Structure and stability of (HBNH)n clusters

Structures and thermodynamic properties of the imidoboranes (HBNH)(n) (n = 1-16) have been investigated theoretically at the B3LYP/6-31G* level of theory. Needle-shaped oligomers that violate the isolated square rule were found to be more stable than cage isomers. The needle-shaped oligomer with n = 16 was predicted to be exceptionally stable at low temperature, hexamer and octamer clusters dominated the gas phase at higher temperature. The highest oligornerization degree of the spontaneous cluster formation has been estimated. It was concluded that generation of the gas phase (HBNH)(n) clusters with oligomerization degree n >= 24 was viable, making these species possible intermediates involved in the gas phase generation of BN nanoparticles.