: We summarize our contributions on the quest of new planar tetracoordinate carbon entities (new carbon molecules with exotic chemical structures and strange bonding schemes). We give special emphasis on the rationalization why in this type of molecules the planar configuration is favored over the tetrahedral one. We will concentrate on the latter and will show that molecules containing planar tetracoordinate carbons have a stabilizing system of delocalized electrons, which shows similar properties as systems in aromatic molecules. q 2006 Wiley Periodicals, Inc. J Comput Chem 28: 362–372, 2007 Key words: planar tetracoordinate carbon; aromaticity; magnetic properties; electron delocalization Background It is fascinating to see and to understand the chemical structure of molecules. The chemical structure is a consequence not only of their constituent elements but also of the way those atoms are connected to each other, and what their special arrangement is. So, the chemical struc...
Gabriel Merino, Miguel A. Méndez-Rojas, Alb