Structure and electron delocalization of the boron oxide cluster B3(BO)3 and its anion and dianion

The isomers of B6O3, B 6 O 3 - and B 6 O 3 2 - were studied using DFT, MP2 and G3B3 methods. The dianion B 3 ( BO ) 3 2 - possesses a perfect triangular D3h form, that undergoes to lower symmetry in the anionic (C2v) and neutral (Cs) states. The adiabatic electron affinity of B6O3 and vertical detachment energy of B 6 O 3 - amount to 3.97 and 4.07 eV, respectively. NBO and ELF analyses reveal that B 6 O 3 2 - possesses a global π-aromaticity, a local σ-electron delocalization, and a three-center-two-electron bond. The high stability of the dianion illustrates the growth mechanism of boron oxide clusters that is governed by formation of strong BO bonds and small boron cycles.