Structure, Nature of Bonding, and Charge Distribution in Hydridoborane Dications BH n 2+ (n = 1−8)1a

Structures and stabilities of hydridoborane dications BH n 2+ (n = 1−8; 1 − 8a) were calculated at the ab initio MP2/aug-cc-pVTZ and DFT B3LYP/aug-cc-pVTZ levels of theory. The dications BH2+ (1a) and BH2 2+ (2a) were characterized as being unstable, both kinetically and thermodynamically. However, dications BH n 2+ (n = 3−8; 3 − 8a) have a considerable kinetic barrier for deprotonation. Each of the structures 3 − 8a contains one or more two-electron, three-center (2e−3c) bonds. In the BH n 2+ (n = 1−8) series, the calculated energies and kinetic barriers of protodissociation indicate an increasing stability of the dications toward protodissociation with the increase in the number of hydrogen substituents.