Investigation of BN orientation effect and its number at spoke position of sumanene nanobowl on its properties

 In this study, the C=C bonds at spoke position of sumanene nanobowl have been replaced with B-N units in two different orientation patterns. The computational studies have been investigated employing the density functional theory (DFT). The effect of orientation of BN units and also the number of them have studied on nonlinear optical (NLO) properties of sumanene. The doped structures show the significant changes in geometric structure, aromaticity and the first static hyperpolarizability (β0) values. In BN-orientation, with increasing number of BN units, bowl depth and dipole moment decrease linearly and reach to 0.0 Å and 0.0 D for 6BN structure. In another orientation (NB), bowl depth and dipole moment increase and reach to maximum values (1.808 Å and 5.0 D) in 6NB structure. It is found that the energy gap (Egap) is narrowed in BN/CC isosterism relative to the pristine sumanene. Also, the decrease of average NICS (Nucleus independent chemical shift) values indicate that aromaticity of BN-sumanene structures has decreased compared to the sumanene nanobowl. The NLO properties of all structures has increased in both directions, so that the value of β0 in the 2BN-3 structure is 953.1 au, which is 12 times that of the sumanene. The results of this research can be useful in designing new NLO materials.