Contrast of Bonding and Characters for C6, B3N3, C6H6 and B3N3H6 Molecules

Abstract Through integrative consideration of NICS, MO, MOC and NBO, we precisely investigated delocalization and bonding characters of C6, C6H6, B3N3 and B3N3H6 molecules. Firstly, we originally discovered and testified that C6 cluster was sp2 hybridization. Negative NICS values in 0 and 1 Å indicated that C6 had δ and Π aromaticity. Secondly, B3N3 with sp2 hybridization had obvious δ aromaticity. Finally, WBI values approved that there were delocalization in C6, C6H6 and B3N3 molecules, but B3N3H6 structure did not have delocalization with the WBI 1.0. Moreover, total WBI values of carbon, boron and nitrogen atoms were four, three and three, respectively. Namely, the electrons of B3N3H6 and B3N3 were localized in nitrogen atoms and they did not form delocalized bonding. In a word, bonding characters of carbon, boron and nitrogen atoms were dissimilar although the molecules composed of carbon, boron and nitrogen were regarded as isoelectronic structures.