation reactivity through superatomic electronic properties. O 2 adsorption on clusters proceeds via electron transfer mechanisms, demonstrating that oxidative activity is governed by the HOMO level and the HOMO-LUMO gap. Within the framework of the jellium model, the theoretically predicted adsorption energy trend—SnAu 12 ≈ Cr@Au 12 < TeAu 12 ≈ SeAu 12 < Mo@Au 12 —is in excellent agreement with our calculation results (−0.89 eV ≈ −0.84 eV < −0.64 eV ≈ −0.63 eV < −0.62 eV). This study provides fundamental design principles for exploring superatomic clusters featuring sub-closed-shell or even open-shell electronic configurations, while also highlighting their potential for catalytic and functional applications.