Starlike aluminum-carbon aromatic species

Abstract

Is it possible to achieve molecules with starlike structures by replacing the H atoms in (CH)nq aromatic hydrocarbons with aluminum atoms in bridging positions? Although D4h C4Al 42- and D2 C6Al6 are not good prospects for experimental realization, a very extensive computational survey of fifty C5Al5- isomers identified the starlike D5h global minimum with five planar tetracoordinate carbon atoms to be a promising candidate for detection by photoelectron detachment spectroscopy. BOMD (Born-Oppenheimer molecular dynamics) simulations and high-level theoretical computations verified this conclusion. The combination of favorable electronic and geometric structural features (including aromaticity and optimum C-Al-C bridge bonding) stabilizes the C5Al 5- star preferentially. © 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim.