Novel Rare Gas Ions BXe+, BKr+, and BAr+ Formed in a Halogen/Rare Gas Exchange Reaction

Abstract

Singly charged rare gas borynium ions were prepared for the first time by making use of mass-selected ion/molecule reactions in a triple-quadrupole mass spectrometer. Halogen for rare-gas exchange reactions leading to the formation of the novel species BAr+, BKr+, and BXe+ were carried out by allowing the radical cation BBr+• to react with neutral rare gas atoms in the second quadrupole under conditions typically used for collision-induced dissociation (CID) in tandem mass spectrometry experiments. The ions formed contain the bonds B−Ar, B−Kr, and B−Xe, the lengths of which were calculated at the B3-LYP/LANL2DZ level of theory to be 2.590, 2.635, and 2.713 A, respectively. Natural bond orbital (NBO) population analysis revealed that the bond order increases with increasing size of the rare gas atom: Ar < Kr < Xe. The reactions leading to the formation of the singly charged boron cations of Ar, Kr, and Xe are endothermic by 50.1, 45.8, and 38.7 kcal/mol, respectively. The energy required to drive these re...