Theoretical investigation on structure and stability of some neutral
rare gas molecules F-Rg-BR2 (R = F, OH, CN, CCH)
Abstract
Ab initio and DFT calculations were performed to investigate the
structure, stability, and nature of chemical bonding of the
F-Rg-BR2 (R = F, OH, CN and CCH; Rg = Ar, Kr, Xe and Rn)
molecules. The geometries are optimized for ground as well as transition
states using the B3LYP-D3 and MP2 methods. It has been found that the
F-Rg-B portion of F-Rg-BR2 species is linear in the
ground state but curved in the transition state. The NBO, AIM, ELF and
EDA analyses suggest that the molecules can be expressed as
F-(Rg-BR2)+ due to
the covalent Rg-B bond and the ionic interaction between F and Rg.
Calculations assert the metastable behavior of the
F-Rg-BR2 molecules, thermodynamic data shows that
F-Rg-BR2 can spontaneously dissociates into
BFR2 + Rg, the considerable energy barrier of this
two-body dissociation channel calculated by the B3LYP-D3, MP2 and
CCSD(T) methods affirms the kinetic stability of the
F-Rg-BR2 molecules. Thus F-Rg-BR2
molecules are kinetically protected against the decomposition reaction
and may be identified under cryogenic conditions in solid rare gas
matrices or in the gas phase.