Chemical bonding in the pentagonal-pyramidal benzene dication and analogous isoelectronic hexa-coordinate species

Publication date: Available online 18 March 2017 Source:Computational and Theoretical Chemistry Author(s): Felipe Fantuzzi, David Willian Oliveira de Sousa, Marco Antonio Chaer Nascimento The nature of the chemical bond in the pentagonal-pyramidal benzene dication and related species was described by Modern Valence Bond calculations and the Generalized Product Function Energy Partitioning method. The results suggest that the π space of C6H6 2+ is composed of a donor-acceptor bond from a cyclopentadienyl anion moiety, described as a 5c–6e π bonding, to a triply charged Lewis acid CH structure. Similar results were found for isoelectronic species, such as C5H5BH+, C5H5BeH, and C5H5LiH−, leading to different main-group hexa-coordinate atom-bearing structures. A pictorial mechanism for the bonding of the studied molecules was constructed, and different geometrical and electronic features could be explained by this straightforward model. Finally, the results suggest that several poly-coordinate atom-containing molecules, sandwich-type compounds, oligomers, and polymers could be formed by the interaction of a π system and Lewis acid moieties. Graphical abstract

Source: Computational and Theoretical Chemistry - March 24, 2017 Category: Chemistry Source Type: research