The structure and potential energy function of B2C(1A1) and BC2(2A')

Quadratic configuration interaction method including single and duble substitutions has been used to optimize the possible ground-state structures of B2C and BC2 molecules with the 6-311 ++ G(d, f) and 6-311G(df, pd) basis set. The results show that the ground state of B2C molecule is of C-2v symmetry and of (1)A(1) state, the ground state of BC2 molecule is of C-s symmetry and of (2)A ' state. And the equilibrium geometry, dissociation energy, harmonic frequency and force constant have been calculated. The potential energy functions of B2C and BC2 have been derived from the many-body expansion theory. The potential energy functions describe correctly the configurations and the dissociation energies of the two ground-state molecules. Molecular reaction kinetics of B + BC -> B2C and B + CC -> BC2 based on the potential energy functions is discussed briefly.