Tuning of aromaticity and reactivity in gold-substituted cyclopropenyl cations

Abstract

This study investigate the structural, electronic, and reactivity properties of the aurocarbon C₃H₂Au⁺, C₃HAu₂⁺, and C₃Au₃⁺ clusters. A potential energy surface exploration indicates that the most stable isomers adopt cyclic structures, supporting the gold–hydrogen analogy in these cationic systems. These cyclic forms preserve the characteristic geometry of the cyclopropenyl cation, with covalent C–Au interactions confirmed by multiple bonding analyses. All three systems exhibit a delocalized 3c–2e π-bond across the carbon ring, consistent with an aromatic behavior. The substitution of hydrogen by gold alters local reactivity patterns.